发布于3月6日3月6日 Members SUSE: CVE-2021-47249: SUSE Linux Security Advisory Severity 5 CVSS (AV:L/AC:L/Au:S/C:N/I:N/A:C) Published 05/21/2024 Created 08/16/2024 Added 08/09/2024 Modified 01/28/2025 Description In the Linux kernel, the following vulnerability has been resolved: net: rds: fix memory leak in rds_recvmsg Syzbot reported memory leak in rds. The problem was in unputted refcount in case of error. int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, int msg_flags) { ... if (!rds_next_incoming(rs, &inc)) { ... } After this "if" inc refcount incremented and if (rds_cmsg_recv(inc, msg, rs)) { ret = -EFAULT; goto out; } ... out: return ret; } in case of rds_cmsg_recv() fail the refcount won't be decremented. And it's easy to see from ftrace log, that rds_inc_addref() don't have rds_inc_put() pair in rds_recvmsg() after rds_cmsg_recv() 1) |rds_recvmsg() { 1) 3.721 us|rds_inc_addref(); 1) 3.853 us|rds_message_inc_copy_to_user(); 1) + 10.395 us |rds_cmsg_recv(); 1) + 34.260 us |} Solution(s) suse-upgrade-kernel-azure suse-upgrade-kernel-azure-base suse-upgrade-kernel-azure-devel suse-upgrade-kernel-default suse-upgrade-kernel-default-base suse-upgrade-kernel-default-devel suse-upgrade-kernel-default-extra suse-upgrade-kernel-default-man suse-upgrade-kernel-devel suse-upgrade-kernel-devel-azure suse-upgrade-kernel-docs suse-upgrade-kernel-macros suse-upgrade-kernel-obs-build suse-upgrade-kernel-source suse-upgrade-kernel-source-azure suse-upgrade-kernel-syms suse-upgrade-kernel-syms-azure References https://attackerkb.com/topics/cve-2021-47249 CVE - 2021-47249