Why not add hfence.vvma after modify vsatp? #32
Comments
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The VSATP is the Guest/VM SATP CSR. It is programmed by the Guest/VM OS. The hypervisor only saves and restores VSATP at appropriate points. The HW TLBs will be tagged with both HGATP.VMID and VSATP.ASID so we don't need to flush TLB after switching VSATP or HGATP. We only flush TLB if HW does not implement VMID bits. Regards, |
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Thanks for the information. But I still have one question. If the host only have one core, and run the Guest OS with two core argument, Is it possible that the two cores are configured with different satp? If yes, when kvm switch context, the VMID and ASID are the same, Does still need |
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@avpatel Do you have any idea about this? Is the current code not supporting vcpus greater than the number of hardware cpus? Or it will be supported in the future? |
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The current code does support number of VCPUs greater than host CPUs. It's the KVMTOOL which print a warning when user exceed host CPUs because of performance impact. Regards, |
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OK, I encountered one issue as below. Could you help me? |
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The VSATP.ASID programming is done by Guest OS for both VCPU0 and VCPU1 but both these VCPUs will have same HGATP.VMID because they are part of same Guest/VM Now, if you are seeing mapping issue inside Guest/VM then it means your Guest OS is assigning same ASID to both VCPUs. The KVM RISC-V approch of handling HGATP.VMID and VSATP.ASID is same as other architectures. I doubt there is any issue in KVM RISC-V. Regards, |
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Does my below understanding correct?
Anyway, this is supposed to be a software problem, not a hardware problem, correct? |
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Yes, your understanding is correct. I am closing this issue since there is no activity. |
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Rafael reports that on a system with LX2160A and Marvell DSA switches, if a reboot occurs while the DSA master (dpaa2-eth) is up, the following panic can be seen: systemd-shutdown[1]: Rebooting. Unable to handle kernel paging request at virtual address 00a0000800000041 [00a0000800000041] address between user and kernel address ranges Internal error: Oops: 96000004 [#1] PREEMPT SMP CPU: 6 PID: 1 Comm: systemd-shutdow Not tainted 5.16.5-00042-g8f5585009b24 #32 pc : dsa_slave_netdevice_event+0x130/0x3e4 lr : raw_notifier_call_chain+0x50/0x6c Call trace: dsa_slave_netdevice_event+0x130/0x3e4 raw_notifier_call_chain+0x50/0x6c call_netdevice_notifiers_info+0x54/0xa0 __dev_close_many+0x50/0x130 dev_close_many+0x84/0x120 unregister_netdevice_many+0x130/0x710 unregister_netdevice_queue+0x8c/0xd0 unregister_netdev+0x20/0x30 dpaa2_eth_remove+0x68/0x190 fsl_mc_driver_remove+0x20/0x5c __device_release_driver+0x21c/0x220 device_release_driver_internal+0xac/0xb0 device_links_unbind_consumers+0xd4/0x100 __device_release_driver+0x94/0x220 device_release_driver+0x28/0x40 bus_remove_device+0x118/0x124 device_del+0x174/0x420 fsl_mc_device_remove+0x24/0x40 __fsl_mc_device_remove+0xc/0x20 device_for_each_child+0x58/0xa0 dprc_remove+0x90/0xb0 fsl_mc_driver_remove+0x20/0x5c __device_release_driver+0x21c/0x220 device_release_driver+0x28/0x40 bus_remove_device+0x118/0x124 device_del+0x174/0x420 fsl_mc_bus_remove+0x80/0x100 fsl_mc_bus_shutdown+0xc/0x1c platform_shutdown+0x20/0x30 device_shutdown+0x154/0x330 __do_sys_reboot+0x1cc/0x250 __arm64_sys_reboot+0x20/0x30 invoke_syscall.constprop.0+0x4c/0xe0 do_el0_svc+0x4c/0x150 el0_svc+0x24/0xb0 el0t_64_sync_handler+0xa8/0xb0 el0t_64_sync+0x178/0x17c It can be seen from the stack trace that the problem is that the deregistration of the master causes a dev_close(), which gets notified as NETDEV_GOING_DOWN to dsa_slave_netdevice_event(). But dsa_switch_shutdown() has already run, and this has unregistered the DSA slave interfaces, and yet, the NETDEV_GOING_DOWN handler attempts to call dev_close_many() on those slave interfaces, leading to the problem. The previous attempt to avoid the NETDEV_GOING_DOWN on the master after dsa_switch_shutdown() was called seems improper. Unregistering the slave interfaces is unnecessary and unhelpful. Instead, after the slaves have stopped being uppers of the DSA master, we can now reset to NULL the master->dsa_ptr pointer, which will make DSA start ignoring all future notifier events on the master. Fixes: 0650bf5 ("net: dsa: be compatible with masters which unregister on shutdown") Reported-by: Rafael Richter <[email protected]> Signed-off-by: Vladimir Oltean <[email protected]> Signed-off-by: David S. Miller <[email protected]>
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This commit adds python script to parse CoreSight tracing event and
print out source line and disassembly, it generates readable program
execution flow for easier humans inspecting.
