Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [ 22/47] nfsd4: fix oops on unusual readlike compound | Date | Wed, 9 Jan 2013 12:35:17 -0800 |
| |
3.0-stable review patch. If anyone has any objections, please let me know.
------------------
From: "J. Bruce Fields" <bfields@redhat.com>
commit d5f50b0c290431c65377c4afa1c764e2c3fe5305 upstream.
If the argument and reply together exceed the maximum payload size, then a reply with a read-like operation can overlow the rq_pages array.
Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- fs/nfsd/nfs4xdr.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
--- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2682,11 +2682,16 @@ nfsd4_encode_read(struct nfsd4_compoundr len = maxcount; v = 0; while (len > 0) { - pn = resp->rqstp->rq_resused++; + pn = resp->rqstp->rq_resused; + if (!resp->rqstp->rq_respages[pn]) { /* ran out of pages */ + maxcount -= len; + break; + } resp->rqstp->rq_vec[v].iov_base = page_address(resp->rqstp->rq_respages[pn]); resp->rqstp->rq_vec[v].iov_len = len < PAGE_SIZE ? len : PAGE_SIZE; + resp->rqstp->rq_resused++; v++; len -= PAGE_SIZE; } @@ -2734,6 +2739,8 @@ nfsd4_encode_readlink(struct nfsd4_compo return nfserr; if (resp->xbuf->page_len) return nfserr_resource; + if (!resp->rqstp->rq_respages[resp->rqstp->rq_resused]) + return nfserr_resource; page = page_address(resp->rqstp->rq_respages[resp->rqstp->rq_resused++]); @@ -2783,6 +2790,8 @@ nfsd4_encode_readdir(struct nfsd4_compou return nfserr; if (resp->xbuf->page_len) return nfserr_resource; + if (!resp->rqstp->rq_respages[resp->rqstp->rq_resused]) + return nfserr_resource; RESERVE_SPACE(8); /* verifier */ savep = p;
| |