Revisit layout of struct mptcp_subflow_context #24

cpaasch · 2020-05-13T17:59:40Z

From Paolo:

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index e4ca6320ce76..f5adca93e8fb 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -290,6 +290,7 @@ struct mptcp_subflow_context {
            data_avail : 1,
            rx_eof : 1,
            data_fin_tx_enable : 1,
+           use_64bit_ack : 1, /* Set when we received a 64-bit DSN */
            can_ack : 1;        /* only after processing the remote a key */
    u64     data_fin_tx_seq;
    u32     remote_nonce;

Possibly with a wider scope than this patch, but the above bitfields
contains both fields that are rarely changed (data_fin_tx_enable,
can_ack, request_mptcp, etc...) and fields that are set on every packet
/every DSS (map_vaild, data_avail, the newly added use_64bit_ack).

At least 'data_avail' is accessed without holding the ssk socket lock
by mptcp_subflow_recv_lookup(). Perhaps we could revisit the binary
layout of this struct?

…em boot up Booting one of my machines, it triggered the following crash: Kernel/User page tables isolation: enabled ftrace: allocating 36577 entries in 143 pages Starting tracer 'function' BUG: unable to handle page fault for address: ffffffffa000005c #PF: supervisor write access in kernel mode #PF: error_code(0x0003) - permissions violation PGD 2014067 P4D 2014067 PUD 2015063 PMD 7b253067 PTE 7b252061 Oops: 0003 [#1] PREEMPT SMP PTI CPU: 0 PID: 0 Comm: swapper Not tainted 5.4.0-test+ #24 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007 RIP: 0010:text_poke_early+0x4a/0x58 Code: 34 24 48 89 54 24 08 e8 bf 72 0b 00 48 8b 34 24 48 8b 4c 24 08 84 c0 74 0b 48 89 df f3 a4 48 83 c4 10 5b c3 9c 58 fa 48 89 df <f3> a4 50 9d 48 83 c4 10 5b e9 d6 f9 ff ff 0 41 57 49 RSP: 0000:ffffffff82003d38 EFLAGS: 00010046 RAX: 0000000000000046 RBX: ffffffffa000005c RCX: 0000000000000005 RDX: 0000000000000005 RSI: ffffffff825b9a90 RDI: ffffffffa000005c RBP: ffffffffa000005c R08: 0000000000000000 R09: ffffffff8206e6e0 R10: ffff88807b01f4c0 R11: ffffffff8176c106 R12: ffffffff8206e6e0 R13: ffffffff824f2440 R14: 0000000000000000 R15: ffffffff8206eac0 FS: 0000000000000000(0000) GS:ffff88807d400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffa000005c CR3: 0000000002012000 CR4: 00000000000006b0 Call Trace: text_poke_bp+0x27/0x64 ? mutex_lock+0x36/0x5d arch_ftrace_update_trampoline+0x287/0x2d5 ? ftrace_replace_code+0x14b/0x160 ? ftrace_update_ftrace_func+0x65/0x6c __register_ftrace_function+0x6d/0x81 ftrace_startup+0x23/0xc1 register_ftrace_function+0x20/0x37 func_set_flag+0x59/0x77 __set_tracer_option.isra.19+0x20/0x3e trace_set_options+0xd6/0x13e apply_trace_boot_options+0x44/0x6d register_tracer+0x19e/0x1ac early_trace_init+0x21b/0x2c9 start_kernel+0x241/0x518 ? load_ucode_intel_bsp+0x21/0x52 secondary_startup_64+0xa4/0xb0 I was able to trigger it on other machines, when I added to the kernel command line of both "ftrace=function" and "trace_options=func_stack_trace". The cause is the "ftrace=function" would register the function tracer and create a trampoline, and it will set it as executable and read-only. Then the "trace_options=func_stack_trace" would then update the same trampoline to include the stack tracer version of the function tracer. But since the trampoline already exists, it updates it with text_poke_bp(). The problem is that text_poke_bp() called while system_state == SYSTEM_BOOTING, it will simply do a memcpy() and not the page mapping, as it would think that the text is still read-write. But in this case it is not, and we take a fault and crash. Instead, lets keep the ftrace trampolines read-write during boot up, and then when the kernel executable text is set to read-only, the ftrace trampolines get set to read-only as well. Link: https://lkml.kernel.org/r/[email protected] Cc: Ingo Molnar <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: [email protected] Fixes: 768ae44 ("x86/ftrace: Use text_poke()") Acked-by: Peter Zijlstra <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>

I compiled with AddressSanitizer and I had these memory leaks while I was using the tep_parse_format function: Direct leak of 28 byte(s) in 4 object(s) allocated from: #0 0x7fb07db49ffe in __interceptor_realloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dffe) #1 0x7fb07a724228 in extend_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:985 #2 0x7fb07a724c21 in __read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1140 #3 0x7fb07a724f78 in read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1206 #4 0x7fb07a725191 in __read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1291 #5 0x7fb07a7251df in read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1299 #6 0x7fb07a72e6c8 in process_dynamic_array_len /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:2849 #7 0x7fb07a7304b8 in process_function /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3161 #8 0x7fb07a730900 in process_arg_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3207 #9 0x7fb07a727c0b in process_arg /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1786 #10 0x7fb07a731080 in event_read_print_args /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3285 #11 0x7fb07a731722 in event_read_print /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3369 #12 0x7fb07a740054 in __tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6335 #13 0x7fb07a74047a in __parse_event /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6389 #14 0x7fb07a740536 in tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6431 #15 0x7fb07a785acf in parse_event ../../../src/fs-src/fs.c:251 #16 0x7fb07a785ccd in parse_systems ../../../src/fs-src/fs.c:284 #17 0x7fb07a786fb3 in read_metadata ../../../src/fs-src/fs.c:593 #18 0x7fb07a78760e in ftrace_fs_source_init ../../../src/fs-src/fs.c:727 #19 0x7fb07d90c19c in add_component_with_init_method_data ../../../../src/lib/graph/graph.c:1048 #20 0x7fb07d90c87b in add_source_component_with_initialize_method_data ../../../../src/lib/graph/graph.c:1127 #21 0x7fb07d90c92a in bt_graph_add_source_component ../../../../src/lib/graph/graph.c:1152 #22 0x55db11aa632e in cmd_run_ctx_create_components_from_config_components ../../../src/cli/babeltrace2.c:2252 #23 0x55db11aa6fda in cmd_run_ctx_create_components ../../../src/cli/babeltrace2.c:2347 #24 0x55db11aa780c in cmd_run ../../../src/cli/babeltrace2.c:2461 #25 0x55db11aa8a7d in main ../../../src/cli/babeltrace2.c:2673 #26 0x7fb07d5460b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2) The token variable in the process_dynamic_array_len function is allocated in the read_expect_type function, but is not freed before calling the read_token function. Free the token variable before calling read_token in order to plug the leak. Signed-off-by: Philippe Duplessis-Guindon <[email protected]> Reviewed-by: Steven Rostedt (VMware) <[email protected]> Link: https://lore.kernel.org/linux-trace-devel/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

For early sections, its memmap is handled specially even sub-section is enabled. The memmap could only be populated as a whole. Quoted from the comment of section_activate(): * The early init code does not consider partially populated * initial sections, it simply assumes that memory will never be * referenced. If we hot-add memory into such a section then we * do not need to populate the memmap and can simply reuse what * is already there. While current section_deactivate() breaks this rule. When hot-remove a sub-section, section_deactivate() would depopulate its memmap. The consequence is if we hot-add this subsection again, its memmap never get proper populated. We can reproduce the case by following steps: 1. Hacking qemu to allow sub-section early section : diff --git a/hw/i386/pc.c b/hw/i386/pc.c : index 51b3050d01..c6a78d83c0 100644 : --- a/hw/i386/pc.c : +++ b/hw/i386/pc.c : @@ -1010,7 +1010,7 @@ void pc_memory_init(PCMachineState *pcms, : } : : machine->device_memory->base = : - ROUND_UP(0x100000000ULL + x86ms->above_4g_mem_size, 1 * GiB); : + 0x100000000ULL + x86ms->above_4g_mem_size; : : if (pcmc->enforce_aligned_dimm) { : /* size device region assuming 1G page max alignment per slot */ 2. Bootup qemu with PSE disabled and a sub-section aligned memory size Part of the qemu command would look like this: sudo x86_64-softmmu/qemu-system-x86_64 \ --enable-kvm -cpu host,pse=off \ -m 4160M,maxmem=20G,slots=1 \ -smp sockets=2,cores=16 \ -numa node,nodeid=0,cpus=0-1 -numa node,nodeid=1,cpus=2-3 \ -machine pc,nvdimm \ -nographic \ -object memory-backend-ram,id=mem0,size=8G \ -device nvdimm,id=vm0,memdev=mem0,node=0,addr=0x144000000,label-size=128k 3. Re-config a pmem device with sub-section size in guest ndctl create-namespace --force --reconfig=namespace0.0 --mode=devdax --size=16M Then you would see the following call trace: pmem0: detected capacity change from 0 to 16777216 BUG: unable to handle page fault for address: ffffec73c51000b4 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 81ff8067 P4D 81ff8067 PUD 81ff7067 PMD 1437cb067 PTE 0 Oops: 0002 [#1] SMP NOPTI CPU: 16 PID: 1348 Comm: ndctl Kdump: loaded Tainted: G W 5.8.0-rc2+ #24 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.4 RIP: 0010:memmap_init_zone+0x154/0x1c2 Code: 77 16 f6 40 10 02 74 10 48 03 48 08 48 89 cb 48 c1 eb 0c e9 3a ff ff ff 48 89 df 48 c1 e7 06 48f RSP: 0018:ffffbdc7011a39b0 EFLAGS: 00010282 RAX: ffffec73c5100088 RBX: 0000000000144002 RCX: 0000000000144000 RDX: 0000000000000004 RSI: 007ffe0000000000 RDI: ffffec73c5100080 RBP: 027ffe0000000000 R08: 0000000000000001 R09: ffff9f8d38f6d708 R10: ffffec73c0000000 R11: 0000000000000000 R12: 0000000000000004 R13: 0000000000000001 R14: 0000000000144200 R15: 0000000000000000 FS: 00007efe6b65d780(0000) GS:ffff9f8d3f780000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffec73c51000b4 CR3: 000000007d718000 CR4: 0000000000340ee0 Call Trace: move_pfn_range_to_zone+0x128/0x150 memremap_pages+0x4e4/0x5a0 devm_memremap_pages+0x1e/0x60 dev_dax_probe+0x69/0x160 [device_dax] really_probe+0x298/0x3c0 driver_probe_device+0xe1/0x150 ? driver_allows_async_probing+0x50/0x50 bus_for_each_drv+0x7e/0xc0 __device_attach+0xdf/0x160 bus_probe_device+0x8e/0xa0 device_add+0x3b9/0x740 __devm_create_dev_dax+0x127/0x1c0 __dax_pmem_probe+0x1f2/0x219 [dax_pmem_core] dax_pmem_probe+0xc/0x1b [dax_pmem] nvdimm_bus_probe+0x69/0x1c0 [libnvdimm] really_probe+0x147/0x3c0 driver_probe_device+0xe1/0x150 device_driver_attach+0x53/0x60 bind_store+0xd1/0x110 kernfs_fop_write+0xce/0x1b0 vfs_write+0xb6/0x1a0 ksys_write+0x5f/0xe0 do_syscall_64+0x4d/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: ba72b4c ("mm/sparsemem: support sub-section hotplug") Signed-off-by: Wei Yang <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Acked-by: David Hildenbrand <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Dan Williams <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>

