4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Benjamin Coddington bcodding@redhat.com
[ Upstream commit 4b09ec4b14a168bf2c687e1f598140c3c11e9222 ]
I have reports of a crash that look like __fput() was called twice for a NFSv4.0 file. It seems possible that the state manager could try to reclaim a lock and take a reference on the fl->fl_file at the same time the file is being released if, during the close(), a signal interrupts the wait for outstanding IO while removing locks which then skips the removal of that lock.
Since 83bfff23e9ed ("nfs4: have do_vfs_lock take an inode pointer") has removed the need to traverse fl->fl_file->f_inode in nfs4_lock_done(), taking that reference is no longer necessary.
Signed-off-by: Benjamin Coddington bcodding@redhat.com Reviewed-by: Jeff Layton jlayton@redhat.com Signed-off-by: Trond Myklebust trond.myklebust@primarydata.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfs/nfs4proc.c | 3 --- 1 file changed, 3 deletions(-)
--- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -38,7 +38,6 @@ #include <linux/mm.h> #include <linux/delay.h> #include <linux/errno.h> -#include <linux/file.h> #include <linux/string.h> #include <linux/ratelimit.h> #include <linux/printk.h> @@ -5738,7 +5737,6 @@ static struct nfs4_lockdata *nfs4_alloc_ p->server = server; atomic_inc(&lsp->ls_count); p->ctx = get_nfs_open_context(ctx); - get_file(fl->fl_file); memcpy(&p->fl, fl, sizeof(p->fl)); return p; out_free_seqid: @@ -5851,7 +5849,6 @@ static void nfs4_lock_release(void *call nfs_free_seqid(data->arg.lock_seqid); nfs4_put_lock_state(data->lsp); put_nfs_open_context(data->ctx); - fput(data->fl.fl_file); kfree(data); dprintk("%s: done!\n", __func__); }