Skip to content

Commit

Permalink
[dfsan] Wrap glibc 2.38 __isoc23_* functions (llvm#79958)
Browse files Browse the repository at this point in the history 
Fix llvm#79283: `test/dfsan/custom.cpp` has undefined symbol linker errors
on glibc 2.38 due to lack of wrappers for `__isoc23_strtol` and
`__isoc23_scanf` family functions.

Implement these wrappers as aliases to existing wrappers, similar to
https://reviews.llvm.org/D158943 for other sanitizers.

`strtol` in a user program, whether or not `_ISOC2X_SOURCE` is defined,
uses the C23 semantics (`strtol("0b1", 0, 0)` => 1), when
`libclang_rt.dfsan.a` is built on glibc 2.38+.
  • Loading branch information
@MaskRay
MaskRay authored Jan 30, 2024
1 parent 9b91c54 commit 6485600
Show file tree
Hide file tree
Showing 3 changed files with 59 additions and 155 deletions.
203 changes: 48 additions & 155 deletions compiler-rt/lib/dfsan/dfsan_custom.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -55,6 +55,10 @@ using namespace __dfsan;
#define DECLARE_WEAK_INTERCEPTOR_HOOK(f, ...) \
SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE void f(__VA_ARGS__);

#define WRAPPER_ALIAS(fun, real) \
SANITIZER_INTERFACE_ATTRIBUTE void __dfsw_##fun() ALIAS(__dfsw_##real); \
SANITIZER_INTERFACE_ATTRIBUTE void __dfso_##fun() ALIAS(__dfso_##real);

// Async-safe, non-reentrant spin lock.
class SignalSpinLocker {
public:
Expand Down Expand Up @@ -1197,16 +1201,20 @@ char *__dfso_strcpy(char *dest, const char *src, dfsan_label dst_label,
*ret_origin = dst_origin;
return ret;
}
}

static long int dfsan_strtol(const char *nptr, char **endptr, int base,
char **tmp_endptr) {
template <typename Fn>
static ALWAYS_INLINE auto dfsan_strtol_impl(
Fn real, const char *nptr, char **endptr, int base,
char **tmp_endptr) -> decltype(real(nullptr, nullptr, 0)) {
assert(tmp_endptr);
long int ret = strtol(nptr, tmp_endptr, base);
auto ret = real(nptr, tmp_endptr, base);
if (endptr)
*endptr = *tmp_endptr;
return ret;
}

extern "C" {
static void dfsan_strtolong_label(const char *nptr, const char *tmp_endptr,
dfsan_label base_label,
dfsan_label *ret_label) {
Expand Down Expand Up @@ -1236,30 +1244,6 @@ static void dfsan_strtolong_origin(const char *nptr, const char *tmp_endptr,
}
}

SANITIZER_INTERFACE_ATTRIBUTE
long int __dfsw_strtol(const char *nptr, char **endptr, int base,
dfsan_label nptr_label, dfsan_label endptr_label,
dfsan_label base_label, dfsan_label *ret_label) {
char *tmp_endptr;
long int ret = dfsan_strtol(nptr, endptr, base, &tmp_endptr);
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label);
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
long int __dfso_strtol(const char *nptr, char **endptr, int base,
dfsan_label nptr_label, dfsan_label endptr_label,
dfsan_label base_label, dfsan_label *ret_label,
dfsan_origin nptr_origin, dfsan_origin endptr_origin,
dfsan_origin base_origin, dfsan_origin *ret_origin) {
char *tmp_endptr;
long int ret = dfsan_strtol(nptr, endptr, base, &tmp_endptr);
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label);
dfsan_strtolong_origin(nptr, tmp_endptr, base_label, ret_label, base_origin,
ret_origin);
return ret;
}

static double dfsan_strtod(const char *nptr, char **endptr, char **tmp_endptr) {
assert(tmp_endptr);
double ret = strtod(nptr, tmp_endptr);
Expand Down Expand Up @@ -1307,108 +1291,40 @@ double __dfso_strtod(const char *nptr, char **endptr, dfsan_label nptr_label,
return ret;
}

