Description
In the Linux kernel, the following vulnerability has been resolved: kcm: Fix error handling for SOCK_DGRAM in kcm_sendmsg(). syzkaller found a memory leak in kcm_sendmsg(), and commit c821a88bd720 ("kcm: Fix memory leak in error path of kcm_sendmsg()") suppressed it by updating kcm_tx_msg(head)->last_skb if partial data is copied so that the following sendmsg() will resume from the skb. However, we cannot know how many bytes were copied when we get the error. Thus, we could mess up the MSG_MORE queue. When kcm_sendmsg() fails for SOCK_DGRAM, we should purge the queue as we do so for UDP by udp_flush_pending_frames(). Even without this change, when the error occurred, the following sendmsg() resumed from a wrong skb and the queue was messed up. However, we have yet to get such a report, and only syzkaller stumbled on it. So, this can be changed safely. Note this does not change SOCK_SEQPACKET behaviour.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
ab7ac4eb9832e32a09f4e8042705484d2fb0aad3 to < 21b467735b0888a8daa048f83d3b9b50fdab71ceaffectedab7ac4eb9832e32a09f4e8042705484d2fb0aad3 to < d4b8f380b0a041ee6a84fdac14127d8fe1dcad7baffectedab7ac4eb9832e32a09f4e8042705484d2fb0aad3 to < 1ce8362b4ac6b8e65fd04a22ea37ec776ee1ec5baffectedab7ac4eb9832e32a09f4e8042705484d2fb0aad3 to < 2e18493c421428a936946c452461b8e979088f17affectedab7ac4eb9832e32a09f4e8042705484d2fb0aad3 to < 55d2e7c1ab8eaa7b62575b8a4194132795d1f9fcaffectedab7ac4eb9832e32a09f4e8042705484d2fb0aad3 to < e5b28ce127a690f3acc49a6a342e6c9442c9edd6affectedab7ac4eb9832e32a09f4e8042705484d2fb0aad3 to < 992b2ac783aad360b98ed9d4686e86176a20f6f1affectedab7ac4eb9832e32a09f4e8042705484d2fb0aad3 to < a22730b1b4bf437c6bbfdeff5feddf54be4aeadaaffected
Linux Linux
Default version status: affected
4.6affected0 to < 4.6unaffected4.14.326 to ≤ 4.14.*unaffected4.19.295 to ≤ 4.19.*unaffected5.4.257 to ≤ 5.4.*unaffected5.10.195 to ≤ 5.10.*unaffected5.15.132 to ≤ 5.15.*unaffected6.1.54 to ≤ 6.1.*unaffected6.5.4 to ≤ 6.5.*unaffected6.6 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/21b467735b0888a8daa048f83d3b9b50fdab71ce ↗
- https://git.kernel.org/stable/c/d4b8f380b0a041ee6a84fdac14127d8fe1dcad7b ↗
- https://git.kernel.org/stable/c/1ce8362b4ac6b8e65fd04a22ea37ec776ee1ec5b ↗
- https://git.kernel.org/stable/c/2e18493c421428a936946c452461b8e979088f17 ↗
- https://git.kernel.org/stable/c/55d2e7c1ab8eaa7b62575b8a4194132795d1f9fc ↗
- https://git.kernel.org/stable/c/e5b28ce127a690f3acc49a6a342e6c9442c9edd6 ↗
- https://git.kernel.org/stable/c/992b2ac783aad360b98ed9d4686e86176a20f6f1 ↗
- https://git.kernel.org/stable/c/a22730b1b4bf437c6bbfdeff5feddf54be4aeada ↗