This fix is for a failure that occurred in the DWARF unwind perf test. Stack unwinders may probe memory when looking for frames. Memory sanitizer will poison and track uninitialized memory on the stack, and on the heap if the value is copied to the heap. This can lead to false memory sanitizer failures for the use of an uninitialized value. Avoid this problem by removing the poison on the copied stack. The full msan failure with track origins looks like: ==2168==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x559ceb10755b in handle_cfi elfutils/libdwfl/frame_unwind.c:648:8 #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #23 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceb106acf in __libdwfl_frame_reg_set elfutils/libdwfl/frame_unwind.c:77:22 #1 0x559ceb106acf in handle_cfi elfutils/libdwfl/frame_unwind.c:627:13 #2 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #3 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #4 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #5 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #6 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #7 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #8 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #9 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #10 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #11 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #12 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #13 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #14 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #15 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #16 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #17 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #18 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #19 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #20 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #21 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #22 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #23 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #24 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceb106a54 in handle_cfi elfutils/libdwfl/frame_unwind.c:613:9 #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #23 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceaff8800 in memory_read tools/perf/util/unwind-libdw.c:156:10 #1 0x559ceb10f053 in expr_eval elfutils/libdwfl/frame_unwind.c:501:13 #2 0x559ceb1060cc in handle_cfi elfutils/libdwfl/frame_unwind.c:603:18 #3 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #4 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #5 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #6 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #7 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #8 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #9 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #10 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #11 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #12 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #13 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #14 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #15 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #16 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #17 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #18 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #19 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #20 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #21 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #22 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #23 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #24 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #25 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559cea9027d9 in __msan_memcpy llvm/llvm-project/compiler-rt/lib/msan/msan_interceptors.cpp:1558:3 #1 0x559cea9d2185 in sample_ustack tools/perf/arch/x86/tests/dwarf-unwind.c:41:2 #2 0x559cea9d202c in test__arch_unwind_sample tools/perf/arch/x86/tests/dwarf-unwind.c:72:9 #3 0x559ceabc9cbd in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:106:6 #4 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #5 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #6 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #7 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #8 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #9 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #10 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #11 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #12 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #13 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #14 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #15 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #16 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #17 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was created by an allocation of 'bf' in the stack frame of function 'perf_event__synthesize_mmap_events' #0 0x559ceafc5f60 in perf_event__synthesize_mmap_events tools/perf/util/synthetic-events.c:445 SUMMARY: MemorySanitizer: use-of-uninitialized-value elfutils/libdwfl/frame_unwind.c:648:8 in handle_cfi Signed-off-by: Ian Rogers <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: [email protected] Cc: Jiri Olsa <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Sandeep Dasgupta <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

This patch cleared use_ack and use_map when dropping other suboptions to fix the following syzkaller BUG: [ 15.223006] BUG: unable to handle page fault for address: 0000000000223b10 [ 15.223700] #PF: supervisor read access in kernel mode [ 15.224209] #PF: error_code(0x0000) - not-present page [ 15.224724] PGD b8d5067 P4D b8d5067 PUD c0a5067 PMD 0 [ 15.225237] Oops: 0000 [#1] SMP [ 15.225556] CPU: 0 PID: 7747 Comm: syz-executor Not tainted 5.10.0-rc6+ #24 [ 15.226281] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 15.227292] RIP: 0010:skb_release_data+0x89/0x1e0 [ 15.227816] Code: 5b 5d 41 5c 41 5d 41 5e 41 5f e9 02 06 8a ff e8 fd 05 8a ff 45 31 ed 80 7d 02 00 4c 8d 65 30 74 55 e8 eb 05 8a ff 49 8b 1c 24 <4c> 8b 7b 08 41 f6 c7 01 0f 85 18 01 00 00 e8 d4 05 8a ff 8b 43 34 [ 15.229669] RSP: 0018:ffffc900019c7c08 EFLAGS: 00010293 [ 15.230188] RAX: ffff88800daad900 RBX: 0000000000223b08 RCX: 0000000000000006 [ 15.230895] RDX: 0000000000000000 RSI: ffffffff818e06c5 RDI: ffff88807f6dc700 [ 15.231593] RBP: ffff88807f71a4c0 R08: 0000000000000001 R09: 0000000000000001 [ 15.232299] R10: ffffc900019c7c18 R11: 0000000000000000 R12: ffff88807f71a4f0 [ 15.233007] R13: 0000000000000000 R14: ffff88807f6dc700 R15: 0000000000000002 [ 15.233714] FS: 00007f65d9b5f700(0000) GS:ffff88807c400000(0000) knlGS:0000000000000000 [ 15.234509] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.235081] CR2: 0000000000223b10 CR3: 000000000b883000 CR4: 00000000000006f0 [ 15.235788] Call Trace: [ 15.236042] skb_release_all+0x28/0x30 [ 15.236419] __kfree_skb+0x11/0x20 [ 15.236768] tcp_data_queue+0x270/0x1240 [ 15.237161] ? tcp_urg+0x50/0x2a0 [ 15.237496] tcp_rcv_established+0x39a/0x890 [ 15.237997] ? mark_held_locks+0x49/0x70 [ 15.238467] tcp_v4_do_rcv+0xb9/0x270 [ 15.238915] __release_sock+0x8a/0x160 [ 15.239365] release_sock+0x32/0xd0 [ 15.239793] __inet_stream_connect+0x1d2/0x400 [ 15.240313] ? do_wait_intr_irq+0x80/0x80 [ 15.240791] inet_stream_connect+0x36/0x50 [ 15.241275] mptcp_stream_connect+0x69/0x1b0 [ 15.241787] __sys_connect+0x122/0x140 [ 15.242236] ? syscall_enter_from_user_mode+0x17/0x50 [ 15.242836] ? lockdep_hardirqs_on_prepare+0xd4/0x170 [ 15.243436] __x64_sys_connect+0x1a/0x20 [ 15.243924] do_syscall_64+0x33/0x40 [ 15.244313] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 15.244821] RIP: 0033:0x7f65d946e469 [ 15.245183] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ff 49 2b 00 f7 d8 64 89 01 48 [ 15.247019] RSP: 002b:00007f65d9b5eda8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a [ 15.247770] RAX: ffffffffffffffda RBX: 000000000049bf00 RCX: 00007f65d946e469 [ 15.248471] RDX: 0000000000000010 RSI: 00000000200000c0 RDI: 0000000000000005 [ 15.249205] RBP: 000000000049bf00 R08: 0000000000000000 R09: 0000000000000000 [ 15.249908] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000049bf0c [ 15.250603] R13: 00007fffe8a25cef R14: 00007f65d9b3f000 R15: 0000000000000003 [ 15.251312] Modules linked in: [ 15.251626] CR2: 0000000000223b10 [ 15.251965] BUG: kernel NULL pointer dereference, address: 0000000000000048 [ 15.252005] ---[ end trace f5c51fe19123c773 ]--- [ 15.252822] #PF: supervisor read access in kernel mode [ 15.252823] #PF: error_code(0x0000) - not-present page [ 15.252825] PGD c6c6067 P4D c6c6067 PUD c0d8067 [ 15.253294] RIP: 0010:skb_release_data+0x89/0x1e0 [ 15.253910] PMD 0 [ 15.253914] Oops: 0000 [#2] SMP [ 15.253917] CPU: 1 PID: 7746 Comm: syz-executor Tainted: G D 5.10.0-rc6+ #24 [ 15.253920] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 15.254435] Code: 5b 5d 41 5c 41 5d 41 5e 41 5f e9 02 06 8a ff e8 fd 05 8a ff 45 31 ed 80 7d 02 00 4c 8d 65 30 74 55 e8 eb 05 8a ff 49 8b 1c 24 <4c> 8b 7b 08 41 f6 c7 01 0f 85 18 01 00 00 e8 d4 05 8a ff 8b 43 34 [ 15.254899] RIP: 0010:skb_release_data+0x89/0x1e0 [ 15.254902] Code: 5b 5d 41 5c 41 5d 41 5e 41 5f e9 02 06 8a ff e8 fd 05 8a ff 45 31 ed 80 7d 02 00 4c 8d 65 30 74 55 e8 eb 05 8a ff 49 8b 1c 24 <4c> 8b 7b 08 41 f6 c7 01 0f 85 18 01 00 00 e8 d4 05 8a ff 8b 43 34 [ 15.254905] RSP: 0018:ffffc900019bfc08 EFLAGS: 00010293 [ 15.255376] RSP: 0018:ffffc900019c7c08 EFLAGS: 00010293 [ 15.255580] [ 15.255583] RAX: ffff888004a7ac80 RBX: 0000000000000040 RCX: 0000000000000000 [ 15.255912] [ 15.256724] RDX: 0000000000000000 RSI: ffffffff818e06c5 RDI: ffff88807f6ddd00 [ 15.257620] RAX: ffff88800daad900 RBX: 0000000000223b08 RCX: 0000000000000006 [ 15.259817] RBP: ffff88800e9006c0 R08: 0000000000000000 R09: 0000000000000000 [ 15.259818] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88800e9006f0 [ 15.259820] R13: 0000000000000000 R14: ffff88807f6ddd00 R15: 0000000000000002 [ 15.259822] FS: 00007fae4a60a700(0000) GS:ffff88807c500000(0000) knlGS:0000000000000000 [ 15.259826] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.260296] RDX: 0000000000000000 RSI: ffffffff818e06c5 RDI: ffff88807f6dc700 [ 15.262514] CR2: 0000000000000048 CR3: 000000000b89c000 CR4: 00000000000006e0 [ 15.262515] Call Trace: [ 15.262519] skb_release_all+0x28/0x30 [ 15.262523] __kfree_skb+0x11/0x20 [ 15.263054] RBP: ffff88807f71a4c0 R08: 0000000000000001 R09: 0000000000000001 [ 15.263680] tcp_data_queue+0x270/0x1240 [ 15.263843] R10: ffffc900019c7c18 R11: 0000000000000000 R12: ffff88807f71a4f0 [ 15.264693] ? tcp_urg+0x50/0x2a0 [ 15.264856] R13: 0000000000000000 R14: ffff88807f6dc700 R15: 0000000000000002 [ 15.265720] tcp_rcv_established+0x39a/0x890 [ 15.266438] FS: 00007f65d9b5f700(0000) GS:ffff88807c400000(0000) knlGS:0000000000000000 [ 15.267283] ? __schedule+0x3fa/0x880 [ 15.267287] tcp_v4_do_rcv+0xb9/0x270 [ 15.267290] __release_sock+0x8a/0x160 [ 15.268049] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.268788] release_sock+0x32/0xd0 [ 15.268791] __inet_stream_connect+0x1d2/0x400 [ 15.268795] ? do_wait_intr_irq+0x80/0x80 [ 15.269593] CR2: 0000000000223b10 CR3: 000000000b883000 CR4: 00000000000006f0 [ 15.270246] inet_stream_connect+0x36/0x50 [ 15.270250] mptcp_stream_connect+0x69/0x1b0 [ 15.270253] __sys_connect+0x122/0x140 [ 15.271097] Kernel panic - not syncing: Fatal exception [ 15.271820] ? syscall_enter_from_user_mode+0x17/0x50 [ 15.283542] ? lockdep_hardirqs_on_prepare+0xd4/0x170 [ 15.284275] __x64_sys_connect+0x1a/0x20 [ 15.284853] do_syscall_64+0x33/0x40 [ 15.285369] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 15.286105] RIP: 0033:0x7fae49f19469 [ 15.286638] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ff 49 2b 00 f7 d8 64 89 01 48 [ 15.289295] RSP: 002b:00007fae4a609da8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a [ 15.290375] RAX: ffffffffffffffda RBX: 000000000049bf00 RCX: 00007fae49f19469 [ 15.291403] RDX: 0000000000000010 RSI: 00000000200000c0 RDI: 0000000000000005 [ 15.292437] RBP: 000000000049bf00 R08: 0000000000000000 R09: 0000000000000000 [ 15.293456] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000049bf0c [ 15.294473] R13: 00007fff0004b6bf R14: 00007fae4a5ea000 R15: 0000000000000003 [ 15.295492] Modules linked in: [ 15.295944] CR2: 0000000000000048 [ 15.296567] Kernel Offset: disabled [ 15.296941] ---[ end Kernel panic - not syncing: Fatal exception ]--- Reported-by: Christoph Paasch <[email protected]> Closes: #104 Fixes: 84dfe36 (mptcp: send out dedicated ADD_ADDR packet) Acked-by: Paolo Abeni <[email protected]> Signed-off-by: Geliang Tang <[email protected]>

This patch cleared use_ack and use_map when dropping other suboptions to fix the following syzkaller BUG: [ 15.223006] BUG: unable to handle page fault for address: 0000000000223b10 [ 15.223700] #PF: supervisor read access in kernel mode [ 15.224209] #PF: error_code(0x0000) - not-present page [ 15.224724] PGD b8d5067 P4D b8d5067 PUD c0a5067 PMD 0 [ 15.225237] Oops: 0000 [#1] SMP [ 15.225556] CPU: 0 PID: 7747 Comm: syz-executor Not tainted 5.10.0-rc6+ #24 [ 15.226281] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 15.227292] RIP: 0010:skb_release_data+0x89/0x1e0 [ 15.227816] Code: 5b 5d 41 5c 41 5d 41 5e 41 5f e9 02 06 8a ff e8 fd 05 8a ff 45 31 ed 80 7d 02 00 4c 8d 65 30 74 55 e8 eb 05 8a ff 49 8b 1c 24 <4c> 8b 7b 08 41 f6 c7 01 0f 85 18 01 00 00 e8 d4 05 8a ff 8b 43 34 [ 15.229669] RSP: 0018:ffffc900019c7c08 EFLAGS: 00010293 [ 15.230188] RAX: ffff88800daad900 RBX: 0000000000223b08 RCX: 0000000000000006 [ 15.230895] RDX: 0000000000000000 RSI: ffffffff818e06c5 RDI: ffff88807f6dc700 [ 15.231593] RBP: ffff88807f71a4c0 R08: 0000000000000001 R09: 0000000000000001 [ 15.232299] R10: ffffc900019c7c18 R11: 0000000000000000 R12: ffff88807f71a4f0 [ 15.233007] R13: 0000000000000000 R14: ffff88807f6dc700 R15: 0000000000000002 [ 15.233714] FS: 00007f65d9b5f700(0000) GS:ffff88807c400000(0000) knlGS:0000000000000000 [ 15.234509] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.235081] CR2: 0000000000223b10 CR3: 000000000b883000 CR4: 00000000000006f0 [ 15.235788] Call Trace: [ 15.236042] skb_release_all+0x28/0x30 [ 15.236419] __kfree_skb+0x11/0x20 [ 15.236768] tcp_data_queue+0x270/0x1240 [ 15.237161] ? tcp_urg+0x50/0x2a0 [ 15.237496] tcp_rcv_established+0x39a/0x890 [ 15.237997] ? mark_held_locks+0x49/0x70 [ 15.238467] tcp_v4_do_rcv+0xb9/0x270 [ 15.238915] __release_sock+0x8a/0x160 [ 15.239365] release_sock+0x32/0xd0 [ 15.239793] __inet_stream_connect+0x1d2/0x400 [ 15.240313] ? do_wait_intr_irq+0x80/0x80 [ 15.240791] inet_stream_connect+0x36/0x50 [ 15.241275] mptcp_stream_connect+0x69/0x1b0 [ 15.241787] __sys_connect+0x122/0x140 [ 15.242236] ? syscall_enter_from_user_mode+0x17/0x50 [ 15.242836] ? lockdep_hardirqs_on_prepare+0xd4/0x170 [ 15.243436] __x64_sys_connect+0x1a/0x20 [ 15.243924] do_syscall_64+0x33/0x40 [ 15.244313] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 15.244821] RIP: 0033:0x7f65d946e469 [ 15.245183] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ff 49 2b 00 f7 d8 64 89 01 48 [ 15.247019] RSP: 002b:00007f65d9b5eda8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a [ 15.247770] RAX: ffffffffffffffda RBX: 000000000049bf00 RCX: 00007f65d946e469 [ 15.248471] RDX: 0000000000000010 RSI: 00000000200000c0 RDI: 0000000000000005 [ 15.249205] RBP: 000000000049bf00 R08: 0000000000000000 R09: 0000000000000000 [ 15.249908] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000049bf0c [ 15.250603] R13: 00007fffe8a25cef R14: 00007f65d9b3f000 R15: 0000000000000003 [ 15.251312] Modules linked in: [ 15.251626] CR2: 0000000000223b10 [ 15.251965] BUG: kernel NULL pointer dereference, address: 0000000000000048 [ 15.252005] ---[ end trace f5c51fe19123c773 ]--- [ 15.252822] #PF: supervisor read access in kernel mode [ 15.252823] #PF: error_code(0x0000) - not-present page [ 15.252825] PGD c6c6067 P4D c6c6067 PUD c0d8067 [ 15.253294] RIP: 0010:skb_release_data+0x89/0x1e0 [ 15.253910] PMD 0 [ 15.253914] Oops: 0000 [#2] SMP [ 15.253917] CPU: 1 PID: 7746 Comm: syz-executor Tainted: G D 5.10.0-rc6+ #24 [ 15.253920] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 15.254435] Code: 5b 5d 41 5c 41 5d 41 5e 41 5f e9 02 06 8a ff e8 fd 05 8a ff 45 31 ed 80 7d 02 00 4c 8d 65 30 74 55 e8 eb 05 8a ff 49 8b 1c 24 <4c> 8b 7b 08 41 f6 c7 01 0f 85 18 01 00 00 e8 d4 05 8a ff 8b 43 34 [ 15.254899] RIP: 0010:skb_release_data+0x89/0x1e0 [ 15.254902] Code: 5b 5d 41 5c 41 5d 41 5e 41 5f e9 02 06 8a ff e8 fd 05 8a ff 45 31 ed 80 7d 02 00 4c 8d 65 30 74 55 e8 eb 05 8a ff 49 8b 1c 24 <4c> 8b 7b 08 41 f6 c7 01 0f 85 18 01 00 00 e8 d4 05 8a ff 8b 43 34 [ 15.254905] RSP: 0018:ffffc900019bfc08 EFLAGS: 00010293 [ 15.255376] RSP: 0018:ffffc900019c7c08 EFLAGS: 00010293 [ 15.255580] [ 15.255583] RAX: ffff888004a7ac80 RBX: 0000000000000040 RCX: 0000000000000000 [ 15.255912] [ 15.256724] RDX: 0000000000000000 RSI: ffffffff818e06c5 RDI: ffff88807f6ddd00 [ 15.257620] RAX: ffff88800daad900 RBX: 0000000000223b08 RCX: 0000000000000006 [ 15.259817] RBP: ffff88800e9006c0 R08: 0000000000000000 R09: 0000000000000000 [ 15.259818] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88800e9006f0 [ 15.259820] R13: 0000000000000000 R14: ffff88807f6ddd00 R15: 0000000000000002 [ 15.259822] FS: 00007fae4a60a700(0000) GS:ffff88807c500000(0000) knlGS:0000000000000000 [ 15.259826] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.260296] RDX: 0000000000000000 RSI: ffffffff818e06c5 RDI: ffff88807f6dc700 [ 15.262514] CR2: 0000000000000048 CR3: 000000000b89c000 CR4: 00000000000006e0 [ 15.262515] Call Trace: [ 15.262519] skb_release_all+0x28/0x30 [ 15.262523] __kfree_skb+0x11/0x20 [ 15.263054] RBP: ffff88807f71a4c0 R08: 0000000000000001 R09: 0000000000000001 [ 15.263680] tcp_data_queue+0x270/0x1240 [ 15.263843] R10: ffffc900019c7c18 R11: 0000000000000000 R12: ffff88807f71a4f0 [ 15.264693] ? tcp_urg+0x50/0x2a0 [ 15.264856] R13: 0000000000000000 R14: ffff88807f6dc700 R15: 0000000000000002 [ 15.265720] tcp_rcv_established+0x39a/0x890 [ 15.266438] FS: 00007f65d9b5f700(0000) GS:ffff88807c400000(0000) knlGS:0000000000000000 [ 15.267283] ? __schedule+0x3fa/0x880 [ 15.267287] tcp_v4_do_rcv+0xb9/0x270 [ 15.267290] __release_sock+0x8a/0x160 [ 15.268049] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.268788] release_sock+0x32/0xd0 [ 15.268791] __inet_stream_connect+0x1d2/0x400 [ 15.268795] ? do_wait_intr_irq+0x80/0x80 [ 15.269593] CR2: 0000000000223b10 CR3: 000000000b883000 CR4: 00000000000006f0 [ 15.270246] inet_stream_connect+0x36/0x50 [ 15.270250] mptcp_stream_connect+0x69/0x1b0 [ 15.270253] __sys_connect+0x122/0x140 [ 15.271097] Kernel panic - not syncing: Fatal exception [ 15.271820] ? syscall_enter_from_user_mode+0x17/0x50 [ 15.283542] ? lockdep_hardirqs_on_prepare+0xd4/0x170 [ 15.284275] __x64_sys_connect+0x1a/0x20 [ 15.284853] do_syscall_64+0x33/0x40 [ 15.285369] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 15.286105] RIP: 0033:0x7fae49f19469 [ 15.286638] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ff 49 2b 00 f7 d8 64 89 01 48 [ 15.289295] RSP: 002b:00007fae4a609da8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a [ 15.290375] RAX: ffffffffffffffda RBX: 000000000049bf00 RCX: 00007fae49f19469 [ 15.291403] RDX: 0000000000000010 RSI: 00000000200000c0 RDI: 0000000000000005 [ 15.292437] RBP: 000000000049bf00 R08: 0000000000000000 R09: 0000000000000000 [ 15.293456] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000049bf0c [ 15.294473] R13: 00007fff0004b6bf R14: 00007fae4a5ea000 R15: 0000000000000003 [ 15.295492] Modules linked in: [ 15.295944] CR2: 0000000000000048 [ 15.296567] Kernel Offset: disabled [ 15.296941] ---[ end Kernel panic - not syncing: Fatal exception ]--- Reported-by: Christoph Paasch <[email protected]> Fixes: 84dfe36 (mptcp: send out dedicated ADD_ADDR packet) Signed-off-by: Geliang Tang <[email protected]> Reviewed-by: Mat Martineau <[email protected]> Link: https://lore.kernel.org/r/ccca4e8f01457a1b495c5d612ed16c5f7a585706.1608010058.git.geliangtang@gmail.com Signed-off-by: Jakub Kicinski <[email protected]>

