CVE-2019-13105: ext4: fix double-free in ext4_cache_read
ext_cache_read doesn't null cache->buf, after freeing, which results
in a later function double-freeing it. This patch fixes
ext_cache_read to call ext_cache_fini instead of free.
Signed-off-by: Paul Emge <paulemge@forallsecure.com>
diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c
index 26db677..85dc122 100644
--- a/fs/ext4/ext4fs.c
+++ b/fs/ext4/ext4fs.c
@@ -286,7 +286,7 @@
if (!cache->buf)
return 0;
if (!ext4fs_devread(block, 0, size, cache->buf)) {
- free(cache->buf);
+ ext_cache_fini(cache);
return 0;
}
cache->block = block;