The script receives CoreSight tracing packet with below format:
+------------+------------+------------+
packet(n): | addr | ip | cpu |
+------------+------------+------------+
packet(n+1): | addr | ip | cpu |
+------------+------------+------------+
packet::addr presents the start address of the coming branch sample, and
packet::ip is the last address of the branch smple. Therefore, a code
section between branches starts from packet(n)::addr and it stops at
packet(n+1)::ip. As results we combines the two continuous packets to
generate the address range for instructions:
[ sample(n)::addr .. sample(n+1)::ip ]
The script supports both objdump or llvm-objdump for disassembly with
specifying option '-d'. If doesn't specify option '-d', the script
simply outputs source lines and symbols.
Below shows usages with llvm-objdump or objdump to output disassembly.
# perf script -s scripts/python/arm-cs-trace-disasm.py -- -d llvm-objdump-11 -k ./vmlinux
ARM CoreSight Trace Data Assembler Dump
ffff800008eb3198 <etm4_enable_hw>:
ffff800008eb3310: c0 38 00 35 cbnz w0, 0xffff800008eb3a28 <etm4_enable_hw+0x890>
ffff800008eb3314: 9f 3f 03 d5 dsb sy
ffff800008eb3318: df 3f 03 d5 isb
ffff800008eb331c: f5 5b 42 a9 ldp x21, x22, [sp, #32]
ffff800008eb3320: fb 73 45 a9 ldp x27, x28, [sp, #80]
ffff800008eb3324: e0 82 40 39 ldrb w0, [x23, #32]
ffff800008eb3328: 60 00 00 34 cbz w0, 0xffff800008eb3334 <etm4_enable_hw+0x19c>
ffff800008eb332c: e0 03 19 aa mov x0, x25
ffff800008eb3330: 8c fe ff 97 bl 0xffff800008eb2d60 <etm4_cs_lock.isra.0.part.0>
main 6728/6728 [0004] 0.000000000 etm4_enable_hw+0x198 [kernel.kallsyms]
ffff800008eb2d60 <etm4_cs_lock.isra.0.part.0>:
ffff800008eb2d60: 1f 20 03 d5 nop
ffff800008eb2d64: 1f 20 03 d5 nop
ffff800008eb2d68: 3f 23 03 d5 hint #25
ffff800008eb2d6c: 00 00 40 f9 ldr x0, [x0]
ffff800008eb2d70: 9f 3f 03 d5 dsb sy
ffff800008eb2d74: 00 c0 3e 91 add x0, x0, #4016
ffff800008eb2d78: 1f 00 00 b9 str wzr, [x0]
ffff800008eb2d7c: bf 23 03 d5 hint #29
ffff800008eb2d80: c0 03 5f d6 ret
main 6728/6728 [0004] 0.000000000 etm4_cs_lock.isra.0.part.0+0x20
# perf script -s scripts/python/arm-cs-trace-disasm.py -- -d objdump -k ./vmlinux
ARM CoreSight Trace Data Assembler Dump
ffff800008eb3310 <etm4_enable_hw+0x178>:
ffff800008eb3310: 350038c0 cbnz w0, ffff800008eb3a28 <etm4_enable_hw+0x890>
ffff800008eb3314: d5033f9f dsb sy
ffff800008eb3318: d5033fdf isb
ffff800008eb331c: a9425bf5 ldp x21, x22, [sp, #32]
ffff800008eb3320: a94573fb ldp x27, x28, [sp, #80]
ffff800008eb3324: 394082e0 ldrb w0, [x23, #32]
ffff800008eb3328: 34000060 cbz w0, ffff800008eb3334 <etm4_enable_hw+0x19c>
