From: Trond Myklebust VFS: Fix access("file", X_OK) in the presence of ACLs Currently, the access() call will return incorrect information on NFS if there exists an ACL that grants execute access to the user on a regular file. The reason the information is incorrect is that the VFS overrides this execute access in open_exec() by checking (inode->i_mode & 0111). This patch propagates the VFS execute bit check back into the generic permission() call. Signed-off-by: Trond Myklebust --- fs/namei.c | 9 ++++++++- 1 files changed, 8 insertions(+), 1 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 8631664..432d6bc 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -227,10 +227,10 @@ int generic_permission(struct inode *ino int permission(struct inode *inode, int mask, struct nameidata *nd) { + umode_t mode = inode->i_mode; int retval, submask; if (mask & MAY_WRITE) { - umode_t mode = inode->i_mode; /* * Nobody gets write access to a read-only fs. @@ -247,6 +247,13 @@ int permission(struct inode *inode, int } + /* + * MAY_EXEC on regular files requires special handling: We override + * filesystem execute permissions if the mode bits aren't set. + */ + if ((mask & MAY_EXEC) && S_ISREG(mode) && !(mode & S_IXUGO)) + return -EACCES; + /* Ordinary permission routines do not understand MAY_APPEND. */ submask = mask & ~MAY_APPEND; if (inode->i_op && inode->i_op->permission)