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| author | Mike DePaulo <mikedep333@gmail.com> | 2015-02-08 20:53:14 -0500 |
|---|---|---|
| committer | Mike Gabriel <mike.gabriel@das-netzwerkteam.de> | 2015-02-14 16:14:31 +0100 |
| commit | 36f1dae749acb065eaefca56d42d19ef6822a001 (patch) | |
| tree | 81987135f66470a51c043d5b22b5e752ee340355 | |
| parent | f53f2474d5d33cca04c4c7744ecc50cec41ba94f (diff) | |
| download | nx-libs-36f1dae749acb065eaefca56d42d19ef6822a001.tar.gz nx-libs-36f1dae749acb065eaefca56d42d19ef6822a001.tar.bz2 nx-libs-36f1dae749acb065eaefca56d42d19ef6822a001.zip | |
CVE-2014-0209: integer overflow of realloc() size in lexAlias() from xorg/lib/libXfont commit 05c8020a49416dd8b7510cbba45ce4f3fc81a7dc
lexAlias() reads from a file in a loop. It does this by starting with a
64 byte buffer. If that size limit is hit, it does a realloc of the
buffer size << 1, basically doubling the needed length every time the
length limit is hit.
Eventually, this will shift out to 0 (for a length of ~4gig), and that
length will be passed on to realloc(). A length of 0 (with a valid
pointer) causes realloc to free the buffer on most POSIX platforms,
but the caller will still have a pointer to it, leading to use after
free issues.
| -rw-r--r-- | nx-X11/lib/font/fontfile/dirfile.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/nx-X11/lib/font/fontfile/dirfile.c b/nx-X11/lib/font/fontfile/dirfile.c index f390391bc..3a2fead81 100644 --- a/nx-X11/lib/font/fontfile/dirfile.c +++ b/nx-X11/lib/font/fontfile/dirfile.c @@ -45,6 +45,7 @@ in this Software without prior written authorization from The Open Group. #include <sys/types.h> #include <sys/stat.h> #include <errno.h> +#include <limits.h> static Bool AddFileNameAliases ( FontDirectoryPtr dir ); static int ReadFontAlias ( char *directory, Bool isFile, @@ -373,6 +374,9 @@ lexAlias(FILE *file, char **lexToken) int nsize; char *nbuf; + if (tokenSize >= (INT_MAX >> 2)) + /* Stop before we overflow */ + return EALLOC; nsize = tokenSize ? (tokenSize << 1) : 64; nbuf = (char *) xrealloc(tokenBuf, nsize); if (!nbuf) |