…ULL pointer When function return fail to __ath11k_mac_register after success called ieee80211_register_hw, then it set wiphy->dev.parent to NULL by SET_IEEE80211_DEV(ar->hw, NULL) in end of __ath11k_mac_register, then cfg80211_get_drvinfo will be called by below call stack, but the wiphy->dev.parent is NULL, so kernel crash. Call stack to cfg80211_get_drvinfo: NetworkManager 826 [001] 6696.731371: probe:cfg80211_get_drvinfo: (ffffffffc107d8f0) ffffffffc107d8f1 cfg80211_get_drvinfo+0x1 (/lib/modules/5.10.0-rc1-wt-ath+/kernel/net/wireless-back/cfg80211.ko) ffffffff9d8fc529 ethtool_get_drvinfo+0x99 (vmlinux) ffffffff9d90080e dev_ethtool+0x1dbe (vmlinux) ffffffff9d8b88f7 dev_ioctl+0xb7 (vmlinux) ffffffff9d8668de sock_do_ioctl+0xae (vmlinux) ffffffff9d866d60 sock_ioctl+0x350 (vmlinux) ffffffff9d2ca30e __x64_sys_ioctl+0x8e (vmlinux) ffffffff9da0dda3 do_syscall_64+0x33 (vmlinux) ffffffff9dc0008c entry_SYSCALL_64_after_hwframe+0x44 (vmlinux) 7feb5f673007 __GI___ioctl+0x7 (/lib/x86_64-linux-gnu/libc-2.23.so) 0 [unknown] ([unknown]) Code of cfg80211_get_drvinfo, the pdev which is wiphy->dev.parent is NULL when kernel crash: void cfg80211_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info) { struct wireless_dev *wdev = dev->ieee80211_ptr; struct device *pdev = wiphy_dev(wdev->wiphy); if (pdev->driver) .... kernel crash log: [ 973.619550] ath11k_pci 0000:05:00.0: failed to perform regd update : -16 [ 973.619555] ath11k_pci 0000:05:00.0: ath11k regd update failed: -16 [ 973.619566] ath11k_pci 0000:05:00.0: failed register the radio with mac80211: -16 [ 973.619618] ath11k_pci 0000:05:00.0: failed to create pdev core: -16 [ 973.636035] BUG: kernel NULL pointer dereference, address: 0000000000000068 [ 973.636046] #PF: supervisor read access in kernel mode [ 973.636050] #PF: error_code(0x0000) - not-present page [ 973.636054] PGD 800000012452e067 P4D 800000012452e067 PUD 12452d067 PMD 0 [ 973.636064] Oops: 0000 [#1] SMP PTI [ 973.636072] CPU: 3 PID: 848 Comm: NetworkManager Kdump: loaded Tainted: G W OE 5.10.0-rc1-wt-ath+ #24 [ 973.636076] Hardware name: LENOVO 418065C/418065C, BIOS 83ET63WW (1.33 ) 07/29/2011 [ 973.636161] RIP: 0010:cfg80211_get_drvinfo+0x25/0xd0 [cfg80211] [ 973.636169] Code: e9 c9 fe ff ff 66 66 66 66 90 55 53 ba 20 00 00 00 48 8b af 08 03 00 00 48 89 f3 48 8d 7e 04 48 8b 45 00 48 8b 80 90 01 00 00 <48> 8b 40 68 48 85 c0 0f 84 8d 00 00 00 48 8b 30 e8 a6 cc 72 c7 48 [ 973.636174] RSP: 0018:ffffaafb4040bbe0 EFLAGS: 00010286 [ 973.636180] RAX: 0000000000000000 RBX: ffffaafb4040bbfc RCX: 0000000000000000 [ 973.636184] RDX: 0000000000000020 RSI: ffffaafb4040bbfc RDI: ffffaafb4040bc00 [ 973.636188] RBP: ffff8a84c9568950 R08: 722d302e30312e35 R09: 74612d74772d3163 [ 973.636192] R10: 3163722d302e3031 R11: 2b6874612d74772d R12: ffffaafb4040bbfc [ 973.636196] R13: 00007ffe453707c0 R14: ffff8a84c9568000 R15: 0000000000000000 [ 973.636202] FS: 00007fd3d179b940(0000) GS:ffff8a84fa2c0000(0000) knlGS:0000000000000000 [ 973.636206] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 973.636211] CR2: 0000000000000068 CR3: 00000001153b6002 CR4: 00000000000606e0 [ 973.636215] Call Trace: [ 973.636234] ethtool_get_drvinfo+0x99/0x1f0 [ 973.636246] dev_ethtool+0x1dbe/0x2be0 [ 973.636256] ? mntput_no_expire+0x35/0x220 [ 973.636264] ? inet_ioctl+0x1ce/0x200 [ 973.636274] ? tomoyo_path_number_perm+0x68/0x1d0 [ 973.636282] ? kmem_cache_alloc+0x3cb/0x430 [ 973.636290] ? dev_ioctl+0xb7/0x570 [ 973.636295] dev_ioctl+0xb7/0x570 [ 973.636307] sock_do_ioctl+0xae/0x150 [ 973.636315] ? sock_ioctl+0x350/0x3c0 [ 973.636319] sock_ioctl+0x350/0x3c0 [ 973.636332] ? __x64_sys_ioctl+0x8e/0xd0 [ 973.636339] ? dlci_ioctl_set+0x30/0x30 [ 973.636346] __x64_sys_ioctl+0x8e/0xd0 [ 973.636359] do_syscall_64+0x33/0x80 [ 973.636368] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Sequence of function call when wlan load for success case when function __ath11k_mac_register return 0: kworker/u16:3-e 2922 [001] 6696.729734: probe:ieee80211_register_hw: (ffffffffc116ae60) kworker/u16:3-e 2922 [001] 6696.730210: probe:ieee80211_if_add: (ffffffffc1185cc0) NetworkManager 826 [001] 6696.731345: probe:ethtool_get_drvinfo: (ffffffff9d8fc490) NetworkManager 826 [001] 6696.731371: probe:cfg80211_get_drvinfo: (ffffffffc107d8f0) NetworkManager 826 [001] 6696.731639: probe:ethtool_get_drvinfo: (ffffffff9d8fc490) NetworkManager 826 [001] 6696.731653: probe:cfg80211_get_drvinfo: (ffffffffc107d8f0) NetworkManager 826 [001] 6696.732866: probe:ethtool_get_drvinfo: (ffffffff9d8fc490) NetworkManager 826 [001] 6696.732893: probe:cfg80211_get_drvinfo: (ffffffffc107d8f0) systemd-udevd 3850 [003] 6696.737199: probe:ethtool_get_drvinfo: (ffffffff9d8fc490) systemd-udevd 3850 [003] 6696.737226: probe:cfg80211_get_drvinfo: (ffffffffc107d8f0) NetworkManager 826 [000] 6696.759950: probe:ethtool_get_drvinfo: (ffffffff9d8fc490) NetworkManager 826 [000] 6696.759967: probe:cfg80211_get_drvinfo: (ffffffffc107d8f0) NetworkManager 826 [000] 6696.760057: probe:ethtool_get_drvinfo: (ffffffff9d8fc490) NetworkManager 826 [000] 6696.760062: probe:cfg80211_get_drvinfo: (ffffffffc107d8f0) After apply this patch, kernel crash gone, and below is the test case's sequence of function call and log when wlan load with fail by function ath11k_regd_update, and __ath11k_mac_register return fail: kworker/u16:5-e 192 [001] 215.174388: probe:ieee80211_register_hw: (ffffffffc1131e60) kworker/u16:5-e 192 [000] 215.174973: probe:ieee80211_if_add: (ffffffffc114ccc0) NetworkManager 846 [001] 215.175857: probe:ethtool_get_drvinfo: (ffffffff928fc490) kworker/u16:5-e 192 [000] 215.175867: probe:ieee80211_unregister_hw: (ffffffffc1131970) NetworkManager 846 [001] 215.175880: probe:cfg80211_get_drvinfo: (ffffffffc107f8f0) NetworkManager 846 [001] 215.176105: probe:ethtool_get_drvinfo: (ffffffff928fc490) NetworkManager 846 [001] 215.176118: probe:cfg80211_get_drvinfo: (ffffffffc107f8f0) [ 215.175859] ath11k_pci 0000:05:00.0: ath11k regd update failed: -16 NetworkManager 846 [001] 215.196420: probe:ethtool_get_drvinfo: (ffffffff928fc490) NetworkManager 846 [001] 215.196430: probe:cfg80211_get_drvinfo: (ffffffffc107f8f0) [ 215.258598] ath11k_pci 0000:05:00.0: failed register the radio with mac80211: -16 [ 215.258613] ath11k_pci 0000:05:00.0: failed to create pdev core: -16 When ath11k_regd_update or ath11k_debugfs_register return fail, function ieee80211_unregister_hw of mac80211 will be called, then it will wait untill cfg80211_get_drvinfo finished, the wiphy->dev.parent is not NULL at this moment, after that, it set wiphy->dev.parent to NULL by SET_IEEE80211_DEV(ar->hw, NULL) in end of __ath11k_mac_register, so not happen kernel crash. Tested-on: QCA6390 hw2.0 PCI WLAN.HST.1.0.1-01740-QCAHSTSWPLZ_V2_TO_X86-1 Signed-off-by: Wen Gong <[email protected]> Signed-off-by: Kalle Valo <[email protected]> Link: https://lore.kernel.org/r/[email protected]

Pablo Neira Ayuso says: ==================== netfilter: flowtable enhancements [ This is v2 that includes documentation enhancements, including existing limitations. This is a rebase on top on net-next. ] The following patchset augments the Netfilter flowtable fastpath to support for network topologies that combine IP forwarding, bridge, classic VLAN devices, bridge VLAN filtering, DSA and PPPoE. This includes support for the flowtable software and hardware datapaths. The following pictures provides an example scenario: fast path! .------------------------. / \ | IP forwarding | | / \ \/ | br0 wan ..... eth0 . / \ host C -> veth1 veth2 . switch/router . . eth0 host A The bridge master device 'br0' has an IP address and a DHCP server is also assumed to be running to provide connectivity to host A which reaches the Internet through 'br0' as default gateway. Then, packet enters the IP forwarding path and Netfilter is used to NAT the packets before they leave through the wan device. The general idea is to accelerate forwarding by building a fast path that takes packets from the ingress path of the bridge port and place them in the egress path of the wan device (and vice versa). Hence, skipping the classic bridge and IP stack paths. ** Patch from #1 to #6 add the infrastructure which describes the list of netdevice hops to reach a given destination MAC address in the local network topology. Patch #1 adds dev_fill_forward_path() and .ndo_fill_forward_path() to netdev_ops. Patch #2 adds .ndo_fill_forward_path for vlan devices, which provides the next device hop via vlan->real_dev, the vlan ID and the protocol. Patch #3 adds .ndo_fill_forward_path for bridge devices, which allows to make lookups to the FDB to locate the next device hop (bridge port) in the forwarding path. Patch #4 extends bridge .ndo_fill_forward_path to support for bridge VLAN filtering. Patch #5 adds .ndo_fill_forward_path for PPPoE devices. Patch #6 adds .ndo_fill_forward_path for DSA. Patches from #7 to #14 update the flowtable software datapath: Patch #7 adds the transmit path type field to the flow tuple. Two transmit paths are supported so far: the neighbour and the xfrm transmit paths. Patch #8 and #9 update the flowtable datapath to use dev_fill_forward_path() to obtain the real ingress/egress device for the flowtable datapath. This adds the new ethernet xmit direct path to the flowtable. Patch #10 adds native flowtable VLAN support (up to 2 VLAN tags) through dev_fill_forward_path(). The flowtable stores the VLAN id and protocol in the flow tuple. Patch #11 adds native flowtable bridge VLAN filter support through dev_fill_forward_path(). Patch #12 adds native flowtable bridge PPPoE through dev_fill_forward_path(). Patch #13 adds DSA support through dev_fill_forward_path(). Patch #14 extends flowtable selftests to cover for flowtable software datapath enhancements. ** Patches from #15 to #20 update the flowtable hardware offload datapath: Patch #15 extends the flowtable hardware offload to support for the direct ethernet xmit path. This also includes VLAN support. Patch #16 stores the egress real device in the flow tuple. The software flowtable datapath uses dev_hard_header() to transmit packets, hence it might refer to VLAN/DSA/PPPoE software device, not the real ethernet device. Patch #17 deals with switchdev PVID hardware offload to skip it on egress. Patch #18 adds FLOW_ACTION_PPPOE_PUSH to the flow_offload action API. Patch #19 extends the flowtable hardware offload to support for PPPoE Patch #20 adds TC_SETUP_FT support for DSA. ** Patches from #20 to #23: Felix Fietkau adds a new driver which support hardware offload for the mtk PPE engine through the existing flow offload API which supports for the flowtable enhancements coming in this batch. Patch #24 extends the documentation and describe existing limitations. Please, apply, thanks. ==================== Signed-off-by: David S. Miller <[email protected]>

