Commit efc21d95 authored Mar 14, 2016 by Arnd Bergmann Committed by David S. Miller Mar 14, 2016

vmxnet3: fix lock imbalance in vmxnet3_tq_xmit()

A recent bug fix rearranged the code in vmxnet3_tq_xmit() in a
way that left the error handling for oversized headers unlock
a lock that had not been taken yet. Gcc warns about the incorrect
use of the 'flags' variable because of that:

drivers/net/vmxnet3/vmxnet3_drv.c: In function 'vmxnet3_tq_xmit.constprop':
include/linux/spinlock.h:246:3: error: 'flags' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This changes the error handling path to 'goto' the end of the function
beyond the lock/unlock pair.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: cec05562 ("vmxnet3: avoid calling pskb_may_pull with interrupts disabled")
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 888506a9

drivers/net/vmxnet3/vmxnet3_drv.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -1022,14 +1022,16 @@ vmxnet3_tq_xmit(struct sk_buff skb, struct vmxnet3_tx_queue tq,
		if (ctx.mss) {
		if (unlikely(ctx.eth_ip_hdr_size + ctx.l4_hdr_size >
		VMXNET3_MAX_TX_BUF_SIZE)) {
		goto hdr_too_big;
		tq->stats.drop_oversized_hdr++;
		goto drop_pkt;
		}
		} else {
		if (skb->ip_summed == CHECKSUM_PARTIAL) {
		if (unlikely(ctx.eth_ip_hdr_size +
		skb->csum_offset >
		VMXNET3_MAX_CSUM_OFFSET)) {
		goto hdr_too_big;
		tq->stats.drop_oversized_hdr++;
		goto drop_pkt;
		}
		}
		}
		@@ -1123,8 +1125,6 @@ vmxnet3_tq_xmit(struct sk_buff skb, struct vmxnet3_tx_queue tq,

		return NETDEV_TX_OK;

		hdr_too_big:
		tq->stats.drop_oversized_hdr++;
		unlock_drop_pkt:
		spin_unlock_irqrestore(&tq->tx_lock, flags);
		drop_pkt: