diff options
| author | Amir Goldstein <amir73il@gmail.com> | 2018-07-13 17:22:24 +0300 |
|---|---|---|
| committer | J. Bruce Fields <bfields@redhat.com> | 2018-08-09 16:11:21 -0400 |
| commit | 64bed6cbe38bc95689fb9399872d9ce250192f90 (patch) | |
| tree | 6376a71e746622c32818abd785c05a09593a01a8 /fs/lockd/clntproc.c | |
| parent | 8163496e78db100a6b5cfbdaece385686ae50129 (diff) | |
| download | lwn-64bed6cbe38bc95689fb9399872d9ce250192f90.tar.gz lwn-64bed6cbe38bc95689fb9399872d9ce250192f90.zip | |
nfsd: fix leaked file lock with nfs exported overlayfs
nfsd and lockd call vfs_lock_file() to lock/unlock the inode
returned by locks_inode(file).
Many places in nfsd/lockd code use the inode returned by
file_inode(file) for lock manipulation. With Overlayfs, file_inode()
(the underlying inode) is not the same object as locks_inode() (the
overlay inode). This can result in "Leaked POSIX lock" messages
and eventually to a kernel crash as reported by Eddie Horng:
https://marc.info/?l=linux-unionfs&m=153086643202072&w=2
Fix all the call sites in nfsd/lockd that should use locks_inode().
This is a correctness bug that manifested when overlayfs gained
NFS export support in v4.16.
Reported-by: Eddie Horng <eddiehorng.tw@gmail.com>
Tested-by: Eddie Horng <eddiehorng.tw@gmail.com>
Cc: Jeff Layton <jlayton@kernel.org>
Fixes: 8383f1748829 ("ovl: wire up NFS export operations")
Cc: stable@vger.kernel.org
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'fs/lockd/clntproc.c')
| -rw-r--r-- | fs/lockd/clntproc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c index a2c0dfc6fdc0..d20b92f271c2 100644 --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -128,7 +128,7 @@ static void nlmclnt_setlockargs(struct nlm_rqst *req, struct file_lock *fl) char *nodename = req->a_host->h_rpcclnt->cl_nodename; nlmclnt_next_cookie(&argp->cookie); - memcpy(&lock->fh, NFS_FH(file_inode(fl->fl_file)), sizeof(struct nfs_fh)); + memcpy(&lock->fh, NFS_FH(locks_inode(fl->fl_file)), sizeof(struct nfs_fh)); lock->caller = nodename; lock->oh.data = req->a_owner; lock->oh.len = snprintf(req->a_owner, sizeof(req->a_owner), "%u@%s", |