From 44942b4e457beda00981f616402a1a791e8c616e Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 27 Jun 2019 06:41:45 -0400 Subject: [PATCH] NFSv4: Handle the special Linux file open access mode According to the open() manpage, Linux reserves the access mode 3 to mean "check for read and write permission on the file and return a file descriptor that can't be used for reading or writing." Currently, the NFSv4 code will ask the server to open the file, and will use an incorrect share access mode of 0. Since it has an incorrect share access mode, the client later forgets to send a corresponding close, meaning it can leak stateids on the server. Fixes: ce4ef7c0a8a05 ("NFS: Split out NFS v4 file operations") Cc: stable@vger.kernel.org # 3.6+ Signed-off-by: Trond Myklebust --- fs/nfs/inode.c | 1 + fs/nfs/nfs4file.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 0b4a1a974411..53777813ca95 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -1100,6 +1100,7 @@ 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 cf42a8b939e3..3a507c42c1ca 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -49,7 +49,7 @@ nfs4_file_open(struct inode *inode, struct file *filp) return err; if ((openflags & O_ACCMODE) == 3) - openflags--; + return nfs_open(inode, filp); /* We can't create new files here */ openflags &= ~(O_CREAT|O_EXCL); -- 2.45.2