ffff800008eb332c: aa1903e0 mov x0, x25
ffff800008eb3330: 97fffe8c bl ffff800008eb2d60 <etm4_cs_lock.isra.0.part.0>
main 6728/6728 [0004] 0.000000000 etm4_enable_hw+0x198 [kernel.kallsyms]
ffff800008eb2d60 <etm4_cs_lock.isra.0.part.0>:
ffff800008eb2d60: d503201f nop
ffff800008eb2d64: d503201f nop
ffff800008eb2d68: d503233f paciasp
ffff800008eb2d6c: f9400000 ldr x0, [x0]
ffff800008eb2d70: d5033f9f dsb sy
ffff800008eb2d74: 913ec000 add x0, x0, #0xfb0
ffff800008eb2d78: b900001f str wzr, [x0]
ffff800008eb2d7c: d50323bf autiasp
ffff800008eb2d80: d65f03c0 ret
main 6728/6728 [0004] 0.000000000 etm4_cs_lock.isra.0.part.0+0x20
Signed-off-by: Leo Yan <[email protected]>
Co-authored-by: Al Grant <[email protected]>
Co-authored-by: Mathieu Poirier <[email protected]>
Co-authored-by: Tor Jeremiassen <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Eelco Chaudron <[email protected]>
Cc: German Gomez <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephen Brennan <[email protected]>
Cc: Tanmay Jagdale <[email protected]>
Cc: [email protected]
Cc: zengshun . wu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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By keep sending L2CAP_CONF_REQ packets, chan->num_conf_rsp increases
multiple times and eventually it will wrap around the maximum number
(i.e., 255).
This patch prevents this by adding a boundary check with
L2CAP_MAX_CONF_RSP
Btmon log:
Bluetooth monitor ver 5.64
= Note: Linux version 6.1.0-rc2 (x86_64) 0.264594
= Note: Bluetooth subsystem version 2.22 0.264636
@ MGMT Open: btmon (privileged) version 1.22 {0x0001} 0.272191
= New Index: 00:00:00:00:00:00 (Primary,Virtual,hci0) [hci0] 13.877604
@ RAW Open: 9496 (privileged) version 2.22 {0x0002} 13.890741
= Open Index: 00:00:00:00:00:00 [hci0] 13.900426
(...)
> ACL Data RX: Handle 200 flags 0x00 dlen 1033 #32 [hci0] 14.273106
invalid packet size (12 != 1033)
08 00 01 00 02 01 04 00 01 10 ff ff ............
> ACL Data RX: Handle 200 flags 0x00 dlen 1547 #33 [hci0] 14.273561
invalid packet size (14 != 1547)
0a 00 01 00 04 01 06 00 40 00 00 00 00 00 ........@.....
> ACL Data RX: Handle 200 flags 0x00 dlen 2061 #34 [hci0] 14.274390
invalid packet size (16 != 2061)
0c 00 01 00 04 01 08 00 40 00 00 00 00 00 00 04 ........@.......
> ACL Data RX: Handle 200 flags 0x00 dlen 2061 #35 [hci0] 14.274932
invalid packet size (16 != 2061)
0c 00 01 00 04 01 08 00 40 00 00 00 07 00 03 00 ........@.......
= bluetoothd: Bluetooth daemon 5.43 14.401828
> ACL Data RX: Handle 200 flags 0x00 dlen 1033 #36 [hci0] 14.275753
invalid packet size (12 != 1033)
08 00 01 00 04 01 04 00 40 00 00 00 ........@...
