This is an archive of the discontinued LLVM Phabricator instance.

Differential D138386

[MSAN] add interceptor for stpncpy
ClosedPublic

Authored by GBuella on Nov 20 2022, 1:49 PM.

Details

Reviewers
vitalybuka
Commits
rGe49a6c3d7f50: [MSAN] add interceptor for stpncpy

Diff Detail

Event Timeline

GBuella created this revision.Nov 20 2022, 1:49 PM
Herald added a project: Restricted Project. · View Herald TranscriptNov 20 2022, 1:49 PM
Herald added a subscriber: Enna1. · View Herald Transcript
GBuella requested review of this revision.Nov 20 2022, 1:49 PM
Herald added a subscriber: Restricted Project. · View Herald TranscriptNov 20 2022, 1:49 PM
GBuella added a reviewer: vitalybuka.Nov 20 2022, 1:52 PM
Harbormaster completed remote builds in B198693: Diff 476773.Nov 20 2022, 2:36 PM
GBuella updated this revision to Diff 477089.Nov 22 2022, 12:33 AM

Fixed indentation

Harbormaster completed remote builds in B198920: Diff 477089.Nov 22 2022, 1:50 AM
vitalybuka accepted this revision.Nov 28 2022, 3:20 PM
vitalybuka added inline comments.
compiler-rt/lib/msan/msan_interceptors.cpp
329–331
This revision is now accepted and ready to land.Nov 28 2022, 3:20 PM
Closed by commit rGe49a6c3d7f50: [MSAN] add interceptor for stpncpy (authored by GBuella). · Explain WhyNov 30 2022, 3:24 AM
This revision was automatically updated to reflect the committed changes.
GBuella added a commit: rGe49a6c3d7f50: [MSAN] add interceptor for stpncpy.

