Commit 24c031b1 authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

Don't use checked strl{cat,cpy} on OSX. 

There is a bug in the overlap-checking in strlcat that can crash Tor
servers.  Fixes bug 15205; this is an OSX bug, not a Tor bug.
parent 68180281

changes/bug15205

0 → 100644
+5 −0
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  o Major bugfixes (crash, OSX, security):

    - Fix a remote denial-of-service opportunity caused by a bug

      in OSX's _strlcat_chk() function. Fixes bug 15205; bug first

      appeared in OSX 10.9.

src/common/compat.h

+12 −0
Original line number Diff line number Diff line
@@ -224,6 +224,18 @@ extern INLINE double U64_TO_DBL(uint64_t x) { 
#define strncasecmp _strnicmp

#define strcasecmp _stricmp

#endif



#if defined __APPLE__

/* On OSX 10.9 and later, the overlap-checking code for strlcat would

 * appear to have a severe bug that can sometimes cause aborts in Tor.

 * Instead, use the non-checking variants.  This is sad.

 *

 * See https://trac.torproject.org/projects/tor/ticket/15205

 */

#undef strlcat

#undef strlcpy

#endif



#ifndef HAVE_STRLCAT

size_t strlcat(char *dst, const char *src, size_t siz) ATTR_NONNULL((1,2));

#endif