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| author | Carlos O'Donell <carlos@redhat.com> | 2013-09-23 00:52:09 -0400 |
|---|---|---|
| committer | Carlos O'Donell <carlos@redhat.com> | 2013-09-23 00:52:09 -0400 |
| commit | c61b4d41c9647a54a329aa021341c0eb032b793e (patch) | |
| tree | c4a665c232a7d37786a6f3b5e3f56d0ae11480e8 /sysdeps/i386 | |
| parent | 58a96064d193317236b740998e134b652d3d62ad (diff) | |
| download | glibc-c61b4d41c9647a54a329aa021341c0eb032b793e.zip glibc-c61b4d41c9647a54a329aa021341c0eb032b793e.tar.gz glibc-c61b4d41c9647a54a329aa021341c0eb032b793e.tar.bz2 | |
BZ #15754: CVE-2013-4788
The pointer guard used for pointer mangling was not initialized for
static applications resulting in the security feature being disabled.
The pointer guard is now correctly initialized to a random value for
static applications. Existing static applications need to be
recompiled to take advantage of the fix.
The test tst-ptrguard1-static and tst-ptrguard1 add regression
coverage to ensure the pointer guards are sufficiently random
and initialized to a default value.
Diffstat (limited to 'sysdeps/i386')
| -rw-r--r-- | sysdeps/i386/stackguard-macros.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/sysdeps/i386/stackguard-macros.h b/sysdeps/i386/stackguard-macros.h index 8c31e19..0397629 100644 --- a/sysdeps/i386/stackguard-macros.h +++ b/sysdeps/i386/stackguard-macros.h @@ -2,3 +2,11 @@ #define STACK_CHK_GUARD \ ({ uintptr_t x; asm ("movl %%gs:0x14, %0" : "=r" (x)); x; }) + +#define POINTER_CHK_GUARD \ + ({ \ + uintptr_t x; \ + asm ("movl %%gs:%c1, %0" : "=r" (x) \ + : "i" (offsetof (tcbhead_t, pointer_guard))); \ + x; \ + }) |