From e29bbd5bf0565eaf7c02f85a57b87f66531fa6b3 Mon Sep 17 00:00:00 2001 From: Mike DePaulo Date: Sun, 8 Feb 2015 22:08:09 -0500 Subject: CVE-2014-0210: unvalidated length fields in fs_read_query_info() from xorg/lib/libXfont commit 491291cabf78efdeec8f18b09e14726a9030cc8f fs_read_query_info() parses a reply from the font server. The reply contains embedded length fields, none of which are validated. This can cause out of bound reads in either fs_read_query_info() or in _fs_convert_props() which it calls to parse the fsPropInfo in the reply. v2: apply correctly on nx-libs 3.6.x (Mihai Moldovan) --- nx-X11/lib/font/fc/fsconvert.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'nx-X11/lib/font/fc/fsconvert.c') diff --git a/nx-X11/lib/font/fc/fsconvert.c b/nx-X11/lib/font/fc/fsconvert.c index 9a5e194d1..afa2c3284 100644 --- a/nx-X11/lib/font/fc/fsconvert.c +++ b/nx-X11/lib/font/fc/fsconvert.c @@ -123,6 +123,10 @@ _fs_convert_props(fsPropInfo *pi, fsPropOffset *po, pointer pd, for (i = 0; i < nprops; i++, dprop++, is_str++) { memcpy(&local_off, off_adr, SIZEOF(fsPropOffset)); + if ((local_off.name.position >= pi->data_len) || + (local_off.name.length > + (pi->data_len - local_off.name.position))) + goto bail; dprop->name = MakeAtom(&pdc[local_off.name.position], local_off.name.length, 1); if (local_off.type != PropTypeString) { @@ -130,15 +134,20 @@ _fs_convert_props(fsPropInfo *pi, fsPropOffset *po, pointer pd, dprop->value = local_off.value.position; } else { *is_str = TRUE; + if ((local_off.value.position >= pi->data_len) || + (local_off.value.length > + (pi->data_len - local_off.value.position))) + goto bail; dprop->value = (INT32) MakeAtom(&pdc[local_off.value.position], local_off.value.length, 1); if (dprop->value == BAD_RESOURCE) { - xfree (pfi->props); - pfi->nprops = 0; - pfi->props = 0; - pfi->isStringProp = 0; - return -1; + bail: + xfree (pfi->props); + pfi->nprops = 0; + pfi->props = 0; + pfi->isStringProp = 0; + return -1; } } off_adr += SIZEOF(fsPropOffset); -- cgit v1.2.3