Revision Contents

PathSize
compiler-rt/
lib/
msan/
15 lines
tests/
15 lines

Diff 476773

compiler-rt/lib/msan/msan_interceptors.cpp

Show First 20 Lines • Show All 304 Lines • ▼ Show 20 LinesINTERCEPTOR(char *, stpcpy, char *dest, const char *src) {
ENSURE_MSAN_INITED(); ENSURE_MSAN_INITED();
GET_STORE_STACK_TRACE; GET_STORE_STACK_TRACE;
SIZE_T n = internal_strlen(src); SIZE_T n = internal_strlen(src);
CHECK_UNPOISONED_STRING(src + n, 0); CHECK_UNPOISONED_STRING(src + n, 0);
char *res = REAL(stpcpy)(dest, src); char *res = REAL(stpcpy)(dest, src);
CopyShadowAndOrigin(dest, src, n + 1, &stack); CopyShadowAndOrigin(dest, src, n + 1, &stack);
return res; return res;
} }
INTERCEPTOR(char *, stpncpy, char *dest, const char *src, SIZE_T n) {
ENSURE_MSAN_INITED();
GET_STORE_STACK_TRACE;
SIZE_T copy_size = internal_strnlen(src, n);
if (copy_size < n)
copy_size++; // trailing \0
char *res = REAL(stpncpy)(dest, src, n);
CopyShadowAndOrigin(dest, src, copy_size, &stack);
__msan_unpoison(dest + copy_size, n - copy_size);
return res;
}
#define MSAN_MAYBE_INTERCEPT_STPCPY INTERCEPT_FUNCTION(stpcpy) #define MSAN_MAYBE_INTERCEPT_STPCPY INTERCEPT_FUNCTION(stpcpy)
#define MSAN_MAYBE_INTERCEPT_STPNCPY INTERCEPT_FUNCTION(stpncpy)
#else #else
#define MSAN_MAYBE_INTERCEPT_STPCPY #define MSAN_MAYBE_INTERCEPT_STPCPY
#define MSAN_MAYBE_INTERCEPT_STPNCPY
#endif #endif
vitalybukaUnsubmitted
Not Done
ReplyInline Actions
GET_STORE_STACK_TRACE;
- SIZE_T copy_size = internal_strnlen(src, n);
- if (copy_size < n)
- copy_size++; // trailing \0
- char *res = REAL(stpncpy)(dest, src, n);
+ SIZE_T copy_size = Min(n, internal_strnlen(src, n) + 1); char *res = REAL(stpncpy)(dest, src, n);
vitalybuka:
INTERCEPTOR(char *, strdup, char *src) { INTERCEPTOR(char *, strdup, char *src) {
ENSURE_MSAN_INITED(); ENSURE_MSAN_INITED();
GET_STORE_STACK_TRACE; GET_STORE_STACK_TRACE;
// On FreeBSD strdup() leverages strlen(). // On FreeBSD strdup() leverages strlen().
InterceptorScope interceptor_scope; InterceptorScope interceptor_scope;
SIZE_T n = internal_strlen(src); SIZE_T n = internal_strlen(src);
CHECK_UNPOISONED_STRING(src + n, 0); CHECK_UNPOISONED_STRING(src + n, 0);
char *res = REAL(strdup)(src); char *res = REAL(strdup)(src);
▲ Show 20 Lines • Show All 1,355 Lines • ▼ Show 20 Linesvoid InitializeInterceptors() {
MSAN_MAYBE_INTERCEPT_MEMPCPY; MSAN_MAYBE_INTERCEPT_MEMPCPY;
INTERCEPT_FUNCTION(bcopy); INTERCEPT_FUNCTION(bcopy);
INTERCEPT_FUNCTION(wmemset); INTERCEPT_FUNCTION(wmemset);
INTERCEPT_FUNCTION(wmemcpy); INTERCEPT_FUNCTION(wmemcpy);
MSAN_MAYBE_INTERCEPT_WMEMPCPY; MSAN_MAYBE_INTERCEPT_WMEMPCPY;
INTERCEPT_FUNCTION(wmemmove); INTERCEPT_FUNCTION(wmemmove);
INTERCEPT_FUNCTION(strcpy); INTERCEPT_FUNCTION(strcpy);
MSAN_MAYBE_INTERCEPT_STPCPY; MSAN_MAYBE_INTERCEPT_STPCPY;
MSAN_MAYBE_INTERCEPT_STPNCPY;
INTERCEPT_FUNCTION(strdup); INTERCEPT_FUNCTION(strdup);
MSAN_MAYBE_INTERCEPT___STRDUP; MSAN_MAYBE_INTERCEPT___STRDUP;
INTERCEPT_FUNCTION(strncpy); INTERCEPT_FUNCTION(strncpy);
MSAN_MAYBE_INTERCEPT_GCVT; MSAN_MAYBE_INTERCEPT_GCVT;
INTERCEPT_FUNCTION(strcat); INTERCEPT_FUNCTION(strcat);
INTERCEPT_FUNCTION(strncat); INTERCEPT_FUNCTION(strncat);
INTERCEPT_STRTO(strtod); INTERCEPT_STRTO(strtod);
INTERCEPT_STRTO(strtof); INTERCEPT_STRTO(strtof);
▲ Show 20 Lines • Show All 88 Lines • Show Last 20 Lines

compiler-rt/lib/msan/tests/msan_test.cpp

Show First 20 Lines • Show All 1,681 Lines • ▼ Show 20 LinesTEST(MemorySanitizer, stpcpy) {
x[2] = 0; x[2] = 0;
char *res = stpcpy(y, x); char *res = stpcpy(y, x);
ASSERT_EQ(res, y + 2); ASSERT_EQ(res, y + 2);
EXPECT_NOT_POISONED(y[0]); EXPECT_NOT_POISONED(y[0]);
EXPECT_POISONED(y[1]); EXPECT_POISONED(y[1]);
EXPECT_NOT_POISONED(y[2]); EXPECT_NOT_POISONED(y[2]);
} }
TEST(MemorySanitizer, stpncpy) {
char* x = new char[3];
char* y = new char[5];
x[0] = 'a';
x[1] = *GetPoisoned<char>(1, 1);
x[2] = '\0';
char *res = stpncpy(y, x, 4);
ASSERT_EQ(res, y + 2);
EXPECT_NOT_POISONED(y[0]);
EXPECT_POISONED(y[1]);
EXPECT_NOT_POISONED(y[2]);
EXPECT_NOT_POISONED(y[3]);
EXPECT_POISONED(y[4]);
}
TEST(MemorySanitizer, strcat) { TEST(MemorySanitizer, strcat) {
char a[10]; char a[10];
char b[] = "def"; char b[] = "def";
strcpy(a, "abc"); strcpy(a, "abc");
__msan_poison(b + 1, 1); __msan_poison(b + 1, 1);
strcat(a, b); strcat(a, b);
EXPECT_NOT_POISONED(a[3]); EXPECT_NOT_POISONED(a[3]);
EXPECT_POISONED(a[4]); EXPECT_POISONED(a[4]);
▲ Show 20 Lines • Show All 3,170 Lines • Show Last 20 Lines