The perf_buffer fails on system with offline cpus: # test_progs -t perf_buffer test_perf_buffer:PASS:nr_cpus 0 nsec test_perf_buffer:PASS:nr_on_cpus 0 nsec test_perf_buffer:PASS:skel_load 0 nsec test_perf_buffer:PASS:attach_kprobe 0 nsec test_perf_buffer:PASS:perf_buf__new 0 nsec test_perf_buffer:PASS:epoll_fd 0 nsec skipping offline CPU #24 skipping offline CPU #25 skipping offline CPU #26 skipping offline CPU #27 skipping offline CPU #28 skipping offline CPU #29 skipping offline CPU #30 skipping offline CPU #31 test_perf_buffer:PASS:perf_buffer__poll 0 nsec test_perf_buffer:PASS:seen_cpu_cnt 0 nsec test_perf_buffer:FAIL:buf_cnt got 24, expected 32 Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED Changing the test to check online cpus instead of possible. Signed-off-by: Jiri Olsa <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Acked-by: John Fastabend <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]

When bringing down the netdevice or system shutdown, a panic can be triggered while accessing the sysfs path because the device is already removed. [ 755.549084] mlx5_core 0000:12:00.1: Shutdown was called [ 756.404455] mlx5_core 0000:12:00.0: Shutdown was called ... [ 757.937260] BUG: unable to handle kernel NULL pointer dereference at (null) [ 758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280 crash> bt ... PID: 12649 TASK: ffff8924108f2100 CPU: 1 COMMAND: "amsd" ... #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778 [exception RIP: dma_pool_alloc+0x1ab] RIP: ffffffff8ee11acb RSP: ffff89240e1a3968 RFLAGS: 00010046 RAX: 0000000000000246 RBX: ffff89243d874100 RCX: 0000000000001000 RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff89243d874090 RBP: ffff89240e1a39c0 R8: 000000000001f080 R9: ffff8905ffc03c00 R10: ffffffffc04680d4 R11: ffffffff8edde9fd R12: 00000000000080d0 R13: ffff89243d874090 R14: ffff89243d874080 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core] #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core] #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core] #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core] #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core] #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core] #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core] #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46 #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208 #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3 #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596 #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10 #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5 #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92 crash> net_device.state ffff89443b0c0000 state = 0x5 (__LINK_STATE_START| __LINK_STATE_NOCARRIER) To prevent this scenario, we also make sure that the netdevice is present. Signed-off-by: suresh kumar <[email protected]> Signed-off-by: David S. Miller <[email protected]>

The BPF STX/LDX instruction uses offset relative to the FP to address stack space. Since the BPF_FP locates at the top of the frame, the offset is usually a negative number. However, arm64 str/ldr immediate instruction requires that offset be a positive number. Therefore, this patch tries to convert the offsets. The method is to find the negative offset furthest from the FP firstly. Then add it to the FP, calculate a bottom position, called FPB, and then adjust the offsets in other STR/LDX instructions relative to FPB. FPB is saved using the callee-saved register x27 of arm64 which is not used yet. Before adjusting the offset, the patch checks every instruction to ensure that the FP does not change in run-time. If the FP may change, no offset is adjusted. For example, for the following bpftrace command: bpftrace -e 'kprobe:do_sys_open { printf("opening: %s\n", str(arg1)); }' Without this patch, jited code(fragment): 0: bti c 4: stp x29, x30, [sp, #-16]! 8: mov x29, sp c: stp x19, x20, [sp, #-16]! 10: stp x21, x22, [sp, #-16]! 14: stp x25, x26, [sp, #-16]! 18: mov x25, sp 1c: mov x26, #0x0 // #0 20: bti j 24: sub sp, sp, #0x90 28: add x19, x0, #0x0 2c: mov x0, #0x0 // #0 30: mov x10, #0xffffffffffffff78 // #-136 34: str x0, [x25, x10] 38: mov x10, #0xffffffffffffff80 // #-128 3c: str x0, [x25, x10] 40: mov x10, #0xffffffffffffff88 // #-120 44: str x0, [x25, x10] 48: mov x10, #0xffffffffffffff90 // #-112 4c: str x0, [x25, x10] 50: mov x10, #0xffffffffffffff98 // #-104 54: str x0, [x25, x10] 58: mov x10, #0xffffffffffffffa0 // #-96 5c: str x0, [x25, x10] 60: mov x10, #0xffffffffffffffa8 // #-88 64: str x0, [x25, x10] 68: mov x10, #0xffffffffffffffb0 // #-80 6c: str x0, [x25, x10] 70: mov x10, #0xffffffffffffffb8 // #-72 74: str x0, [x25, x10] 78: mov x10, #0xffffffffffffffc0 // #-64 7c: str x0, [x25, x10] 80: mov x10, #0xffffffffffffffc8 // #-56 84: str x0, [x25, x10] 88: mov x10, #0xffffffffffffffd0 // #-48 8c: str x0, [x25, x10] 90: mov x10, #0xffffffffffffffd8 // #-40 94: str x0, [x25, x10] 98: mov x10, #0xffffffffffffffe0 // #-32 9c: str x0, [x25, x10] a0: mov x10, #0xffffffffffffffe8 // #-24 a4: str x0, [x25, x10] a8: mov x10, #0xfffffffffffffff0 // #-16 ac: str x0, [x25, x10] b0: mov x10, #0xfffffffffffffff8 // #-8 b4: str x0, [x25, x10] b8: mov x10, #0x8 // #8 bc: ldr x2, [x19, x10] [...] With this patch, jited code(fragment): 0: bti c 4: stp x29, x30, [sp, #-16]! 8: mov x29, sp c: stp x19, x20, [sp, #-16]! 10: stp x21, x22, [sp, #-16]! 14: stp x25, x26, [sp, #-16]! 18: stp x27, x28, [sp, #-16]! 1c: mov x25, sp 20: sub x27, x25, #0x88 24: mov x26, #0x0 // #0 28: bti j 2c: sub sp, sp, #0x90 30: add x19, x0, #0x0 34: mov x0, #0x0 // #0 38: str x0, [x27] 3c: str x0, [x27, #8] 40: str x0, [x27, #16] 44: str x0, [x27, #24] 48: str x0, [x27, #32] 4c: str x0, [x27, #40] 50: str x0, [x27, #48] 54: str x0, [x27, #56] 58: str x0, [x27, #64] 5c: str x0, [x27, #72] 60: str x0, [x27, #80] 64: str x0, [x27, #88] 68: str x0, [x27, #96] 6c: str x0, [x27, #104] 70: str x0, [x27, #112] 74: str x0, [x27, #120] 78: str x0, [x27, #128] 7c: ldr x2, [x19, #8] [...] Signed-off-by: Xu Kuohai <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]

During stress test with attaching and detaching VF from KVM and simultaneously changing VFs spoofcheck and trust there was a call trace in ice_reset_vf that VF's VSI is null. [145237.352797] WARNING: CPU: 46 PID: 840629 at drivers/net/ethernet/intel/ice/ice_vf_lib.c:508 ice_reset_vf+0x3d6/0x410 [ice] [145237.352851] Modules linked in: ice(E) vfio_pci vfio_pci_core vfio_virqfd vfio_iommu_type1 vfio iavf dm_mod xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink tun bridge stp llc sunrpc intel_rapl_msr intel_rapl_common sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm iTCO_wdt iTC O_vendor_support irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel rapl ipmi_si intel_cstate ipmi_devintf joydev intel_uncore m ei_me ipmi_msghandler i2c_i801 pcspkr mei lpc_ich ioatdma i2c_smbus acpi_pad acpi_power_meter ip_tables xfs libcrc32c i2c_algo_bit drm_sh mem_helper drm_kms_helper sd_mod t10_pi crc64_rocksoft syscopyarea crc64 sysfillrect sg sysimgblt fb_sys_fops drm i40e ixgbe ahci libahci libata crc32c_intel mdio dca wmi fuse [last unloaded: ice] [145237.352917] CPU: 46 PID: 840629 Comm: kworker/46:2 Tainted: G S W I E 5.19.0-rc6+ #24 [145237.352921] Hardware name: Intel Corporation S2600WTT/S2600WTT, BIOS SE5C610.86B.01.01.0008.021120151325 02/11/2015 [145237.352923] Workqueue: ice ice_service_task [ice] [145237.352948] RIP: 0010:ice_reset_vf+0x3d6/0x410 [ice] [145237.352984] Code: 30 ec f3 cc e9 28 fd ff ff 0f b7 4b 50 48 c7 c2 48 19 9c c0 4c 89 ee 48 c7 c7 30 fe 9e c0 e8 d1 21 9d cc 31 c0 e9 a 9 fe ff ff <0f> 0b b8 ea ff ff ff e9 c1 fc ff ff 0f 0b b8 fb ff ff ff e9 91 fe [145237.352987] RSP: 0018:ffffb453e257fdb8 EFLAGS: 00010246 [145237.352990] RAX: ffff8bd0040181c0 RBX: ffff8be68db8f800 RCX: 0000000000000000 [145237.352991] RDX: 000000000000ffff RSI: 0000000000000000 RDI: ffff8be68db8f800 [145237.352993] RBP: ffff8bd0040181c0 R08: 0000000000001000 R09: ffff8bcfd520e000 [145237.352995] R10: 0000000000000000 R11: 00008417b5ab0bc0 R12: 0000000000000005 [145237.352996] R13: ffff8bcee061c0d0 R14: ffff8bd004019640 R15: 0000000000000000 [145237.352998] FS: 0000000000000000(0000) GS:ffff8be5dfb00000(0000) knlGS:0000000000000000 [145237.353000] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [145237.353002] CR2: 00007fd81f651d68 CR3: 0000001a0fe10001 CR4: 00000000001726e0 [145237.353003] Call Trace: [145237.353008] <TASK> [145237.353011] ice_process_vflr_event+0x8d/0xb0 [ice] [145237.353049] ice_service_task+0x79f/0xef0 [ice] [145237.353074] process_one_work+0x1c8/0x390 [145237.353081] ? process_one_work+0x390/0x390 [145237.353084] worker_thread+0x30/0x360 [145237.353087] ? process_one_work+0x390/0x390 [145237.353090] kthread+0xe8/0x110 [145237.353094] ? kthread_complete_and_exit+0x20/0x20 [145237.353097] ret_from_fork+0x22/0x30 [145237.353103] </TASK> Remove WARN_ON() from check if VSI is null in ice_reset_vf. Add "VF is already removed\n" in dev_dbg(). This WARN_ON() is unnecessary and causes call trace, despite that call trace, driver still works. There is no need for this warn because this piece of code is responsible for disabling VF's Tx/Rx queues when VF is disabled, but when VF is already removed there is no need to do reset or disable queues. Fixes: efe4186 ("ice: Fix memory corruption in VF driver") Signed-off-by: Michal Jaron <[email protected]> Signed-off-by: Jedrzej Jagielski <[email protected]> Tested-by: Marek Szlosek <[email protected]> Signed-off-by: Tony Nguyen <[email protected]>