Signed-off-by: Sungwoo Kim <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>
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The conclusion "j1939_session_deactivate() should be called with a
session ref-count of at least 2" is incorrect. In some concurrent
scenarios, j1939_session_deactivate can be called with the session
ref-count less than 2. But there is not any problem because it
will check the session active state before session putting in
j1939_session_deactivate_locked().
Here is the concurrent scenario of the problem reported by syzbot
and my reproduction log.
cpu0 cpu1
j1939_xtp_rx_eoma
j1939_xtp_rx_abort_one
j1939_session_get_by_addr [kref == 2]
j1939_session_get_by_addr [kref == 3]
j1939_session_deactivate [kref == 2]
j1939_session_put [kref == 1]
j1939_session_completed
j1939_session_deactivate
WARN_ON_ONCE(kref < 2)
=====================================================
WARNING: CPU: 1 PID: 21 at net/can/j1939/transport.c:1088 j1939_session_deactivate+0x5f/0x70
CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 5.14.0-rc7+ #32
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014
RIP: 0010:j1939_session_deactivate+0x5f/0x70
Call Trace:
j1939_session_deactivate_activate_next+0x11/0x28
j1939_xtp_rx_eoma+0x12a/0x180
j1939_tp_recv+0x4a2/0x510
j1939_can_recv+0x226/0x380
can_rcv_filter+0xf8/0x220
can_receive+0x102/0x220
? process_backlog+0xf0/0x2c0
can_rcv+0x53/0xf0
__netif_receive_skb_one_core+0x67/0x90
? process_backlog+0x97/0x2c0
__netif_receive_skb+0x22/0x80
Fixes: 0c71437 ("can: j1939: j1939_session_deactivate(): clarify lifetime of session object")
Reported-by: [email protected]
Signed-off-by: Ziyang Xuan <[email protected]>
Acked-by: Oleksij Rempel <[email protected]>
Link: https://lore.kernel.org/all/[email protected]
Signed-off-by: Marc Kleine-Budde <[email protected]>
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------------[ cut here ]------------ memcpy: detected field-spanning write (size 56) of single field "eseg->inline_hdr.start" at /var/lib/dkms/mlnx-ofed-kernel/5.8/build/drivers/infiniband/hw/mlx5/wr.c:131 (size 2) WARNING: CPU: 0 PID: 293779 at /var/lib/dkms/mlnx-ofed-kernel/5.8/build/drivers/infiniband/hw/mlx5/wr.c:131 mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] Modules linked in: 8021q garp mrp stp llc rdma_ucm(OE) rdma_cm(OE) iw_cm(OE) ib_ipoib(OE) ib_cm(OE) ib_umad(OE) mlx5_ib(OE) ib_uverbs(OE) ib_core(OE) mlx5_core(OE) pci_hyperv_intf mlxdevm(OE) mlx_compat(OE) tls mlxfw(OE) psample nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables libcrc32c nfnetlink mst_pciconf(OE) knem(OE) vfio_pci vfio_pci_core vfio_iommu_type1 vfio iommufd irqbypass cuse nfsv3 nfs fscache netfs xfrm_user xfrm_algo ipmi_devintf ipmi_msghandler binfmt_misc crct10dif_pclmul crc32_pclmul polyval_clmulni polyval_generic ghash_clmulni_intel sha512_ssse3 snd_pcsp aesni_intel crypto_simd cryptd snd_pcm snd_timer joydev snd soundcore input_leds serio_raw evbug nfsd auth_rpcgss nfs_acl lockd grace sch_fq_codel sunrpc drm efi_pstore ip_tables x_tables autofs4 psmouse virtio_net net_failover failover floppy [last unloaded: mlx_compat(OE)] CPU: 0 PID: 293779 Comm: ssh Tainted: G OE 6.2.0-32-generic #32~22.04.1-Ubuntu Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 RIP: 0010:mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] Code: 