static long long int dfsan_strtoll(const char *nptr, char **endptr, int base,
char **tmp_endptr) {
assert(tmp_endptr);
long long int ret = strtoll(nptr, tmp_endptr, base);
if (endptr)
*endptr = *tmp_endptr;
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
long long int __dfsw_strtoll(const char *nptr, char **endptr, int base,
dfsan_label nptr_label, dfsan_label endptr_label,
dfsan_label base_label, dfsan_label *ret_label) {
char *tmp_endptr;
long long int ret = dfsan_strtoll(nptr, endptr, base, &tmp_endptr);
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label);
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
long long int __dfso_strtoll(const char *nptr, char **endptr, int base,
dfsan_label nptr_label, dfsan_label endptr_label,
dfsan_label base_label, dfsan_label *ret_label,
dfsan_origin nptr_origin,
dfsan_origin endptr_origin,
dfsan_origin base_origin,
dfsan_origin *ret_origin) {
char *tmp_endptr;
long long int ret = dfsan_strtoll(nptr, endptr, base, &tmp_endptr);
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label);
dfsan_strtolong_origin(nptr, tmp_endptr, base_label, ret_label, base_origin,
ret_origin);
return ret;
}

static unsigned long int dfsan_strtoul(const char *nptr, char **endptr,
int base, char **tmp_endptr) {
assert(tmp_endptr);
unsigned long int ret = strtoul(nptr, tmp_endptr, base);
if (endptr)
*endptr = *tmp_endptr;
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
unsigned long int __dfsw_strtoul(const char *nptr, char **endptr, int base,
dfsan_label nptr_label, dfsan_label endptr_label,
dfsan_label base_label, dfsan_label *ret_label) {
char *tmp_endptr;
unsigned long int ret = dfsan_strtoul(nptr, endptr, base, &tmp_endptr);
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label);
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
unsigned long int __dfso_strtoul(
const char *nptr, char **endptr, int base, dfsan_label nptr_label,
dfsan_label endptr_label, dfsan_label base_label, dfsan_label *ret_label,
dfsan_origin nptr_origin, dfsan_origin endptr_origin,
dfsan_origin base_origin, dfsan_origin *ret_origin) {
char *tmp_endptr;
unsigned long int ret = dfsan_strtoul(nptr, endptr, base, &tmp_endptr);
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label);
dfsan_strtolong_origin(nptr, tmp_endptr, base_label, ret_label, base_origin,
ret_origin);
return ret;
}

static long long unsigned int dfsan_strtoull(const char *nptr, char **endptr,
int base, char **tmp_endptr) {
assert(tmp_endptr);
long long unsigned int ret = strtoull(nptr, tmp_endptr, base);
if (endptr)
*endptr = *tmp_endptr;
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
long long unsigned int __dfsw_strtoull(const char *nptr, char **endptr,
int base, dfsan_label nptr_label,
dfsan_label endptr_label,
dfsan_label base_label,
dfsan_label *ret_label) {
char *tmp_endptr;
long long unsigned int ret = dfsan_strtoull(nptr, endptr, base, &tmp_endptr);
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label);
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
long long unsigned int __dfso_strtoull(
const char *nptr, char **endptr, int base, dfsan_label nptr_label,
dfsan_label endptr_label, dfsan_label base_label, dfsan_label *ret_label,
dfsan_origin nptr_origin, dfsan_origin endptr_origin,
dfsan_origin base_origin, dfsan_origin *ret_origin) {
char *tmp_endptr;
long long unsigned int ret = dfsan_strtoull(nptr, endptr, base, &tmp_endptr);
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label);
dfsan_strtolong_origin(nptr, tmp_endptr, base_label, ret_label, base_origin,
ret_origin);
return ret;
}
WRAPPER_ALIAS(__isoc23_strtod, strtod)

#define WRAPPER_STRTO(ret_type, fun) \
SANITIZER_INTERFACE_ATTRIBUTE ret_type __dfsw_##fun( \
const char *nptr, char **endptr, int base, dfsan_label nptr_label, \
dfsan_label endptr_label, dfsan_label base_label, \
dfsan_label *ret_label) { \
char *tmp_endptr; \
auto ret = dfsan_strtol_impl(fun, nptr, endptr, base, &tmp_endptr); \
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label); \
return ret; \
} \
SANITIZER_INTERFACE_ATTRIBUTE ret_type __dfso_##fun( \
const char *nptr, char **endptr, int base, dfsan_label nptr_label, \
dfsan_label endptr_label, dfsan_label base_label, \
dfsan_label *ret_label, dfsan_origin nptr_origin, \
dfsan_origin endptr_origin, dfsan_origin base_origin, \
dfsan_origin *ret_origin) { \
char *tmp_endptr; \
auto ret = dfsan_strtol_impl(fun, nptr, endptr, base, &tmp_endptr); \
dfsan_strtolong_label(nptr, tmp_endptr, base_label, ret_label); \
dfsan_strtolong_origin(nptr, tmp_endptr, base_label, ret_label, \
base_origin, ret_origin); \
return ret; \
}

