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| author | H.J. Lu <hjl.tools@gmail.com> | 2017-07-24 06:06:08 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2017-07-24 06:06:24 -0700 |
| commit | 422ff87c249ddc06701d096421db63343e4754be (patch) | |
| tree | e095970d350bffebdd21f9fa75a24494aeebbc47 /debug | |
| parent | 55703fcace89b53d7f41f7d85ede50571da2bcc8 (diff) | |
| download | glibc-422ff87c249ddc06701d096421db63343e4754be.zip glibc-422ff87c249ddc06701d096421db63343e4754be.tar.gz glibc-422ff87c249ddc06701d096421db63343e4754be.tar.bz2 | |
Avoid accessing corrupted stack from __stack_chk_fail [BZ #21752]
__libc_argv[0] points to address on stack and __libc_secure_getenv
accesses environment variables which are on stack. We should avoid
accessing stack when stack is corrupted.
This patch also renames function argument in __fortify_fail_abort
from do_backtrace to need_backtrace to avoid confusion with do_backtrace
from enum __libc_message_action.
[BZ #21752]
* debug/fortify_fail.c (__fortify_fail_abort): Don't pass down
__libc_argv[0] if we aren't doing backtrace. Rename do_backtrace
to need_backtrace.
* sysdeps/posix/libc_fatal.c (__libc_message): Don't call
__libc_secure_getenv if we aren't doing backtrace.
Diffstat (limited to 'debug')
| -rw-r--r-- | debug/fortify_fail.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/debug/fortify_fail.c b/debug/fortify_fail.c index c90d384..a0777ae 100644 --- a/debug/fortify_fail.c +++ b/debug/fortify_fail.c @@ -24,13 +24,17 @@ extern char **__libc_argv attribute_hidden; void __attribute__ ((noreturn)) internal_function -__fortify_fail_abort (_Bool do_backtrace, const char *msg) +__fortify_fail_abort (_Bool need_backtrace, const char *msg) { - /* The loop is added only to keep gcc happy. */ + /* The loop is added only to keep gcc happy. Don't pass down + __libc_argv[0] if we aren't doing backtrace since __libc_argv[0] + may point to the corrupted stack. */ while (1) - __libc_message (do_backtrace ? (do_abort | do_backtrace) : do_abort, + __libc_message (need_backtrace ? (do_abort | do_backtrace) : do_abort, "*** %s ***: %s terminated\n", - msg, __libc_argv[0] ?: "<unknown>"); + msg, + (need_backtrace && __libc_argv[0] != NULL + ? __libc_argv[0] : "<unknown>")); } void |