libxml2/Fix-integer-overflow-when-parsing-min-max-Occurs.patch
2020-09-10 10:31:12 +08:00

56 lines
1.5 KiB
Diff

From 070d635e771a24f33e8480fa60689a881c9fa636 Mon Sep 17 00:00:00 2001
From: Nick Wellnhofer <wellnhofer@aevum.de>
Date: Sun, 21 Jun 2020 16:26:38 +0200
Subject: [PATCH 059/139] Fix integer overflow when parsing {min,max}Occurs
Clamp value to INT_MAX.
Found with libFuzzer and UBSan.
---
xmlschemas.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)
diff --git a/xmlschemas.c b/xmlschemas.c
index 81c47bc..cc20063 100644
--- a/xmlschemas.c
+++ b/xmlschemas.c
@@ -6074,7 +6074,16 @@ xmlGetMaxOccurs(xmlSchemaParserCtxtPtr ctxt, xmlNodePtr node,
return (def);
}
while ((*cur >= '0') && (*cur <= '9')) {
- ret = ret * 10 + (*cur - '0');
+ if (ret > INT_MAX / 10) {
+ ret = INT_MAX;
+ } else {
+ int digit = *cur - '0';
+ ret *= 10;
+ if (ret > INT_MAX - digit)
+ ret = INT_MAX;
+ else
+ ret += digit;
+ }
cur++;
}
while (IS_BLANK_CH(*cur))
@@ -6126,7 +6135,16 @@ xmlGetMinOccurs(xmlSchemaParserCtxtPtr ctxt, xmlNodePtr node,
return (def);
}
while ((*cur >= '0') && (*cur <= '9')) {
- ret = ret * 10 + (*cur - '0');
+ if (ret > INT_MAX / 10) {
+ ret = INT_MAX;
+ } else {
+ int digit = *cur - '0';
+ ret *= 10;
+ if (ret > INT_MAX - digit)
+ ret = INT_MAX;
+ else
+ ret += digit;
+ }
cur++;
}
while (IS_BLANK_CH(*cur))
--
1.8.3.1