-stable review patch. If anyone has any objections, please let us know. ------------------ From: Frank Filz commit 7ee2cb7f32b299c2b06a31fde155457203e4b7dd upstream. 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 Tested-by: Eugene Teo Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/nfs/dir.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1925,7 +1925,8 @@ int nfs_permission(struct inode *inode, 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: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/