Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: net/smc: Transitional solution for clcsock race issue We encountered a crash in smc_setsockopt() and it is caused by accessing smc->clcsock after clcsock was released. BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 PID: 50309 Comm: nginx Kdump: loaded Tainted: G E 5.16.0-rc4+ #53 RIP: 0010:smc_setsockopt+0x59/0x280 [smc] Call Trace: <TASK> __sys_setsockopt+0xfc/0x190 __x64_sys_setsockopt+0x20/0x30 do_syscall_64+0x34/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f16ba83918e </TASK> This patch tries to fix it by holding clcsock_release_lock and checking whether clcsock has already been released before access. In case that a crash of the same reason happens in smc_getsockopt() or smc_switch_to_fallback(), this patch also checkes smc->clcsock in them too. And the caller of smc_switch_to_fallback() will identify whether fallback succeeds according to the return value.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected fd57770dd198f5b2ddd5b9e6bf282cf98d63adb9 before 38f0bdd548fd2ef5d481b88d8a2bfef968452e34; affected fd57770dd198f5b2ddd5b9e6bf282cf98d63adb9 before 4284225cd8001e134f5cf533a7cd244bbb654d0f; affected fd57770dd198f5b2ddd5b9e6bf282cf98d63adb9 before c0bf3d8a943b6f2e912b7c1de03e2ef28e76f760; affected d1d004585b40c212b338fc8a40cbaaf230ea4703; affected 4.19.299 before 4.20 |
| Linux / Linux | affected 5.1; unaffected 0 before 5.1; unaffected 5.15.19 through 5.15.*; unaffected 5.16.5 through 5.16.*; unaffected 5.17 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/38f0bdd548fd2ef5d481b88d8a2bfef968452e34
- https://git.kernel.org/stable/c/4284225cd8001e134f5cf533a7cd244bbb654d0f
- https://git.kernel.org/stable/c/c0bf3d8a943b6f2e912b7c1de03e2ef28e76f760
ADP enrichment
No English description supplied.
No English description supplied.
No references supplied.