NFSv4: Fix an Oops in the NFSv4 getacl code
Commit bf118a342f10dafe44b14451a1392c3254629a1f (NFSv4: include bitmap
in nfsv4 get acl data) introduces the 'acl_scratch' page for the case
where we may need to decode multi-page data. However it fails to take
into account the fact that the variable may be NULL (for the case where
we're not doing multi-page decode), and it also attaches it to the
encoding xdr_stream rather than the decoding one.
The immediate result is an Oops in nfs4_xdr_enc_getacl due to the
call to page_address() with a NULL page pointer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Andy Adamson <andros@netapp.com>
Cc: stable@vger.kernel.org
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 95e92e43..33bd8d0 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -2522,7 +2522,6 @@
xdr_inline_pages(&req->rq_rcv_buf, replen << 2,
args->acl_pages, args->acl_pgbase, args->acl_len);
- xdr_set_scratch_buffer(xdr, page_address(args->acl_scratch), PAGE_SIZE);
encode_nops(&hdr);
}
@@ -6032,6 +6031,10 @@
struct compound_hdr hdr;
int status;
+ if (res->acl_scratch != NULL) {
+ void *p = page_address(res->acl_scratch);
+ xdr_set_scratch_buffer(xdr, p, PAGE_SIZE);
+ }
status = decode_compound_hdr(xdr, &hdr);
if (status)
goto out;