WRAPPER_STRTO(long, strtol)
WRAPPER_STRTO(long long, strtoll)
WRAPPER_STRTO(unsigned long, strtoul)
WRAPPER_STRTO(unsigned long long, strtoull)
WRAPPER_ALIAS(__isoc23_strtol, strtol)
WRAPPER_ALIAS(__isoc23_strtoll, strtoll)
WRAPPER_ALIAS(__isoc23_strtoul, strtoul)
WRAPPER_ALIAS(__isoc23_strtoull, strtoull)

SANITIZER_INTERFACE_ATTRIBUTE
time_t __dfsw_time(time_t *t, dfsan_label t_label, dfsan_label *ret_label) {
Expand Down Expand Up @@ -2231,7 +2147,7 @@ SANITIZER_INTERFACE_ATTRIBUTE int __dfso_write(
*ret_label = 0;
return write(fd, buf, count);
}
} // namespace __dfsan
} // namespace __dfsan

// Type used to extract a dfsan_label with va_arg()
typedef int dfsan_label_va;
Expand Down Expand Up @@ -2866,31 +2782,8 @@ int __dfso_sscanf(char *str, const char *format, dfsan_label str_label,
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
int __dfsw___isoc99_sscanf(char *str, const char *format, dfsan_label str_label,
dfsan_label format_label, dfsan_label *va_labels,
dfsan_label *ret_label, ...) {
va_list ap;
va_start(ap, ret_label);
int ret = scan_buffer(str, ~0ul, format, va_labels, ret_label, nullptr,
nullptr, ap);
va_end(ap);
return ret;
}

SANITIZER_INTERFACE_ATTRIBUTE
int __dfso___isoc99_sscanf(char *str, const char *format, dfsan_label str_label,
dfsan_label format_label, dfsan_label *va_labels,
dfsan_label *ret_label, dfsan_origin str_origin,
dfsan_origin format_origin, dfsan_origin *va_origins,
dfsan_origin *ret_origin, ...) {
va_list ap;
va_start(ap, ret_origin);
int ret = scan_buffer(str, ~0ul, format, va_labels, ret_label, &str_origin,
ret_origin, ap);
va_end(ap);
return ret;
}
WRAPPER_ALIAS(__isoc99_sscanf, sscanf)
WRAPPER_ALIAS(__isoc23_sscanf, sscanf)

static void BeforeFork() {
StackDepotLockBeforeFork();
Expand Down
6 changes: 6 additions & 0 deletions compiler-rt/lib/dfsan/done_abilist.txt
View file
Original file line number Diff line number Diff line change
Expand Up @@ -270,6 +270,11 @@ fun:strtoul=custom
fun:strtoull=custom
fun:strcat=custom
fun:strncat=custom
fun:__isoc23_strtod=custom
fun:__isoc23_strtol=custom
fun:__isoc23_strtoll=custom
fun:__isoc23_strtoul=custom
fun:__isoc23_strtoull=custom

# Functions that produce an output that is computed from the input, but is not
# necessarily data dependent.
Expand Down Expand Up @@ -311,6 +316,7 @@ fun:snprintf=custom
# scanf-like
fun:sscanf=custom
fun:__isoc99_sscanf=custom
fun:__isoc23_sscanf=custom

# TODO: custom
fun:asprintf=discard
Expand Down
5 changes: 5 additions & 0 deletions compiler-rt/lib/dfsan/libc_ubuntu1404_abilist.txt
View file
Original file line number Diff line number Diff line change
@@ -1,3 +1,8 @@
fun:__isoc23_sscanf=uninstrumented
fun:__isoc23_strtol=uninstrumented
fun:__isoc23_strtoll=uninstrumented
fun:__isoc23_strtoul=uninstrumented
fun:__isoc23_strtoull=uninstrumented
fun:_Exit=uninstrumented
fun:_IO_adjust_column=uninstrumented
fun:_IO_adjust_wcolumn=uninstrumented
Expand Down

0 comments on commit 6485600

Please sign in to comment.