| Message ID | 20151026164637.GK10039@oracle.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On 10/26/2015 9:46 AM, Sowmini Varadhan wrote: > > Either of pskb_pull() or pskb_trim() may fail under low memory conditions. > If rds_tcp_data_recv() ignores such failures, the application will > receive corrupted data because the skb has not been correctly > carved to the RDS datagram size. > > Avoid this by handling pskb_pull/pskb_trim failure in the same > manner as the skb_clone failure: bail out of rds_tcp_data_recv(), and > retry via the deferred call to rds_send_worker() that gets set up on > ENOMEM from rds_tcp_read_sock() > > Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> > --- Good one. Probably we should get this fix in stable versions as well. It seems to be applicable for all v2.6.32+ stable versions. FWIW, Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Regards, Santosh -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Sowmini Varadhan <sowmini.varadhan@oracle.com> Date: Mon, 26 Oct 2015 12:46:37 -0400 > Either of pskb_pull() or pskb_trim() may fail under low memory conditions. > If rds_tcp_data_recv() ignores such failures, the application will > receive corrupted data because the skb has not been correctly > carved to the RDS datagram size. > > Avoid this by handling pskb_pull/pskb_trim failure in the same > manner as the skb_clone failure: bail out of rds_tcp_data_recv(), and > retry via the deferred call to rds_send_worker() that gets set up on > ENOMEM from rds_tcp_read_sock() > > Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Applied and queued up for -stable, thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/rds/tcp_recv.c b/net/rds/tcp_recv.c index fbc5ef8..27a9921 100644 --- a/net/rds/tcp_recv.c +++ b/net/rds/tcp_recv.c @@ -214,8 +214,15 @@ static int rds_tcp_data_recv(read_descriptor_t *desc, struct sk_buff *skb, } to_copy = min(tc->t_tinc_data_rem, left); - pskb_pull(clone, offset); - pskb_trim(clone, to_copy); + if (!pskb_pull(clone, offset) || + pskb_trim(clone, to_copy)) { + pr_warn("rds_tcp_data_recv: pull/trim failed " + "left %zu data_rem %zu skb_len %d\n", + left, tc->t_tinc_data_rem, skb->len); + kfree_skb(clone); + desc->error = -ENOMEM; + goto out; + } skb_queue_tail(&tinc->ti_skb_list, clone); rdsdebug("skb %p data %p len %d off %u to_copy %zu -> "
Either of pskb_pull() or pskb_trim() may fail under low memory conditions. If rds_tcp_data_recv() ignores such failures, the application will receive corrupted data because the skb has not been correctly carved to the RDS datagram size. Avoid this by handling pskb_pull/pskb_trim failure in the same manner as the skb_clone failure: bail out of rds_tcp_data_recv(), and retry via the deferred call to rds_send_worker() that gets set up on ENOMEM from rds_tcp_read_sock() Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> --- net/rds/tcp_recv.c | 11 +++++++++-- 1 files changed, 9 insertions(+), 2 deletions(-)