In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix one NULL pointer dereference in smcibissgneed_sync()
BUG: kernel NULL pointer dereference, address: 00000000000002ec PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP PTI CPU: 28 UID: 0 PID: 343 Comm: kworker/28:1 Kdump: loaded Tainted: G OE 6.17.0-rc2+ #9 NONE Tainted: [O]=OOTMODULE, [E]=UNSIGNEDMODULE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 Workqueue: smchswq smclistenwork [smc] RIP: 0010:smcibissgneedsync+0x9e/0xd0 [smc] ... Call Trace: <TASK> smcrbufmaplink+0x211/0x2a0 [smc] _smcbufcreate+0x522/0x970 [smc] smcbufcreate+0x3a/0x110 [smc] smcfindrdmav2deviceserv+0x18f/0x240 [smc] ? smcvlanbytcpsk+0x7e/0xe0 [smc] smclistenfinddevice+0x1dd/0x2b0 [smc] smclistenwork+0x30f/0x580 [smc] processonework+0x18c/0x340 workerthread+0x242/0x360 kthread+0xe7/0x220 retfromfork+0x13a/0x160 retfromforkasm+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.