From 5b362ac3799ff4225c40935500f520cad4d7ed66 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 10 Dec 2010 12:31:14 -0500 Subject: [PATCH] NFS: Fix panic after nfs_umount() After a few unsuccessful NFS mount attempts in which the client and server cannot agree on an authentication flavor both support, the client panics. nfs_umount() is invoked in the kernel in this case. Turns out nfs_umount()'s UMNT RPC invocation causes the RPC client to write off the end of the rpc_clnt's iostat array. This is because the mount client's nrprocs field is initialized with the count of defined procedures (two: MNT and UMNT), rather than the size of the client's proc array (four). The fix is to use the same initialization technique used by most other upper layer clients in the kernel. Introduced by commit 0b524123, which failed to update nrprocs when support was added for UMNT in the kernel. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=24302 BugLink: http://bugs.launchpad.net/bugs/683938 Reported-by: Stefan Bader Tested-by: Stefan Bader Cc: stable@kernel.org # >= 2.6.32 Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/mount_clnt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c index eceafe74f473..4f981f1f6689 100644 --- a/fs/nfs/mount_clnt.c +++ b/fs/nfs/mount_clnt.c @@ -505,13 +505,13 @@ static struct rpc_procinfo mnt3_procedures[] = { static struct rpc_version mnt_version1 = { .number = 1, - .nrprocs = 2, + .nrprocs = ARRAY_SIZE(mnt_procedures), .procs = mnt_procedures, }; static struct rpc_version mnt_version3 = { .number = 3, - .nrprocs = 2, + .nrprocs = ARRAY_SIZE(mnt3_procedures), .procs = mnt3_procedures, }; -- 2.20.1