| Brad Bishop | 1a4b7ee | 2018-12-16 17:11:34 -0800 | [diff] [blame^] | 1 | libxml2-2.9.8: Fix CVE-2018-14404 |
| 2 | |
| 3 | [No upstream tracking] -- https://gitlab.gnome.org/GNOME/libxml2/issues/5 |
| 4 | -- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=901817 |
| 5 | -- https://bugzilla.redhat.com/show_bug.cgi?id=1595985 |
| 6 | |
| 7 | xpath: Fix nullptr deref with XPath logic ops |
| 8 | |
| 9 | If the XPath stack is corrupted, for example by a misbehaving extension |
| 10 | function, the "and" and "or" XPath operators could dereference NULL |
| 11 | pointers. Check that the XPath stack isn't empty and optimize the |
| 12 | logic operators slightly. |
| 13 | |
| 14 | Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/libxml2/commit/a436374994c47b12d5de1b8b1d191a098fa23594] |
| 15 | CVE: CVE-2018-14404 |
| 16 | Signed-off-by: Andrej Valek <andrej.valek@siemens.com> |
| 17 | |
| 18 | diff --git a/xpath.c b/xpath.c |
| 19 | index f440696..75cac5c 100644 |
| 20 | --- a/xpath.c |
| 21 | +++ b/xpath.c |
| 22 | @@ -13297,9 +13297,8 @@ xmlXPathCompOpEval(xmlXPathParserContextPtr ctxt, xmlXPathStepOpPtr op) |
| 23 | return(0); |
| 24 | } |
| 25 | xmlXPathBooleanFunction(ctxt, 1); |
| 26 | - arg1 = valuePop(ctxt); |
| 27 | - arg1->boolval &= arg2->boolval; |
| 28 | - valuePush(ctxt, arg1); |
| 29 | + if (ctxt->value != NULL) |
| 30 | + ctxt->value->boolval &= arg2->boolval; |
| 31 | xmlXPathReleaseObject(ctxt->context, arg2); |
| 32 | return (total); |
| 33 | case XPATH_OP_OR: |
| 34 | @@ -13323,9 +13322,8 @@ xmlXPathCompOpEval(xmlXPathParserContextPtr ctxt, xmlXPathStepOpPtr op) |
| 35 | return(0); |
| 36 | } |
| 37 | xmlXPathBooleanFunction(ctxt, 1); |
| 38 | - arg1 = valuePop(ctxt); |
| 39 | - arg1->boolval |= arg2->boolval; |
| 40 | - valuePush(ctxt, arg1); |
| 41 | + if (ctxt->value != NULL) |
| 42 | + ctxt->value->boolval |= arg2->boolval; |
| 43 | xmlXPathReleaseObject(ctxt->context, arg2); |
| 44 | return (total); |
| 45 | case XPATH_OP_EQUAL: |