diff options
| author | Qinglang Miao <miaoqinglang@huawei.com> | 2020-12-10 09:29:43 +0800 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2020-12-16 10:10:32 -0500 |
| commit | 2d18e54dd8662442ef5898c6bdadeaf90b3cebbc (patch) | |
| tree | 62410b73261b6637ad0984221581500d85eefe09 /kernel | |
| parent | 5a7b5f32c5aa628841502d19a813c633ff6ecbe4 (diff) | |
cgroup: Fix memory leak when parsing multiple source parameters
A memory leak is found in cgroup1_parse_param() when multiple source
parameters overwrite fc->source in the fs_context struct without free.
unreferenced object 0xffff888100d930e0 (size 16):
comm "mount", pid 520, jiffies 4303326831 (age 152.783s)
hex dump (first 16 bytes):
74 65 73 74 6c 65 61 6b 00 00 00 00 00 00 00 00 testleak........
backtrace:
[<000000003e5023ec>] kmemdup_nul+0x2d/0xa0
[<00000000377dbdaa>] vfs_parse_fs_string+0xc0/0x150
[<00000000cb2b4882>] generic_parse_monolithic+0x15a/0x1d0
[<000000000f750198>] path_mount+0xee1/0x1820
[<0000000004756de2>] do_mount+0xea/0x100
[<0000000094cafb0a>] __x64_sys_mount+0x14b/0x1f0
Fix this bug by permitting a single source parameter and rejecting with
an error all subsequent ones.
Fixes: 8d2451f4994f ("cgroup1: switch to option-by-option parsing")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Reviewed-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cgroup/cgroup-v1.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c index 191c329e482a..32596fdbcd5b 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -908,6 +908,8 @@ int cgroup1_parse_param(struct fs_context *fc, struct fs_parameter *param) opt = fs_parse(fc, cgroup1_fs_parameters, param, &result); if (opt == -ENOPARAM) { if (strcmp(param->key, "source") == 0) { + if (fc->source) + return invalf(fc, "Multiple sources not supported"); fc->source = param->string; param->string = NULL; return 0; |