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| author | Mike DePaulo <mikedep333@gmail.com> | 2015-02-08 21:03:33 -0500 |
|---|---|---|
| committer | Mike Gabriel <mike.gabriel@das-netzwerkteam.de> | 2015-02-14 16:14:31 +0100 |
| commit | 94c6de0649cd295044b1e4ff7265949c9c787519 (patch) | |
| tree | a9a795efb5f4c84e078fd594c2535e914f5762e5 /nx-X11 | |
| parent | 36f1dae749acb065eaefca56d42d19ef6822a001 (diff) | |
| download | nx-libs-94c6de0649cd295044b1e4ff7265949c9c787519.tar.gz nx-libs-94c6de0649cd295044b1e4ff7265949c9c787519.tar.bz2 nx-libs-94c6de0649cd295044b1e4ff7265949c9c787519.zip | |
CVE-2014-0210: unvalidated length in _fs_recv_conn_setup() from xorg/lib/libXfont commit 891e084b26837162b12f841060086a105edde86d
The connection setup reply from the font server can include a list
of alternate servers to contact if this font server stops working.
The reply specifies a total size of all the font server names, and
then provides a list of names. _fs_recv_conn_setup() allocated the
specified total size for copying the names to, but didn't check to
make sure it wasn't copying more data to that buffer than the size
it had allocated.
Diffstat (limited to 'nx-X11')
| -rw-r--r-- | nx-X11/lib/font/fc/fserve.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/nx-X11/lib/font/fc/fserve.c b/nx-X11/lib/font/fc/fserve.c index bac0b8ee6..0fdcc1d84 100644 --- a/nx-X11/lib/font/fc/fserve.c +++ b/nx-X11/lib/font/fc/fserve.c @@ -2782,7 +2782,7 @@ _fs_recv_conn_setup (FSFpePtr conn) int ret; fsConnSetup *setup; FSFpeAltPtr alts; - int i, alt_len; + unsigned int i, alt_len; int setup_len; char *alt_save, *alt_names; @@ -2809,9 +2809,9 @@ _fs_recv_conn_setup (FSFpePtr conn) } if (setup->num_alternates) { + size_t alt_name_len = setup->alternate_len << 2; alts = (FSFpeAltPtr) xalloc (setup->num_alternates * - sizeof (FSFpeAltRec) + - (setup->alternate_len << 2)); + sizeof (FSFpeAltRec) + alt_name_len); if (alts) { alt_names = (char *) (setup + 1); @@ -2820,10 +2820,25 @@ _fs_recv_conn_setup (FSFpePtr conn) { alts[i].subset = alt_names[0]; alt_len = alt_names[1]; + if (alt_len >= alt_name_len) { + /* + * Length is longer than setup->alternate_len + * told us to allocate room for, assume entire + * alternate list is corrupted. + */ +#ifdef DEBUG + fprintf (stderr, + "invalid alt list (length %lx >= %lx)\n", + (long) alt_len, (long) alt_name_len); +#endif + free(alts); + return FSIO_ERROR; + } alts[i].name = alt_save; memcpy (alt_save, alt_names + 2, alt_len); alt_save[alt_len] = '\0'; alt_save += alt_len + 1; + alt_name_len -= alt_len + 1; alt_names += _fs_pad_length (alt_len + 2); } conn->numAlts = setup->num_alternates; |