aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorQinglang Miao <miaoqinglang@huawei.com>2020-12-10 09:29:43 +0800
committerTejun Heo <tj@kernel.org>2020-12-16 10:10:32 -0500
commit2d18e54dd8662442ef5898c6bdadeaf90b3cebbc (patch)
tree62410b73261b6637ad0984221581500d85eefe09
parent5a7b5f32c5aa628841502d19a813c633ff6ecbe4 (diff)
downloadlinux-stericsson-2d18e54dd8662442ef5898c6bdadeaf90b3cebbc.tar.gz
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>
-rw-r--r--kernel/cgroup/cgroup-v1.c2
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;