When we try to transmit an skb with metadata_dst attached (i.e. dst->dev == NULL) through xfrm interface we can hit a null pointer dereference[1] in xfrmi_xmit2() -> xfrm_lookup_with_ifid() due to the check for a loopback skb device when there's no policy which dereferences dst->dev unconditionally. Not having dst->dev can be interepreted as it not being a loopback device, so just add a check for a null dst_orig->dev. With this fix xfrm interface's Tx error counters go up as usual. [1] net-next calltrace captured via netconsole: BUG: kernel NULL pointer dereference, address: 00000000000000c0 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 1 PID: 7231 Comm: ping Kdump: loaded Not tainted 5.19.0+ #24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-1.fc36 04/01/2014 RIP: 0010:xfrm_lookup_with_ifid+0x5eb/0xa60 Code: 8d 74 24 38 e8 26 a4 37 00 48 89 c1 e9 12 fc ff ff 49 63 ed 41 83 fd be 0f 85 be 01 00 00 41 be ff ff ff ff 45 31 ed 48 8b 03 <f6> 80 c0 00 00 00 08 75 0f 41 80 bc 24 19 0d 00 00 01 0f 84 1e 02 RSP: 0018:ffffb0db82c679f0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffd0db7fcad430 RCX: ffffb0db82c67a10 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb0db82c67a80 RBP: ffffb0db82c67a80 R08: ffffb0db82c67a14 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8fa449667dc8 R12: ffffffff966db880 R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000 FS: 00007ff35c83f000(0000) GS:ffff8fa478480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000c0 CR3: 000000001ebb7000 CR4: 0000000000350ee0 Call Trace: <TASK> xfrmi_xmit+0xde/0x460 ? tcf_bpf_act+0x13d/0x2a0 dev_hard_start_xmit+0x72/0x1e0 __dev_queue_xmit+0x251/0xd30 ip_finish_output2+0x140/0x550 ip_push_pending_frames+0x56/0x80 raw_sendmsg+0x663/0x10a0 ? try_charge_memcg+0x3fd/0x7a0 ? __mod_memcg_lruvec_state+0x93/0x110 ? sock_sendmsg+0x30/0x40 sock_sendmsg+0x30/0x40 __sys_sendto+0xeb/0x130 ? handle_mm_fault+0xae/0x280 ? do_user_addr_fault+0x1e7/0x680 ? kvm_read_and_reset_apf_flags+0x3b/0x50 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7ff35cac1366 Code: eb 0b 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 72 c3 90 55 48 83 ec 30 44 89 4c 24 2c 4c 89 RSP: 002b:00007fff738e4028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fff738e57b0 RCX: 00007ff35cac1366 RDX: 0000000000000040 RSI: 0000557164e4b450 RDI: 0000000000000003 RBP: 0000557164e4b450 R08: 00007fff738e7a2c R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 00007fff738e5770 R14: 00007fff738e4030 R15: 0000001d00000001 </TASK> Modules linked in: netconsole veth br_netfilter bridge bonding virtio_net [last unloaded: netconsole] CR2: 00000000000000c0 CC: Steffen Klassert <[email protected]> CC: Daniel Borkmann <[email protected]> Fixes: 2d151d3 ("xfrm: Add possibility to set the default to block if we have no policy") Signed-off-by: Nikolay Aleksandrov <[email protected]> Signed-off-by: Steffen Klassert <[email protected]>

The cited commit adds a compeletion to remove dependency on rtnl lock. But it causes a deadlock for multiple encapsulations: crash> bt ffff8aece8a64000 PID: 1514557 TASK: ffff8aece8a64000 CPU: 3 COMMAND: "tc" #0 [ffffa6d14183f368] __schedule at ffffffffb8ba7f45 #1 [ffffa6d14183f3f8] schedule at ffffffffb8ba8418 #2 [ffffa6d14183f418] schedule_preempt_disabled at ffffffffb8ba8898 #3 [ffffa6d14183f428] __mutex_lock at ffffffffb8baa7f8 #4 [ffffa6d14183f4d0] mutex_lock_nested at ffffffffb8baabeb #5 [ffffa6d14183f4e0] mlx5e_attach_encap at ffffffffc0f48c17 [mlx5_core] #6 [ffffa6d14183f628] mlx5e_tc_add_fdb_flow at ffffffffc0f39680 [mlx5_core] #7 [ffffa6d14183f688] __mlx5e_add_fdb_flow at ffffffffc0f3b636 [mlx5_core] #8 [ffffa6d14183f6f0] mlx5e_tc_add_flow at ffffffffc0f3bcdf [mlx5_core] #9 [ffffa6d14183f728] mlx5e_configure_flower at ffffffffc0f3c1d1 [mlx5_core] #10 [ffffa6d14183f790] mlx5e_rep_setup_tc_cls_flower at ffffffffc0f3d529 [mlx5_core] #11 [ffffa6d14183f7a0] mlx5e_rep_setup_tc_cb at ffffffffc0f3d714 [mlx5_core] #12 [ffffa6d14183f7b0] tc_setup_cb_add at ffffffffb8931bb8 #13 [ffffa6d14183f810] fl_hw_replace_filter at ffffffffc0dae901 [cls_flower] #14 [ffffa6d14183f8d8] fl_change at ffffffffc0db5c57 [cls_flower] #15 [ffffa6d14183f970] tc_new_tfilter at ffffffffb8936047 #16 [ffffa6d14183fac8] rtnetlink_rcv_msg at ffffffffb88c7c31 #17 [ffffa6d14183fb50] netlink_rcv_skb at ffffffffb8942853 #18 [ffffa6d14183fbc0] rtnetlink_rcv at ffffffffb88c1835 #19 [ffffa6d14183fbd0] netlink_unicast at ffffffffb8941f27 #20 [ffffa6d14183fc18] netlink_sendmsg at ffffffffb8942245 #21 [ffffa6d14183fc98] sock_sendmsg at ffffffffb887d482 #22 [ffffa6d14183fcb8] ____sys_sendmsg at ffffffffb887d81a #23 [ffffa6d14183fd38] ___sys_sendmsg at ffffffffb88806e2 #24 [ffffa6d14183fe90] __sys_sendmsg at ffffffffb88807a2 #25 [ffffa6d14183ff28] __x64_sys_sendmsg at ffffffffb888080f #26 [ffffa6d14183ff38] do_syscall_64 at ffffffffb8b9b6a8 #27 [ffffa6d14183ff50] entry_SYSCALL_64_after_hwframe at ffffffffb8c0007c crash> bt 0xffff8aeb07544000 PID: 1110766 TASK: ffff8aeb07544000 CPU: 0 COMMAND: "kworker/u20:9" #0 [ffffa6d14e6b7bd8] __schedule at ffffffffb8ba7f45 #1 [ffffa6d14e6b7c68] schedule at ffffffffb8ba8418 #2 [ffffa6d14e6b7c88] schedule_timeout at ffffffffb8baef88 #3 [ffffa6d14e6b7d10] wait_for_completion at ffffffffb8ba968b #4 [ffffa6d14e6b7d60] mlx5e_take_all_encap_flows at ffffffffc0f47ec4 [mlx5_core] #5 [ffffa6d14e6b7da0] mlx5e_rep_update_flows at ffffffffc0f3e734 [mlx5_core] #6 [ffffa6d14e6b7df8] mlx5e_rep_neigh_update at ffffffffc0f400bb [mlx5_core] #7 [ffffa6d14e6b7e50] process_one_work at ffffffffb80acc9c #8 [ffffa6d14e6b7ed0] worker_thread at ffffffffb80ad012 #9 [ffffa6d14e6b7f10] kthread at ffffffffb80b615d #10 [ffffa6d14e6b7f50] ret_from_fork at ffffffffb8001b2f After the first encap is attached, flow will be added to encap entry's flows list. If neigh update is running at this time, the following encaps of the flow can't hold the encap_tbl_lock and sleep. If neigh update thread is waiting for that flow's init_done, deadlock happens. Fix it by holding lock outside of the for loop. If neigh update is running, prevent encap flows from offloading. Since the lock is held outside of the for loop, concurrent creation of encap entries is not allowed. So remove unnecessary wait_for_completion call for res_ready. Fixes: 95435ad ("net/mlx5e: Only access fully initialized flows in neigh update") Signed-off-by: Chris Mi <[email protected]> Reviewed-by: Roi Dayan <[email protected]> Reviewed-by: Vlad Buslov <[email protected]> Signed-off-by: Saeed Mahameed <[email protected]>

The following processes run into a deadlock. CPU 41 was waiting for CPU 29 to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29 was hung by that spinlock with IRQs disabled. PID: 17360 TASK: ffff95c1090c5c40 CPU: 41 COMMAND: "mrdiagd" !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0 !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0 !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0 # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0 # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0 # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0 # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0 # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0 # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0 # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0 #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0 #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0 #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0 #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0 #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0 #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0 #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0 #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0 #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0 #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0 #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0 #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0 #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0 #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0 #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0 #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0 #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0 #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0 PID: 17355 TASK: ffff95c1090c3d80 CPU: 29 COMMAND: "mrdiagd" !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0 !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0 # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0 # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0 # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0 # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0 # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0 # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0 # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0 # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0 #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0 #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0 #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0 #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0 #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0 #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0 #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0 #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0 The lock is used to synchronize different sysfs operations, it doesn't protect any resource that will be touched by an interrupt. Consequently it's not required to disable IRQs. Replace the spinlock with a mutex to fix the deadlock. Signed-off-by: Junxiao Bi <[email protected]> Link: https://lore.kernel.org/r/[email protected] Reviewed-by: Mike Christie <[email protected]> Cc: [email protected] Signed-off-by: Martin K. Petersen <[email protected]>

The current implementation of the mov instruction with sign extension has the following problems: 1. It clobbers the source register if it is not stacked because it sign extends the source and then moves it to the destination. 2. If the dst_reg is stacked, the current code doesn't write the value back in case of 64-bit mov. 3. There is room for improvement by emitting fewer instructions. The steps for fixing this and the instructions emitted by the JIT are explained below with examples in all combinations: Case A: offset == 32: ===================== Case A.1: src and dst are stacked registers: -------------------------------------------- 1. Load src_lo into tmp_lo 2. Store tmp_lo into dst_lo 3. Sign extend tmp_lo into tmp_hi 4. Store tmp_hi to dst_hi Example: r3 = (s32)r3 r3 is a stacked register ldr r6, [r11, #-16] // Load r3_lo into tmp_lo // str to dst_lo is not emitted because src_lo == dst_lo asr r7, r6, #31 // Sign extend tmp_lo into tmp_hi str r7, [r11, #-12] // Store tmp_hi into r3_hi Case A.2: src is stacked but dst is not: ---------------------------------------- 1. Load src_lo into dst_lo 2. Sign extend dst_lo into dst_hi Example: r6 = (s32)r3 r6 maps to {ARM_R5, ARM_R4} and r3 is stacked ldr r4, [r11, #-16] // Load r3_lo into r6_lo asr r5, r4, #31 // Sign extend r6_lo into r6_hi Case A.3: src is not stacked but dst is stacked: ------------------------------------------------ 1. Store src_lo into dst_lo 2. Sign extend src_lo into tmp_hi 3. Store tmp_hi to dst_hi Example: r3 = (s32)r6 r3 is stacked and r6 maps to {ARM_R5, ARM_R4} str r4, [r11, #-16] // Store r6_lo to r3_lo asr r7, r4, #31 // Sign extend r6_lo into tmp_hi str r7, [r11, #-12] // Store tmp_hi to dest_hi Case A.4: Both src and dst are not stacked: ------------------------------------------- 1. Mov src_lo into dst_lo 2. Sign extend src_lo into dst_hi Example: (bf) r6 = (s32)r6 r6 maps to {ARM_R5, ARM_R4} // Mov not emitted because dst == src asr r5, r4, #31 // Sign extend r6_lo into r6_hi Case B: offset != 32: ===================== Case B.1: src and dst are stacked registers: -------------------------------------------- 1. Load src_lo into tmp_lo 2. Sign extend tmp_lo according to offset. 3. Store tmp_lo into dst_lo 4. Sign extend tmp_lo into tmp_hi 5. Store tmp_hi to dst_hi Example: r9 = (s8)r3 r9 and r3 are both stacked registers ldr r6, [r11, #-16] // Load r3_lo into tmp_lo lsl r6, r6, #24 // Sign extend tmp_lo asr r6, r6, #24 // .. str r6, [r11, #-56] // Store tmp_lo to r9_lo asr r7, r6, #31 // Sign extend tmp_lo to tmp_hi str r7, [r11, #-52] // Store tmp_hi to r9_hi Case B.2: src is stacked but dst is not: ---------------------------------------- 1. Load src_lo into dst_lo 2. Sign extend dst_lo according to offset. 3. Sign extend tmp_lo into dst_hi Example: r6 = (s8)r3 r6 maps to {ARM_R5, ARM_R4} and r3 is stacked ldr r4, [r11, #-16] // Load r3_lo to r6_lo lsl r4, r4, #24 // Sign extend r6_lo asr r4, r4, #24 // .. asr r5, r4, #31 // Sign extend r6_lo into r6_hi Case B.3: src is not stacked but dst is stacked: ------------------------------------------------ 1. Sign extend src_lo into tmp_lo according to offset. 2. Store tmp_lo into dst_lo. 3. Sign extend src_lo into tmp_hi. 4. Store tmp_hi to dst_hi. Example: r3 = (s8)r1 r3 is stacked and r1 maps to {ARM_R3, ARM_R2} lsl r6, r2, #24 // Sign extend r1_lo to tmp_lo asr r6, r6, #24 // .. str r6, [r11, #-16] // Store tmp_lo to r3_lo asr r7, r6, #31 // Sign extend tmp_lo to tmp_hi str r7, [r11, #-12] // Store tmp_hi to r3_hi Case B.4: Both src and dst are not stacked: ------------------------------------------- 1. Sign extend src_lo into dst_lo according to offset. 2. Sign extend dst_lo into dst_hi. Example: r6 = (s8)r1 r6 maps to {ARM_R5, ARM_R4} and r1 maps to {ARM_R3, ARM_R2} lsl r4, r2, #24 // Sign extend r1_lo to r6_lo asr r4, r4, #24 // .. asr r5, r4, #31 // Sign extend r6_lo to r6_hi Fixes: fc83265 ("arm32, bpf: add support for sign-extension mov instruction") Reported-by: [email protected] Signed-off-by: Puranjay Mohan <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Reviewed-by: Russell King (Oracle) <[email protected]> Closes: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/bpf/[email protected]

