diff options
| author | Ben Hutchings <ben.hutchings@codethink.co.uk> | 2018-01-22 20:11:06 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-31 12:06:14 +0100 |
| commit | 3f84339bd344b2cf0afe64b78d3964bb6422d0f3 (patch) | |
| tree | b7526c3dd77113ee58295f4b06d12555eef8f5e0 | |
| parent | edaafa805e0f9d09560a4892790b8e19cab8bf09 (diff) | |
nfsd: auth: Fix gid sorting when rootsquash enabled
commit 1995266727fa8143897e89b55f5d3c79aa828420 upstream.
Commit bdcf0a423ea1 ("kernel: make groups_sort calling a responsibility
group_info allocators") appears to break nfsd rootsquash in a pretty
major way.
It adds a call to groups_sort() inside the loop that copies/squashes
gids, which means the valid gids are sorted along with the following
garbage. The net result is that the highest numbered valid gids are
replaced with any lower-valued garbage gids, possibly including 0.
We should sort only once, after filling in all the gids.
Fixes: bdcf0a423ea1 ("kernel: make groups_sort calling a responsibility ...")
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Wolfgang Walter <linux@stwm.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/nfsd/auth.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/fs/nfsd/auth.c b/fs/nfsd/auth.c index a260060042ad..67eb154af881 100644 --- a/fs/nfsd/auth.c +++ b/fs/nfsd/auth.c @@ -60,9 +60,10 @@ int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp) else GROUP_AT(gi, i) = GROUP_AT(rqgi, i); - /* Each thread allocates its own gi, no race */ - groups_sort(gi); } + + /* Each thread allocates its own gi, no race */ + groups_sort(gi); } else { gi = get_group_info(rqgi); } |