NFSv4: fix getacl ERANGE for some ACL buffer sizes

commit ed92d8c137b7794c2c2aa14479298b9885967607 upstream.

We're not taking into account that the space needed for the (variable
length) attr bitmap, with the result that we'd sometimes get a spurious
ERANGE when the ACL data got close to the end of a page.

Just add in an extra page to make sure.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Weston Andros Adamson 2017-02-23 14:54:21 -05:00 committed by Greg Kroah-Hartman
parent 5d23e89065
commit a0378b5bfc

View file

@ -4711,7 +4711,7 @@ out:
*/
static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t buflen)
{
struct page *pages[NFS4ACL_MAXPAGES] = {NULL, };
struct page *pages[NFS4ACL_MAXPAGES + 1] = {NULL, };
struct nfs_getaclargs args = {
.fh = NFS_FH(inode),
.acl_pages = pages,
@ -4725,13 +4725,9 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu
.rpc_argp = &args,
.rpc_resp = &res,
};
unsigned int npages = DIV_ROUND_UP(buflen, PAGE_SIZE);
unsigned int npages = DIV_ROUND_UP(buflen, PAGE_SIZE) + 1;
int ret = -ENOMEM, i;
/* As long as we're doing a round trip to the server anyway,
* let's be prepared for a page of acl data. */
if (npages == 0)
npages = 1;
if (npages > ARRAY_SIZE(pages))
return -ERANGE;