From: Sowmini Varadhan Date: Mon, 26 Oct 2015 16:46:37 +0000 (-0400) Subject: RDS-TCP: Recover correctly from pskb_pull()/pksb_trim() failure in rds_tcp_data_recv X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=8ce675ff39b9958d1c10f86cf58e357efaafc856;p=openwrt%2Fstaging%2Fblogic.git RDS-TCP: Recover correctly from pskb_pull()/pksb_trim() failure in rds_tcp_data_recv 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 Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller --- diff --git a/net/rds/tcp_recv.c b/net/rds/tcp_recv.c index fbc5ef88bc0e..27a992154804 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 -> "