redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

nfsd: auth: Fix gid sorting when rootsquash enabled 

Commit bdcf0a423e ("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: bdcf0a423e ("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>
hifive-unleashed-5.1
Ben Hutchings 2018-01-22 20:11:06 +00:00 committed by Linus Torvalds
parent a0ec1ded22
commit 1995266727
1 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
fs/nfsd/auth.c
View File

@ -60,10 +60,10 @@ int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp)
gi->gid[i] = exp->ex_anon_gid;
else
gi->gid[i] = rqgi->gid[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);
}