From 7ee2cb7f32b299c2b06a31fde155457203e4b7dd Mon Sep 17 00:00:00 2001 From: Frank Filz Date: Mon, 18 May 2009 17:41:40 -0400 Subject: [PATCH] nfs: Fix NFS v4 client handling of MAY_EXEC in nfs_permission. The problem is that permission checking is skipped if atomic open is possible, but when exec opens a file, it just opens it O_READONLY which means EXEC permission will not be checked at that time. This problem is observed by the following sequence (executed as root): mount -t nfs4 server:/ /mnt4 echo "ls" >/mnt4/foo chmod 744 /mnt4/foo su guest -c "mnt4/foo" Signed-off-by: Frank Filz Signed-off-by: Trond Myklebust Cc: stable@kernel.org Tested-by: Eugene Teo Signed-off-by: Linus Torvalds --- fs/nfs/dir.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 370b190a09d1..89f98e9a024b 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1943,7 +1943,8 @@ int nfs_permission(struct inode *inode, int mask) case S_IFREG: /* NFSv4 has atomic_open... */ if (nfs_server_capable(inode, NFS_CAP_ATOMIC_OPEN) - && (mask & MAY_OPEN)) + && (mask & MAY_OPEN) + && !(mask & MAY_EXEC)) goto out; break; case S_IFDIR: -- 2.20.1