From: ChenXiaoSong chenxiaosong2@huawei.com
[ Upstream commit ab0fc21bc7105b54bafd85bd8b82742f9e68898a ]
This reverts commit 44942b4e457beda00981f616402a1a791e8c616e.
After secondly opening a file with O_ACCMODE|O_DIRECT flags, nfs4_valid_open_stateid() will dereference NULL nfs4_state when lseek().
Reproducer: 1. mount -t nfs -o vers=4.2 $server_ip:/ /mnt/ 2. fd = open("/mnt/file", O_ACCMODE|O_DIRECT|O_CREAT) 3. close(fd) 4. fd = open("/mnt/file", O_ACCMODE|O_DIRECT) 5. lseek(fd)
Reported-by: Lyu Tao tao.lyu@epfl.ch Signed-off-by: ChenXiaoSong chenxiaosong2@huawei.com Signed-off-by: Trond Myklebust trond.myklebust@hammerspace.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfs/inode.c | 1 - fs/nfs/nfs4file.c | 2 +- 2 files changed, 1 insertion(+), 2 deletions(-)
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index a09d3ff627c2..4da8a4a7bad7 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -1180,7 +1180,6 @@ int nfs_open(struct inode *inode, struct file *filp) nfs_fscache_open_file(inode, filp); return 0; } -EXPORT_SYMBOL_GPL(nfs_open);
/* * This function is called whenever some part of NFS notices that diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index e79ae4cbc395..c178db86a6e8 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -51,7 +51,7 @@ nfs4_file_open(struct inode *inode, struct file *filp) return err;
if ((openflags & O_ACCMODE) == 3) - return nfs_open(inode, filp); + openflags--;
/* We can't create new files here */ openflags &= ~(O_CREAT|O_EXCL);