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| author | Ondrej Mosnacek <omosnace@redhat.com> | 2018-12-13 15:17:37 +0100 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2018-12-28 19:32:57 +0100 |
| commit | e250d91d65750a0c0c62483ac4f9f357e7317617 (patch) | |
| tree | cb40d16ec1d7a2c6b30a7b42c7a525db6f8e79df | |
| parent | Merge branch 'for-4.20-fixes' into for-4.21 (diff) | |
| download | linux-e250d91d65750a0c0c62483ac4f9f357e7317617.tar.xz linux-e250d91d65750a0c0c62483ac4f9f357e7317617.zip | |
cgroup: fix parsing empty mount option string
This fixes the case where all mount options specified are consumed by an
LSM and all that's left is an empty string. In this case cgroupfs should
accept the string and not fail.
How to reproduce (with SELinux enabled):
# umount /sys/fs/cgroup/unified
# mount -o context=system_u:object_r:cgroup_t:s0 -t cgroup2 cgroup2 /sys/fs/cgroup/unified
mount: /sys/fs/cgroup/unified: wrong fs type, bad option, bad superblock on cgroup2, missing codepage or helper program, or other error.
# dmesg | tail -n 1
[ 31.575952] cgroup: cgroup2: unknown option ""
Fixes: 67e9c74b8a87 ("cgroup: replace __DEVEL__sane_behavior with cgroup2 fs type")
[NOTE: should apply on top of commit 5136f6365ce3 ("cgroup: implement "nsdelegate" mount option"), older versions need manual rebase]
Suggested-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
| -rw-r--r-- | kernel/cgroup/cgroup.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 8da9bf5e422f..879c9f191f66 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -1748,7 +1748,7 @@ static int parse_cgroup_root_flags(char *data, unsigned int *root_flags) *root_flags = 0; - if (!data) + if (!data || *data == '\0') return 0; while ((token = strsep(&data, ",")) != NULL) { |