Commit f3b3e543bc4eb3990cba4a331c5ec96a9835a8df
2019-08-08T11:34:01
xdiff: catch memory allocation errors The xdiff code contains multiple call sites where the results of `xdl_malloc` are not being checked for memory allocation errors. Add checks to fix possible segfaults due to `NULL` pointer accesses.
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diff --git a/src/xdiff/xmerge.c b/src/xdiff/xmerge.c
index e6eaf24..278cbe1 100644
--- a/src/xdiff/xmerge.c
+++ b/src/xdiff/xmerge.c
@@ -717,10 +717,22 @@ int xdl_merge(mmfile_t *orig, mmfile_t *mf1, mmfile_t *mf2,
status = 0;
if (!xscr1) {
result->ptr = xdl_malloc(mf2->size);
+ if (!result->ptr) {
+ xdl_free_script(xscr2);
+ xdl_free_env(&xe1);
+ xdl_free_env(&xe2);
+ return -1;
+ }
memcpy(result->ptr, mf2->ptr, mf2->size);
result->size = mf2->size;
} else if (!xscr2) {
result->ptr = xdl_malloc(mf1->size);
+ if (!result->ptr) {
+ xdl_free_script(xscr1);
+ xdl_free_env(&xe1);
+ xdl_free_env(&xe2);
+ return -1;
+ }
memcpy(result->ptr, mf1->ptr, mf1->size);
result->size = mf1->size;
} else {
diff --git a/src/xdiff/xpatience.c b/src/xdiff/xpatience.c
index cedf39c..53b7d5f 100644
--- a/src/xdiff/xpatience.c
+++ b/src/xdiff/xpatience.c
@@ -217,6 +217,9 @@ static struct entry *find_longest_common_sequence(struct hashmap *map)
*/
int anchor_i = -1;
+ if (!sequence)
+ return NULL;
+
for (entry = map->first; entry; entry = entry->next) {
if (!entry->line2 || entry->line2 == NON_UNIQUE)
continue;