From 44aa91ab2bb862540daa81403a1bc507496260fe Mon Sep 17 00:00:00 2001 From: Govindarajulu Varadarajan <_govind@gmx.com> Date: Thu, 6 Nov 2014 15:21:38 +0530 Subject: [PATCH] enic: handle error condition properly in enic_rq_indicate_buf In case of error in rx path, we free the buf->os_buf but we do not make it NULL. In next iteration we use the skb which is already freed. This causes the following crash. [ 886.154772] general protection fault: 0000 [#1] PREEMPT SMP [ 886.154851] Modules linked in: rpcsec_gss_krb5 auth_rpcgss oid_registry nfsv4 microcode evdev cirrus ttm drm_kms_helper drm enic syscopyarea sysfillrect sysimgblt psmouse i2c_piix4 serio_raw pcspkr i2c_core nfs lockd grace sunrpc fscache ext4 crc16 mbcache jbd2 sd_mod crc_t10dif crct10dif_common ata_generic ata_piix virtio_balloon libata scsi_mod uhci_hcd usbcore virtio_pci virtio_ring virtio usb_common [ 886.155199] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 3.17.0-netnext-05668-g876bc7f #272 [ 886.155263] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 886.155304] task: ffffffff81a1d580 ti: ffffffff81a00000 task.ti: ffffffff81a00000 [ 886.155356] RIP: 0010:[] [] kfree_skb_list+0x10/0x30 [ 886.155418] RSP: 0018:ffff880210603d48 EFLAGS: 00010206 [ 886.155456] RAX: 0000000000000020 RBX: 0000000000000000 RCX: 0000000000000000 [ 886.155504] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 004500084e000017 [ 886.155553] RBP: ffff880210603d50 R08: 00000000fe13d1b6 R09: 0000000000000001 [ 886.155601] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880209ff2f00 [ 886.155650] R13: ffff88020ac0fe40 R14: ffff880209ff2f00 R15: ffff8800da8e3a80 [ 886.155699] FS: 0000000000000000(0000) GS:ffff880210600000(0000) knlGS:0000000000000000 [ 886.155774] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 886.155814] CR2: 00007f0e0c925000 CR3: 0000000035e8b000 CR4: 00000000000006f0 [ 886.155865] Stack: [ 886.155882] 0000000000000000 ffff880210603d78 ffffffff81383f79 ffff880209ff2f00 [ 886.155942] ffff88020b0c0b40 000000000000c000 ffff880210603d90 ffffffff81383faf [ 886.156001] ffff880209ff2f00 ffff880210603da8 ffffffff8138406d ffff88020b1b08c0 [ 886.156061] Call Trace: [ 886.156080] [ 886.156095] [ 886.156112] [] skb_release_data+0xa9/0xc0 [ 886.157656] [] skb_release_all+0x1f/0x30 [ 886.159195] [] consume_skb+0x1d/0x40 [ 886.160719] [] __dev_kfree_skb_any+0x35/0x40 [ 886.162224] [] enic_rq_service.constprop.47+0xe5/0x5a0 [enic] [ 886.163756] [] enic_poll_msix_rq+0x199/0x370 [enic] [ 886.164730] [] net_rx_action+0x139/0x210 [ 886.164730] [] __do_softirq+0x14e/0x280 [ 886.164730] [] irq_exit+0x8e/0xb0 [ 886.164730] [] do_IRQ+0x5d/0x100 [ 886.164730] [] common_interrupt+0x72/0x72 fixes: a03bb56e67c357980dae886683733dab5583dc14 ("enic: implement rx_copybreak") Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com> Signed-off-by: David S. Miller --- drivers/net/ethernet/cisco/enic/enic_main.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c index 180e53fa628f..cd254d1ebd16 100644 --- a/drivers/net/ethernet/cisco/enic/enic_main.c +++ b/drivers/net/ethernet/cisco/enic/enic_main.c @@ -1037,7 +1037,10 @@ static void enic_rq_indicate_buf(struct vnic_rq *rq, enic->rq_truncated_pkts++; } + pci_unmap_single(enic->pdev, buf->dma_addr, buf->len, + PCI_DMA_FROMDEVICE); dev_kfree_skb_any(skb); + buf->os_buf = NULL; return; } @@ -1088,7 +1091,10 @@ static void enic_rq_indicate_buf(struct vnic_rq *rq, /* Buffer overflow */ + pci_unmap_single(enic->pdev, buf->dma_addr, buf->len, + PCI_DMA_FROMDEVICE); dev_kfree_skb_any(skb); + buf->os_buf = NULL; } } -- GitLab