NFS: Fix access to suid/sgid executables
nfs_open_permission_mask() should only check MAY_EXEC for files that
are opened with __FMODE_EXEC.
Also fix NFSv4 access-in-open path in a similar way -- openflags must be
used because fmode will not always have FMODE_EXEC set.
This patch fixes https://bugzilla.kernel.org/show_bug.cgi?id=49101
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 32e6c53..1b2d7eb 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2153,12 +2153,16 @@
{
int mask = 0;
- if ((openflags & O_ACCMODE) != O_WRONLY)
- mask |= MAY_READ;
- if ((openflags & O_ACCMODE) != O_RDONLY)
- mask |= MAY_WRITE;
- if (openflags & __FMODE_EXEC)
- mask |= MAY_EXEC;
+ if (openflags & __FMODE_EXEC) {
+ /* ONLY check exec rights */
+ mask = MAY_EXEC;
+ } else {
+ if ((openflags & O_ACCMODE) != O_WRONLY)
+ mask |= MAY_READ;
+ if ((openflags & O_ACCMODE) != O_RDONLY)
+ mask |= MAY_WRITE;
+ }
+
return mask;
}