Inline calls to bpf_get_smp_processor_id() helper in the JIT by emitting a read from struct thread_info. The SP_EL0 system register holds the pointer to the task_struct and thread_info is the first member of this struct. We can read the cpu number from the thread_info. Here is how the ARM64 JITed assembly changes after this commit: ARM64 JIT =========== BEFORE AFTER -------- ------- int cpu = bpf_get_smp_processor_id(); int cpu = bpf_get_smp_processor_id(); mov x10, #0xfffffffffffff4d0 mrs x10, sp_el0 movk x10, #0x802b, lsl #16 ldr w7, [x10, #24] movk x10, #0x8000, lsl #32 blr x10 add x7, x0, #0x0 Performance improvement using benchmark[1] ./benchs/run_bench_trigger.sh glob-arr-inc arr-inc hash-inc +---------------+-------------------+-------------------+--------------+ | Name | Before | After | % change | |---------------+-------------------+-------------------+--------------| | glob-arr-inc | 23.380 ± 1.675M/s | 25.893 ± 0.026M/s | + 10.74% | | arr-inc | 23.928 ± 0.034M/s | 25.213 ± 0.063M/s | + 5.37% | | hash-inc | 12.352 ± 0.005M/s | 12.609 ± 0.013M/s | + 2.08% | +---------------+-------------------+-------------------+--------------+ [1] anakryiko/linux@8dec900975ef Signed-off-by: Puranjay Mohan <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>

Puranjay Mohan says: ==================== bpf: Inline helpers in arm64 and riscv JITs Changes in v5 -> v6: arm64 v5: https://lore.kernel.org/all/[email protected]/ riscv v2: https://lore.kernel.org/all/[email protected]/ - Combine riscv and arm64 changes in single series - Some coding style fixes Changes in v4 -> v5: v4: https://lore.kernel.org/all/[email protected]/ - Implement the inlining of the bpf_get_smp_processor_id() in the JIT. NOTE: This needs to be based on: https://lore.kernel.org/all/[email protected]/ to be built. Manual run of bpf-ci with this series rebased on above: kernel-patches/bpf#6929 Changes in v3 -> v4: v3: https://lore.kernel.org/all/[email protected]/ - Fix coding style issue related to C89 standards. Changes in v2 -> v3: v2: https://lore.kernel.org/all/[email protected]/ - Fixed the xlated dump of percpu mov to "r0 = &(void __percpu *)(r0)" - Made ARM64 and x86-64 use the same code for inlining. The only difference that remains is the per-cpu address of the cpu_number. Changes in v1 -> v2: v1: https://lore.kernel.org/all/[email protected]/ - Add a patch to inline bpf_get_smp_processor_id() - Fix an issue in MRS instruction encoding as pointed out by Will - Remove CONFIG_SMP check because arm64 kernel always compiles with CONFIG_SMP This series adds the support of internal only per-CPU instructions and inlines the bpf_get_smp_processor_id() helper call for ARM64 and RISC-V BPF JITs. Here is an example of calls to bpf_get_smp_processor_id() and percpu_array_map_lookup_elem() before and after this series on ARM64. BPF ===== BEFORE AFTER -------- ------- int cpu = bpf_get_smp_processor_id(); int cpu = bpf_get_smp_processor_id(); (85) call bpf_get_smp_processor_id#229032 (85) call bpf_get_smp_processor_id#8 p = bpf_map_lookup_elem(map, &zero); p = bpf_map_lookup_elem(map, &zero); (18) r1 = map[id:78] (18) r1 = map[id:153] (18) r2 = map[id:82][0]+65536 (18) r2 = map[id:157][0]+65536 (85) call percpu_array_map_lookup_elem#313512 (07) r1 += 496 (61) r0 = *(u32 *)(r2 +0) (35) if r0 >= 0x1 goto pc+5 (67) r0 <<= 3 (0f) r0 += r1 (79) r0 = *(u64 *)(r0 +0) (bf) r0 = &(void __percpu *)(r0) (05) goto pc+1 (b7) r0 = 0 ARM64 JIT =========== BEFORE AFTER -------- ------- int cpu = bpf_get_smp_processor_id(); int cpu = bpf_get_smp_processor_id(); mov x10, #0xfffffffffffff4d0 mrs x10, sp_el0 movk x10, #0x802b, lsl #16 ldr w7, [x10, #24] movk x10, #0x8000, lsl #32 blr x10 add x7, x0, #0x0 p = bpf_map_lookup_elem(map, &zero); p = bpf_map_lookup_elem(map, &zero); mov x0, #0xffff0003ffffffff mov x0, #0xffff0003ffffffff movk x0, #0xce5c, lsl #16 movk x0, #0xe0f3, lsl #16 movk x0, #0xca00 movk x0, #0x7c00 mov x1, #0xffff8000ffffffff mov x1, #0xffff8000ffffffff movk x1, #0x8bdb, lsl #16 movk x1, #0xb0c7, lsl #16 movk x1, #0x6000 movk x1, #0xe000 mov x10, #0xffffffffffff3ed0 add x0, x0, #0x1f0 movk x10, #0x802d, lsl #16 ldr w7, [x1] movk x10, #0x8000, lsl #32 cmp x7, #0x1 blr x10 b.cs 0x0000000000000090 add x7, x0, #0x0 lsl x7, x7, #3 add x7, x7, x0 ldr x7, [x7] mrs x10, tpidr_el1 add x7, x7, x10 b 0x0000000000000094 mov x7, #0x0 Performance improvement found using benchmark[1] ./benchs/run_bench_trigger.sh glob-arr-inc arr-inc hash-inc +---------------+-------------------+-------------------+--------------+ | Name | Before | After | % change | |---------------+-------------------+-------------------+--------------| | glob-arr-inc | 23.380 ± 1.675M/s | 25.893 ± 0.026M/s | + 10.74% | | arr-inc | 23.928 ± 0.034M/s | 25.213 ± 0.063M/s | + 5.37% | | hash-inc | 12.352 ± 0.005M/s | 12.609 ± 0.013M/s | + 2.08% | +---------------+-------------------+-------------------+--------------+ [1] anakryiko/linux@8dec900975ef RISCV64 JIT output for `call bpf_get_smp_processor_id` ======================================================= Before After -------- ------- auipc t1,0x848c ld a5,32(tp) jalr 604(t1) mv a5,a0 Benchmark using [1] on Qemu. ./benchs/run_bench_trigger.sh glob-arr-inc arr-inc hash-inc +---------------+------------------+------------------+--------------+ | Name | Before | After | % change | |---------------+------------------+------------------+--------------| | glob-arr-inc | 1.077 ± 0.006M/s | 1.336 ± 0.010M/s | + 24.04% | | arr-inc | 1.078 ± 0.002M/s | 1.332 ± 0.015M/s | + 23.56% | | hash-inc | 0.494 ± 0.004M/s | 0.653 ± 0.001M/s | + 32.18% | +---------------+------------------+------------------+--------------+ ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>

profile->parent->dents[AAFS_PROF_DIR] could be NULL only if its parent is made from __create_missing_ancestors(..) and 'ent->old' is NULL in aa_replace_profiles(..). In that case, it must return an error code and the code, -ENOENT represents its state that the path of its parent is not existed yet. BUG: kernel NULL pointer dereference, address: 0000000000000030 PGD 0 P4D 0 PREEMPT SMP PTI CPU: 4 PID: 3362 Comm: apparmor_parser Not tainted 6.8.0-24-generic #24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 RIP: 0010:aafs_create.constprop.0+0x7f/0x130 Code: 4c 63 e0 48 83 c4 18 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 45 31 d2 c3 cc cc cc cc <4d> 8b 55 30 4d 8d ba a0 00 00 00 4c 89 55 c0 4c 89 ff e8 7a 6a ae RSP: 0018:ffffc9000b2c7c98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000000041ed RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b2c7cd8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82baac10 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007be9f22cf740(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000030 CR3: 0000000134b08000 CR4: 00000000000006f0 Call Trace: <TASK> ? show_regs+0x6d/0x80 ? __die+0x24/0x80 ? page_fault_oops+0x99/0x1b0 ? kernelmode_fixup_or_oops+0xb2/0x140 ? __bad_area_nosemaphore+0x1a5/0x2c0 ? find_vma+0x34/0x60 ? bad_area_nosemaphore+0x16/0x30 ? do_user_addr_fault+0x2a2/0x6b0 ? exc_page_fault+0x83/0x1b0 ? asm_exc_page_fault+0x27/0x30 ? aafs_create.constprop.0+0x7f/0x130 ? aafs_create.constprop.0+0x51/0x130 __aafs_profile_mkdir+0x3d6/0x480 aa_replace_profiles+0x83f/0x1270 policy_update+0xe3/0x180 profile_load+0xbc/0x150 ? rw_verify_area+0x47/0x140 vfs_write+0x100/0x480 ? __x64_sys_openat+0x55/0xa0 ? syscall_exit_to_user_mode+0x86/0x260 ksys_write+0x73/0x100 __x64_sys_write+0x19/0x30 x64_sys_call+0x7e/0x25c0 do_syscall_64+0x7f/0x180 entry_SYSCALL_64_after_hwframe+0x78/0x80 RIP: 0033:0x7be9f211c574 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89 RSP: 002b:00007ffd26f2b8c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00005d504415e200 RCX: 00007be9f211c574 RDX: 0000000000001fc1 RSI: 00005d504418bc80 RDI: 0000000000000004 RBP: 0000000000001fc1 R08: 0000000000001fc1 R09: 0000000080000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00005d504418bc80 R13: 0000000000000004 R14: 00007ffd26f2b9b0 R15: 00007ffd26f2ba30 </TASK> Modules linked in: snd_seq_dummy snd_hrtimer qrtr snd_hda_codec_generic snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device i2c_i801 snd_timer i2c_smbus qxl snd soundcore drm_ttm_helper lpc_ich ttm joydev input_leds serio_raw mac_hid binfmt_misc msr parport_pc ppdev lp parport efi_pstore nfnetlink dmi_sysfs qemu_fw_cfg ip_tables x_tables autofs4 hid_generic usbhid hid ahci libahci psmouse virtio_rng xhci_pci xhci_pci_renesas CR2: 0000000000000030 ---[ end trace 0000000000000000 ]--- RIP: 0010:aafs_create.constprop.0+0x7f/0x130 Code: 4c 63 e0 48 83 c4 18 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 45 31 d2 c3 cc cc cc cc <4d> 8b 55 30 4d 8d ba a0 00 00 00 4c 89 55 c0 4c 89 ff e8 7a 6a ae RSP: 0018:ffffc9000b2c7c98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000000041ed RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b2c7cd8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82baac10 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007be9f22cf740(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000030 CR3: 0000000134b08000 CR4: 00000000000006f0 Signed-off-by: Leesoo Ahn <[email protected]> Signed-off-by: John Johansen <[email protected]>

