tree 35bc3553ee76e4191bed00d9cb21379187375112
parent be79d7fa43f91c22e0e140c06aad57e9e5f417b2
author Arnd Bergmann <arnd@arndb.de> 1479847852 +0100
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1480666141 +0100

NFSv4.x: hide array-bounds warning

commit d55b352b01bc78fbc3d1bb650140668b87e58bf9 upstream.

A correct bugfix introduced a harmless warning that shows up with gcc-7:

fs/nfs/callback.c: In function 'nfs_callback_up':
fs/nfs/callback.c:214:14: error: array subscript is outside array bounds [-Werror=array-bounds]

What happens here is that the 'minorversion == 0' check tells the
compiler that we assume minorversion can be something other than 0,
but when CONFIG_NFS_V4_1 is disabled that would be invalid and
result in an out-of-bounds access.

The added check for IS_ENABLED(CONFIG_NFS_V4_1) tells gcc that this
really can't happen, which makes the code slightly smaller and also
avoids the warning.

The bugfix that introduced the warning is marked for stable backports,
we want this one backported to the same releases.

Fixes: 98b0f80c2396 ("NFSv4.x: Fix a refcount leak in nfs_callback_up_net")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>