diff options
author | Matt Caswell <matt@openssl.org> | 2016-10-12 16:43:03 +0100 |
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committer | Matt Caswell <matt@openssl.org> | 2016-10-15 11:32:24 +0100 |
commit | 953ef2cbd0645a47b8d5c1af3fe8f77f2e56c133 (patch) | |
tree | 92180f9eff64bba47a636ff1b2672048edb229ca /crypto | |
parent | 5389388a2b327ab5d4353e98b4e258fb683cde15 (diff) |
Ensure we handle len == 0 in ERR_err_string_n
If len == 0 in a call to ERR_error_string_n() then we can read beyond the
end of the buffer. Really applications should not be calling this function
with len == 0, but we shouldn't be letting it through either!
Thanks to Agostino Sarubbo for reporting this issue. Agostino's blog on
this issue is available here:
https://blogs.gentoo.org/ago/2016/10/14/openssl-libcrypto-stack-based-buffer-overflow-in-err_error_string_n-err-c/
Reviewed-by: Richard Levitte <levitte@openssl.org>
(cherry picked from commit e5c1361580d8de79682958b04a5f0d262e680f8b)
Diffstat (limited to 'crypto')
-rw-r--r-- | crypto/err/err.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/crypto/err/err.c b/crypto/err/err.c index c3f7212a78..29e5a03197 100644 --- a/crypto/err/err.c +++ b/crypto/err/err.c @@ -500,6 +500,9 @@ void ERR_error_string_n(unsigned long e, char *buf, size_t len) const char *ls, *fs, *rs; unsigned long l, f, r; + if (len == 0) + return; + l = ERR_GET_LIB(e); f = ERR_GET_FUNC(e); r = ERR_GET_REASON(e); |