From: Jeff Layton jlayton@kernel.org
[ Upstream commit d53d70084d27f56bcdf5074328f2c9ec861be596 ]
notify_change can modify the iattr structure. In particular it can end up setting ATTR_MODE when ATTR_KILL_SUID is already set, causing a BUG() if the same iattr is passed to notify_change more than once.
Make a copy of the struct iattr before calling notify_change.
Reported-by: Zhi Li yieli@redhat.com Link: https://bugzilla.redhat.com/show_bug.cgi?id=2207969 Tested-by: Zhi Li yieli@redhat.com Fixes: 34b91dda7124 ("NFSD: Make nfsd4_setattr() wait before returning NFS4ERR_DELAY") Signed-off-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/vfs.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 5783209f17fc5..e4884dde048ce 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -536,7 +536,15 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp,
inode_lock(inode); for (retries = 1;;) { - host_err = __nfsd_setattr(dentry, iap); + struct iattr attrs; + + /* + * notify_change() can alter its iattr argument, making + * @iap unsuitable for submission multiple times. Make a + * copy for every loop iteration. + */ + attrs = *iap; + host_err = __nfsd_setattr(dentry, &attrs); if (host_err != -EAGAIN || !retries--) break; if (!nfsd_wait_for_delegreturn(rqstp, inode))