scx_ops_bypass() can currently race on the ops enable / disable path as follows: 1. scx_ops_bypass(true) called on enable path, bypass depth is set to 1 2. An op on the init path exits, which schedules scx_ops_disable_workfn() 3. scx_ops_bypass(false) is called on the disable path, and bypass depth is decremented to 0 4. kthread is scheduled to execute scx_ops_disable_workfn() 5. scx_ops_bypass(true) called, bypass depth set to 1 6. scx_ops_bypass() races when iterating over CPUs While it's not safe to take any blocking locks on the bypass path, it is safe to take a raw spinlock which cannot be preempted. This patch therefore updates scx_ops_bypass() to use a raw spinlock to synchronize, and changes scx_ops_bypass_depth to be a regular int. Without this change, we observe the following warnings when running the 'exit' sched_ext selftest (sometimes requires a couple of runs): .[root@virtme-ng sched_ext]# ./runner -t exit ===== START ===== TEST: exit ... [ 14.935078] WARNING: CPU: 2 PID: 360 at kernel/sched/ext.c:4332 scx_ops_bypass+0x1ca/0x280 [ 14.935126] Modules linked in: [ 14.935150] CPU: 2 UID: 0 PID: 360 Comm: sched_ext_ops_h Not tainted 6.11.0-virtme #24 [ 14.935192] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 [ 14.935242] Sched_ext: exit (enabling+all) [ 14.935244] RIP: 0010:scx_ops_bypass+0x1ca/0x280 [ 14.935300] Code: ff ff ff e8 48 96 10 00 fb e9 08 ff ff ff c6 05 7b 34 e8 01 01 90 48 c7 c7 89 86 88 87 e8 be 1d f8 ff 90 0f 0b 90 90 eb 95 90 <0f> 0b 90 41 8b 84 24 24 0a 00 00 eb 97 90 0f 0b 90 41 8b 84 24 24 [ 14.935394] RSP: 0018:ffffb706c0957ce0 EFLAGS: 00010002 [ 14.935424] RAX: 0000000000000009 RBX: 0000000000000001 RCX: 00000000e3fb8b2a [ 14.935465] RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff88a4c080 [ 14.935512] RBP: 0000000000009b56 R08: 0000000000000004 R09: 00000003f12e520a [ 14.935555] R10: ffffffff863a9795 R11: 0000000000000000 R12: ffff8fc5fec31300 [ 14.935598] R13: ffff8fc5fec31318 R14: 0000000000000286 R15: 0000000000000018 [ 14.935642] FS: 0000000000000000(0000) GS:ffff8fc5fe680000(0000) knlGS:0000000000000000 [ 14.935684] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 14.935721] CR2: 0000557d92890b88 CR3: 000000002464a000 CR4: 0000000000750ef0 [ 14.935765] PKRU: 55555554 [ 14.935782] Call Trace: [ 14.935802] <TASK> [ 14.935823] ? __warn+0xce/0x220 [ 14.935850] ? scx_ops_bypass+0x1ca/0x280 [ 14.935881] ? report_bug+0xc1/0x160 [ 14.935909] ? handle_bug+0x61/0x90 [ 14.935934] ? exc_invalid_op+0x1a/0x50 [ 14.935959] ? asm_exc_invalid_op+0x1a/0x20 [ 14.935984] ? raw_spin_rq_lock_nested+0x15/0x30 [ 14.936019] ? scx_ops_bypass+0x1ca/0x280 [ 14.936046] ? srso_alias_return_thunk+0x5/0xfbef5 [ 14.936081] ? __pfx_scx_ops_disable_workfn+0x10/0x10 [ 14.936111] scx_ops_disable_workfn+0x146/0xac0 [ 14.936142] ? finish_task_switch+0xa9/0x2c0 [ 14.936172] ? srso_alias_return_thunk+0x5/0xfbef5 [ 14.936211] ? __pfx_scx_ops_disable_workfn+0x10/0x10 [ 14.936244] kthread_worker_fn+0x101/0x2c0 [ 14.936268] ? __pfx_kthread_worker_fn+0x10/0x10 [ 14.936299] kthread+0xec/0x110 [ 14.936327] ? __pfx_kthread+0x10/0x10 [ 14.936351] ret_from_fork+0x37/0x50 [ 14.936374] ? __pfx_kthread+0x10/0x10 [ 14.936400] ret_from_fork_asm+0x1a/0x30 [ 14.936427] </TASK> [ 14.936443] irq event stamp: 21002 [ 14.936467] hardirqs last enabled at (21001): [<ffffffff863aa35f>] resched_cpu+0x9f/0xd0 [ 14.936521] hardirqs last disabled at (21002): [<ffffffff863dd0ba>] scx_ops_bypass+0x11a/0x280 [ 14.936571] softirqs last enabled at (20642): [<ffffffff863683d7>] __irq_exit_rcu+0x67/0xd0 [ 14.936622] softirqs last disabled at (20637): [<ffffffff863683d7>] __irq_exit_rcu+0x67/0xd0 [ 14.936672] ---[ end trace 0000000000000000 ]--- [ 14.953282] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) [ 14.953352] ------------[ cut here ]------------ [ 14.953383] WARNING: CPU: 2 PID: 360 at kernel/sched/ext.c:4335 scx_ops_bypass+0x1d8/0x280 [ 14.953428] Modules linked in: [ 14.953453] CPU: 2 UID: 0 PID: 360 Comm: sched_ext_ops_h Tainted: G W 6.11.0-virtme #24 [ 14.953505] Tainted: [W]=WARN [ 14.953527] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 [ 14.953574] RIP: 0010:scx_ops_bypass+0x1d8/0x280 [ 14.953603] Code: c6 05 7b 34 e8 01 01 90 48 c7 c7 89 86 88 87 e8 be 1d f8 ff 90 0f 0b 90 90 eb 95 90 0f 0b 90 41 8b 84 24 24 0a 00 00 eb 97 90 <0f> 0b 90 41 8b 84 24 24 0a 00 00 eb 92 f3 0f 1e fa 49 8d 84 24 f0 [ 14.953693] RSP: 0018:ffffb706c0957ce0 EFLAGS: 00010046 [ 14.953722] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000001 [ 14.953763] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8fc5fec31318 [ 14.953804] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 [ 14.953845] R10: ffffffff863a9795 R11: 0000000000000000 R12: ffff8fc5fec31300 [ 14.953888] R13: ffff8fc5fec31318 R14: 0000000000000286 R15: 0000000000000018 [ 14.953934] FS: 0000000000000000(0000) GS:ffff8fc5fe680000(0000) knlGS:0000000000000000 [ 14.953974] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 14.954009] CR2: 0000557d92890b88 CR3: 000000002464a000 CR4: 0000000000750ef0 [ 14.954052] PKRU: 55555554 [ 14.954068] Call Trace: [ 14.954085] <TASK> [ 14.954102] ? __warn+0xce/0x220 [ 14.954126] ? scx_ops_bypass+0x1d8/0x280 [ 14.954150] ? report_bug+0xc1/0x160 [ 14.954178] ? handle_bug+0x61/0x90 [ 14.954203] ? exc_invalid_op+0x1a/0x50 [ 14.954226] ? asm_exc_invalid_op+0x1a/0x20 [ 14.954250] ? raw_spin_rq_lock_nested+0x15/0x30 [ 14.954285] ? scx_ops_bypass+0x1d8/0x280 [ 14.954311] ? __mutex_unlock_slowpath+0x3a/0x260 [ 14.954343] scx_ops_disable_workfn+0xa3e/0xac0 [ 14.954381] ? __pfx_scx_ops_disable_workfn+0x10/0x10 [ 14.954413] kthread_worker_fn+0x101/0x2c0 [ 14.954442] ? __pfx_kthread_worker_fn+0x10/0x10 [ 14.954479] kthread+0xec/0x110 [ 14.954507] ? __pfx_kthread+0x10/0x10 [ 14.954530] ret_from_fork+0x37/0x50 [ 14.954553] ? __pfx_kthread+0x10/0x10 [ 14.954576] ret_from_fork_asm+0x1a/0x30 [ 14.954603] </TASK> [ 14.954621] irq event stamp: 21002 [ 14.954644] hardirqs last enabled at (21001): [<ffffffff863aa35f>] resched_cpu+0x9f/0xd0 [ 14.954686] hardirqs last disabled at (21002): [<ffffffff863dd0ba>] scx_ops_bypass+0x11a/0x280 [ 14.954735] softirqs last enabled at (20642): [<ffffffff863683d7>] __irq_exit_rcu+0x67/0xd0 [ 14.954782] softirqs last disabled at (20637): [<ffffffff863683d7>] __irq_exit_rcu+0x67/0xd0 [ 14.954829] ---[ end trace 0000000000000000 ]--- [ 15.022283] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) [ 15.092282] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) [ 15.149282] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) ok 1 exit # ===== END ===== And with it, the test passes without issue after 1000s of runs: .[root@virtme-ng sched_ext]# ./runner -t exit ===== START ===== TEST: exit DESCRIPTION: Verify we can cleanly exit a scheduler in multiple places OUTPUT: [ 7.412856] sched_ext: BPF scheduler "exit" enabled [ 7.427924] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) [ 7.466677] sched_ext: BPF scheduler "exit" enabled [ 7.475923] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) [ 7.512803] sched_ext: BPF scheduler "exit" enabled [ 7.532924] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) [ 7.586809] sched_ext: BPF scheduler "exit" enabled [ 7.595926] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) [ 7.661923] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) [ 7.723923] sched_ext: BPF scheduler "exit" disabled (unregistered from BPF) ok 1 exit # ===== END ===== ============================= RESULTS: PASSED: 1 SKIPPED: 0 FAILED: 0 Fixes: f0e1a06 ("sched_ext: Implement BPF extensible scheduler class") Signed-off-by: David Vernet <[email protected]> Signed-off-by: Tejun Heo <[email protected]>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) #23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) #24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]>

pabeni added the enhancement label Jun 10, 2020

matttbe moved this to To do in MPTCP Upstream: Future Feb 22, 2023

matttbe added this to MPTCP Upstream: Future Feb 22, 2023

matttbe moved this from To do to Needs triage in MPTCP Upstream: Future Apr 11, 2024

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Revisit layout of struct mptcp_subflow_context #24

Revisit layout of struct mptcp_subflow_context #24

cpaasch commented May 13, 2020 •

edited by matttbe

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Revisit layout of struct mptcp_subflow_context #24

Revisit layout of struct mptcp_subflow_context #24

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cpaasch commented May 13, 2020 • edited by matttbe Loading

cpaasch commented May 13, 2020 •

edited by matttbe

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