Improper Input Validation The advisory has been revoked - it doesn't affect any version of package kernel-selftests-internal  (opens in a new tab)

The Red Hat security team deemed this advisory irrelevant for RHEL:8.

Note: Versions mentioned in the description apply only to the upstream kernel-selftests-internal package and not the kernel-selftests-internal package as distributed by RHEL.

In the Linux kernel, the following vulnerability has been resolved:

tipc: fix kernel warning when sending SYN message

When sending a SYN message, this kernel stack trace is observed:

... [ 13.396352] RIP: 0010:_copy_from_iter+0xb4/0x550 ... [ 13.398494] Call Trace: [ 13.398630] <TASK> [ 13.398630] ? __alloc_skb+0xed/0x1a0 [ 13.398630] tipc_msg_build+0x12c/0x670 [tipc] [ 13.398630] ? shmem_add_to_page_cache.isra.71+0x151/0x290 [ 13.398630] __tipc_sendmsg+0x2d1/0x710 [tipc] [ 13.398630] ? tipc_connect+0x1d9/0x230 [tipc] [ 13.398630] ? __local_bh_enable_ip+0x37/0x80 [ 13.398630] tipc_connect+0x1d9/0x230 [tipc] [ 13.398630] ? __sys_connect+0x9f/0xd0 [ 13.398630] __sys_connect+0x9f/0xd0 [ 13.398630] ? preempt_count_add+0x4d/0xa0 [ 13.398630] ? fpregs_assert_state_consistent+0x22/0x50 [ 13.398630] __x64_sys_connect+0x16/0x20 [ 13.398630] do_syscall_64+0x42/0x90 [ 13.398630] entry_SYSCALL_64_after_hwframe+0x63/0xcd

It is because commit a41dad905e5a ("iov_iter: saner checks for attempt to copy to/from iterator") has introduced sanity check for copying from/to iov iterator. Lacking of copy direction from the iterator viewpoint would lead to kernel stack trace like above.

This commit fixes this issue by initializing the iov iterator with the correct copy direction when sending SYN or ACK without data.

• https://access.redhat.com/security/cve/CVE-2023-52700
• https://git.kernel.org/stable/c/11a4d6f67cf55883dc78e31c247d1903ed7feccc
• https://git.kernel.org/stable/c/54b6082aec178f16ad6d193b4ecdc9c4823d9a32