0c 01 00 a8 01 75 25 48 8b 75 a0 b9 02 00 00 00 48 c7 c2 10 5b fd c0 48 c7 c7 80 5b fd c0 c6 05 57 0c 03 00 01 e8 95 4d 93 da <0f> 0b 44 8b 4d b0 4c 8b 45 c8 48 8b 4d c0 e9 49 fb ff ff 41 0f b7 RSP: 0018:ffffb5b48478b570 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffb5b48478b628 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffb5b48478b5e8 R13: ffff963a3c609b5e R14: ffff9639c3fbd800 R15: ffffb5b480475a80 FS: 00007fc03b444c80(0000) GS:ffff963a3dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556f46bdf000 CR3: 0000000006ac6003 CR4: 00000000003706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? show_regs+0x72/0x90 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] ? __warn+0x8d/0x160 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] ? report_bug+0x1bb/0x1d0 ? handle_bug+0x46/0x90 ? exc_invalid_op+0x19/0x80 ? asm_exc_invalid_op+0x1b/0x20 ? mlx5_ib_post_send+0x191b/0x1a60 [mlx5_ib] mlx5_ib_post_send_nodrain+0xb/0x20 [mlx5_ib] ipoib_send+0x2ec/0x770 [ib_ipoib] ipoib_start_xmit+0x5a0/0x770 [ib_ipoib] dev_hard_start_xmit+0x8e/0x1e0 ? validate_xmit_skb_list+0x4d/0x80 sch_direct_xmit+0x116/0x3a0 __dev_xmit_skb+0x1fd/0x580 __dev_queue_xmit+0x284/0x6b0 ? _raw_spin_unlock_irq+0xe/0x50 ? __flush_work.isra.0+0x20d/0x370 ? push_pseudo_header+0x17/0x40 [ib_ipoib] neigh_connected_output+0xcd/0x110 ip_finish_output2+0x179/0x480 ? __smp_call_single_queue+0x61/0xa0 __ip_finish_output+0xc3/0x190 ip_finish_output+0x2e/0xf0 ip_output+0x78/0x110 ? __pfx_ip_finish_output+0x10/0x10 ip_local_out+0x64/0x70 __ip_queue_xmit+0x18a/0x460 ip_queue_xmit+0x15/0x30 __tcp_transmit_skb+0x914/0x9c0 tcp_write_xmit+0x334/0x8d0 tcp_push_one+0x3c/0x60 tcp_sendmsg_locked+0x2e1/0xac0 tcp_sendmsg+0x2d/0x50 inet_sendmsg+0x43/0x90 sock_sendmsg+0x68/0x80 sock_write_iter+0x93/0x100 vfs_write+0x326/0x3c0 ksys_write+0xbd/0xf0 ? do_syscall_64+0x69/0x90 __x64_sys_write+0x19/0x30 do_syscall_64+0x59/0x90 ? do_user_addr_fault+0x1d0/0x640 ? exit_to_user_mode_prepare+0x3b/0xd0 ? irqentry_exit_to_user_mode+0x9/0x20 ? irqentry_exit+0x43/0x50 ? exc_page_fault+0x92/0x1b0 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7fc03ad14a37 Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007ffdf8697fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000008024 RCX: 00007fc03ad14a37 RDX: 0000000000008024 RSI: 0000556f46bd8270 RDI: 0000000000000003 RBP: 0000556f46bb1800 R08: 0000000000007fe3 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 0000556f46bc66b0 R14: 000000000000000a R15: 0000556f46bb2f50 </TASK> ---[ end trace 0000000000000000 ]--- Link: https://lore.kernel.org/r/8228ad34bd1a25047586270f7b1fb4ddcd046282.1706433934.git.leon@kernel.org Signed-off-by: Leon Romanovsky <[email protected]>
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With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To
thwart invalid memory accesses, the JITs add an exception table entry
for all such accesses. But in case the src_reg + offset is a userspace
address, the BPF program might read that memory if the user has
mapped it.
Make the verifier add guard instructions around such memory accesses and
skip the load if the address falls into the userspace region.
The JITs need to implement bpf_arch_uaddress_limit() to define where
the userspace addresses end for that architecture or TASK_SIZE is taken
as default.
