In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix memory leak in __add_inode_ref()
Line 1169 (#3) allocates a memory chunk for victim_name by kmalloc(),
but when the function returns in line 1184 (#4) victim_name allocated
by line 1169 (#3) is not freed, which will lead to a memory leak.
There is a similar snippet of code in this function as allocating a memory
chunk for victim_name in line 1104 (#1) as well as releasing the memory
in line 1116 (#2).
We should kfree() victim_name when the return value of backref_in_log()
is less than zero and before the function returns in line 1184 (#4).
1057 static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
1058 struct btrfs_root *root,
1059 struct btrfs_path *path,
1060 struct btrfs_root *log_root,
1061 struct btrfs_inode *dir,
1062 struct btrfs_inode *inode,
1063 u64 inode_objectid, u64 parent_objectid,
1064 u64 ref_index, char *name, int namelen,
1065 int *search_done)
1066 {
1104 victim_name = kmalloc(victim_name_len, GFP_NOFS);
// #1: kmalloc (victim_name-1)
1105 if (!victim_name)
1106 return -ENOMEM;
1112 ret = backref_in_log(log_root, &search_key,
1113 parent_objectid, victim_name,
1114 victim_name_len);
1115 if (ret < 0) {
1116 kfree(victim_name); // #2: kfree (victim_name-1)
1117 return ret;
1118 } else if (!ret) {
1169 victim_name = kmalloc(victim_name_len, GFP_NOFS);
// #3: kmalloc (victim_name-2)
1170 if (!victim_name)
1171 return -ENOMEM;
1180 ret = backref_in_log(log_root, &search_key,
1181 parent_objectid, victim_name,
1182 victim_name_len);
1183 if (ret < 0) {
1184 return ret; // #4: missing kfree (victim_name-2)
1185 } else if (!ret) {
1241 return 0;
1242 }
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"fs/btrfs/tree-log.c"
],
"versions": [
{
"version": "d3316c8233bb",
"lessThan": "005d9292b5b2",
"status": "affected",
"versionType": "git"
},
{
"version": "d3316c8233bb",
"lessThan": "493ff661d434",
"status": "affected",
"versionType": "git"
},
{
"version": "d3316c8233bb",
"lessThan": "f35838a69302",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"fs/btrfs/tree-log.c"
],
"versions": [
{
"version": "5.5",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.5",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.10.88",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.15.11",
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.16",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]