CVE-2023-53110 Information

Description

In the Linux kernel the following vulnerability has been resolved:

net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()

When performing a stress test on SMC-R by rmmod mlx5_ib driver during the wrk/nginx test we found that there is a probability of triggering a panic while terminating all link groups.

This issue dues to the race between smc_smcr_terminate_all() and smc_buf_create().

		smc_smcr_terminate_all

smc_buf_create / init / conn->sndbuf_desc = NULL; …

		__smc_lgr_terminate
			smc_conn_kill
				smc_close_abort
					smc_cdc_get_slot_and_msg_send

		__softirqentry_text_start
			smc_wr_tx_process_cqe
				smc_cdc_tx_handler
					READ(conn->sndbuf_desc->len);
					/ panic dues to NULL sndbuf_desc /

conn->sndbuf_desc = xxx;

This patch tries to fix the issue by always to check the sndbuf_desc before send any cdc msg to make sure that no null pointer is seen during cqe processing.

Reference

https://git.kernel.org/stable/c/22a825c541d775c1dbe7b2402786025acad6727b https://git.kernel.org/stable/c/31817c530768b0199771ec6019571b4f0ddbf230 https://git.kernel.org/stable/c/3c270435db8aa34929263dddae8fd050f5216ecb https://git.kernel.org/stable/c/3ebac7cf0a184a8102821a7a00203f02bebda83c https://git.kernel.org/stable/c/b108bd9e6be000492ebebe867daa699285978a10