The implementation is as follows:
REG_AX = SRC_REG
if(offset)
REG_AX += offset;
REG_AX >>= 32;
if (REG_AX <= (uaddress_limit >> 32))
DST_REG = 0;
else
DST_REG = *(size *)(SRC_REG + offset);
Comparing just the upper 32 bits of the load address with the upper
32 bits of uaddress_limit implies that the values are being aligned down
to a 4GB boundary before comparison.
The above means that all loads with address <= uaddress_limit + 4GB are
skipped. This is acceptable because there is a large hole (much larger
than 4GB) between userspace and kernel space memory, therefore a
correctly functioning BPF program should not access this 4GB memory
above the userspace.
Let's analyze what this patch does to the following fentry program
dereferencing an untrusted pointer:
SEC("fentry/tcp_v4_connect")
int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk)
{
*(volatile long *)sk;
return 0;
}
BPF Program before | BPF Program after
------------------ | -----------------
0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0)
-----------------------------------------------------------------------
1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1
----------------------------\ \ 2: (77) r11 >>= 32
2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2
3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0)
\ 5: (05) goto pc+1
\ 6: (b7) r1 = 0
\--------------------------------------
7: (b7) r0 = 0
8: (95) exit
As you can see from above, in the best case (off=0), 5 extra instructions
are emitted.
Now, we analyze the same program after it has gone through the JITs of
ARM64 and RISC-V architectures. We follow the single load instruction
that has the untrusted pointer and see what instrumentation has been
added around it.
x86-64 JIT
==========
JIT's Instrumentation
(upstream)
---------------------
0: nopl 0x0(%rax,%rax,1)
5: xchg %ax,%ax
7: push %rbp
8: mov %rsp,%rbp
b: mov 0x0(%rdi),%rdi
---------------------------------
f: movabs $0x800000000000,%r11
19: cmp %r11,%rdi
1c: jb 0x000000000000002a
1e: mov %rdi,%r11
21: add $0x0,%r11
28: jae 0x000000000000002e
2a: xor %edi,%edi
2c: jmp 0x0000000000000032
2e: mov 0x0(%rdi),%rdi
---------------------------------
32: xor %eax,%eax
34: leave
35: ret
The x86-64 JIT already emits some instructions to protect against user
memory access. This patch doesn't make any changes for the x86-64 JIT.
ARM64 JIT
=========
No Intrumentation Verifier's Instrumentation
(upstream) (This patch)
----------------- --------------------------
0: add x9, x30, #0x0 0: add x9, x30, #0x0
4: nop 4: nop
8: paciasp 8: paciasp
c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]!
10: mov x29, sp 10: mov x29, sp
14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]!
18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]!
1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]!
20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]!
24: mov x25, sp 24: mov x25, sp
28: mov x26, #0x0 28: mov x26, #0x0
2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0
30: sub sp, sp, #0x0 30: sub sp, sp, #0x0
34: ldr x0, [x0] 34: ldr x0, [x0]
--------------------------------------------------------------------------------
38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0
-----------------------------------\\ 3c: lsr x9, x9, #32
3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl #12
40: mov sp, sp \\ 44: b.ls 0x0000000000000050
44: ldp x27, x28, [sp], #16 \\--> 48: ldr x0, [x0]
48: ldp x25, x26, [sp], #16 \ 4c: b 0x0000000000000054
4c: ldp x21, x22, [sp], #16 \ 50: mov x0, #0x0
50: ldp x19, x20, [sp], #16 \---------------------------------------
54: ldp x29, x30, [sp], #16 54: mov x7, #0x0
58: add x0, x7, #0x0 58: mov sp, sp
5c: autiasp 5c: ldp x27, x28, [sp], #16
60: ret 60: ldp x25, x26, [sp], #16
64: nop 64: ldp x21, x22, [sp], #16
68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], #16
6c: br x10 6c: ldp x29, x30, [sp], #16
70: add x0, x7, #0x0
74: autiasp
78: ret
7c: nop
80: ldr x10, 0x0000000000000088
84: br x10
There are 6 extra instructions added in ARM64 in the best case. This will
become 7 in the worst case (off != 0).
