Re: [PATCH net-next 3/4] net/smc: fix one NULL pointer dereference in smc_ib_is_sg_need_sync()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





On 2024/8/9 16:31, Liu Jian wrote:
BUG: kernel NULL pointer dereference, address: 0000000000000238
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 3 PID: 289 Comm: kworker/3:1 Kdump: loaded Tainted: G           OE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
Workqueue: smc_hs_wq smc_listen_work [smc]
RIP: 0010:dma_need_sync+0x5/0x60
...
Call Trace:
  <TASK>
  ? dma_need_sync+0x5/0x60
  ? smc_ib_is_sg_need_sync+0x61/0xf0 [smc]
  smcr_buf_map_link+0x24a/0x380 [smc]
  __smc_buf_create+0x483/0xb10 [smc]
  smc_buf_create+0x21/0xe0 [smc]
  smc_listen_work+0xf11/0x14f0 [smc]
  ? smc_tcp_listen_work+0x364/0x520 [smc]
  process_one_work+0x18d/0x3f0
  worker_thread+0x304/0x440
  kthread+0xe4/0x110
  ret_from_fork+0x47/0x70
  ret_from_fork_asm+0x1a/0x30
  </TASK>

If the software RoCE device is used, ibdev->dma_device is a null pointer.
As a result, the problem occurs. Null pointer detection is added to
prevent problems.

Signed-off-by: Liu Jian <liujian56@xxxxxxxxxx>
---
  net/smc/smc_ib.c | 2 ++
  1 file changed, 2 insertions(+)

diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c
index 382351ac9434..059822cc3fde 100644
--- a/net/smc/smc_ib.c
+++ b/net/smc/smc_ib.c
@@ -748,6 +748,8 @@ bool smc_ib_is_sg_need_sync(struct smc_link *lnk,
  		    buf_slot->sgt[lnk->link_idx].nents, i) {
  		if (!sg_dma_len(sg))
  			break;
+		if (!lnk->smcibdev->ibdev->dma_device)
+			break;

LGTM.

Reviewed-by: Wen Gu <guwen@xxxxxxxxxxxxxxxxx>

  		if (dma_need_sync(lnk->smcibdev->ibdev->dma_device,
  				  sg_dma_address(sg))) {
  			ret = true;




[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Kernel Development]     [Kernel Newbies]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite Info]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Samba]     [Linux Media]     [Device Mapper]

  Powered by Linux