RISC-V JIT (RISCV_ISA_C Disabled)
==========
No Intrumentation Verifier's Instrumentation
(upstream) (This patch)
----------------- --------------------------
0: nop 0: nop
4: nop 4: nop
8: li a6, 33 8: li a6, 33
c: addi sp, sp, -16 c: addi sp, sp, -16
10: sd s0, 8(sp) 10: sd s0, 8(sp)
14: addi s0, sp, 16 14: addi s0, sp, 16
18: ld a0, 0(a0) 18: ld a0, 0(a0)
---------------------------------------------------------------
1c: ld a0, 0(a0) --\ 1c: mv t0, a0
--------------------------\ \ 20: srli t0, t0, 32
20: li a5, 0 \ \ 24: lui t1, 4096
24: ld s0, 8(sp) \ \ 28: sext.w t1, t1
28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12
2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0)
30: ret \ 34: j 8
\ 38: li a0, 0
\------------------------------
3c: li a5, 0
40: ld s0, 8(sp)
44: addi sp, sp, 16
48: sext.w a0, a5
4c: ret
There are 7 extra instructions added in RISC-V.
Fixes: 8008342 ("bpf, arm64: Add BPF exception tables")
Reported-by: Breno Leitao <[email protected]>
Suggested-by: Alexei Starovoitov <[email protected]>
Acked-by: Ilya Leoshkevich <[email protected]>
Signed-off-by: Puranjay Mohan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
avpatel
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KMSAN reported uninit-value access in __unix_walk_scc() [1]. In the list_for_each_entry_reverse() loop, when the vertex's index equals it's scc_index, the loop uses the variable vertex as a temporary variable that points to a vertex in scc. And when the loop is finished, the variable vertex points to the list head, in this case scc, which is a local variable on the stack (more precisely, it's not even scc and might underflow the call stack of __unix_walk_scc(): container_of(&scc, struct unix_vertex, scc_entry)). However, the variable vertex is used under the label prev_vertex. So if the edge_stack is not empty and the function jumps to the prev_vertex label, the function will access invalid data on the stack. This causes the uninit-value access issue. Fix this by introducing a new temporary variable for the loop. [1] BUG: KMSAN: uninit-value in __unix_walk_scc net/unix/garbage.c:478 [inline] BUG: KMSAN: uninit-value in unix_walk_scc net/unix/garbage.c:526 [inline] BUG: KMSAN: uninit-value in __unix_gc+0x2589/0x3c20 net/unix/garbage.c:584 __unix_walk_scc net/unix/garbage.c:478 [inline] unix_walk_scc net/unix/garbage.c:526 [inline] __unix_gc+0x2589/0x3c20 net/unix/garbage.c:584 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xade/0x1bf0 kernel/workqueue.c:3312 worker_thread+0xeb6/0x15b0 kernel/workqueue.c:3393 kthread+0x3c4/0x530 kernel/kthread.c:389 ret_from_fork+0x6e/0x90 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Uninit was stored to memory at: unix_walk_scc net/unix/garbage.c:526 [inline] __unix_gc+0x2adf/0x3c20 net/unix/garbage.c:584 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xade/0x1bf0 kernel/workqueue.c:3312 worker_thread+0xeb6/0x15b0 kernel/workqueue.c:3393 kthread+0x3c4/0x530 kernel/kthread.c:389 ret_from_fork+0x6e/0x90 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Local variable entries created at: ref_tracker_free+0x48/0xf30 lib/ref_tracker.c:222 netdev_tracker_free include/linux/netdevice.h:4058 [inline] netdev_put include/linux/netdevice.h:4075 [inline] dev_put include/linux/netdevice.h:4101 [inline] update_gid_event_work_handler+0xaa/0x1b0 drivers/infiniband/core/roce_gid_mgmt.c:813 CPU: 1 PID: 12763 Comm: kworker/u8:31 Not tainted 6.10.0-rc4-00217-g35bb670d65fc #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 Workqueue: events_unbound __unix_gc Fixes: 3484f06 ("af_unix: Detect Strongly Connected Components.") Reported-by: syzkaller <[email protected]> Signed-off-by: Shigeru Yoshida <[email protected]> Reviewed-by: Kuniyuki Iwashima <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
avpatel
pushed a commit
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KMSAN reported uninit-value access in raw_lookup() [1]. Diag for raw sockets uses the pad field in struct inet_diag_req_v2 for the underlying protocol. This field corresponds to the sdiag_raw_protocol field in struct inet_diag_req_raw. inet_diag_get_exact_compat() converts inet_diag_req to inet_diag_req_v2, but leaves the pad field uninitialized. So the issue occurs when raw_lookup() accesses the sdiag_raw_protocol field. Fix this by initializing the pad field in inet_diag_get_exact_compat(). Also, do the same fix in inet_diag_dump_compat() to avoid the similar issue in the future. [1] BUG: KMSAN: uninit-value in raw_lookup net/ipv4/raw_diag.c:49 [inline] BUG: KMSAN: uninit-value in raw_sock_get+0x657/0x800 net/ipv4/raw_diag.c:71 raw_lookup net/ipv4/raw_diag.c:49 [inline] raw_sock_get+0x657/0x800 net/ipv4/raw_diag.c:71 raw_diag_dump_one+0xa1/0x660 net/ipv4/raw_diag.c:99 inet_diag_cmd_exact+0x7d9/0x980 inet_diag_get_exact_compat net/ipv4/inet_diag.c:1404 [inline] inet_diag_rcv_msg_compat+0x469/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 netlink_rcv_skb+0x537/0x670 net/netlink/af_netlink.c:2564 sock_diag_rcv+0x35/0x40 net/core/sock_diag.c:297 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0xe74/0x1240 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x10c6/0x1260 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x332/0x3d0 net/socket.c:745 ____sys_sendmsg+0x7f0/0xb70 net/socket.c:2585 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2639 __sys_sendmsg net/socket.c:2668 [inline] __do_sys_sendmsg net/socket.c:2677 [inline] __se_sys_sendmsg net/socket.c:2675 [inline] __x64_sys_sendmsg+0x27e/0x4a0 net/socket.c:2675 x64_sys_call+0x135e/0x3ce0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was stored to memory at: raw_sock_get+0x650/0x800 net/ipv4/raw_diag.c:71 raw_diag_dump_one+0xa1/0x660 net/ipv4/raw_diag.c:99 inet_diag_cmd_exact+0x7d9/0x980 inet_diag_get_exact_compat net/ipv4/inet_diag.c:1404 [inline] inet_diag_rcv_msg_compat+0x469/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 netlink_rcv_skb+0x537/0x670 net/netlink/af_netlink.c:2564 sock_diag_rcv+0x35/0x40 net/core/sock_diag.c:297 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0xe74/0x1240 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x10c6/0x1260 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x332/0x3d0 net/socket.c:745 ____sys_sendmsg+0x7f0/0xb70 net/socket.c:2585 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2639 __sys_sendmsg net/socket.c:2668 [inline] __do_sys_sendmsg net/socket.c:2677 [inline] __se_sys_sendmsg net/socket.c:2675 [inline] __x64_sys_sendmsg+0x27e/0x4a0 net/socket.c:2675 x64_sys_call+0x135e/0x3ce0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Local variable req.i created at: inet_diag_get_exact_compat net/ipv4/inet_diag.c:1396 [inline] inet_diag_rcv_msg_compat+0x2a6/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 CPU: 1 PID: 8888 Comm: syz-executor.6 Not tainted 6.10.0-rc4-00217-g35bb670d65fc #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 Fixes: 432490f ("net: ip, diag -- Add diag interface for raw sockets") Reported-by: syzkaller <[email protected]> Signed-off-by: Shigeru Yoshida <[email protected]> Reviewed-by: Eric Dumazet <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Paolo Abeni <[email protected]>
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linux/arch/riscv/kvm/vcpu.c
Line 792 in ad56588
I only found a modification of vsatp here. If
csr->vsatpis different with CSR_VSATP, I think hfence.vma should be added after write CSR_VSATP.BTW, I can't find the modification of
csr->vsatp. Could you help to point out howcsr->vsatpwas modified?Thanks
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