发布于3月6日3月6日 Members Rocky Linux: CVE-2024-39276: kernel-rt (Multiple Advisories) Severity 4 CVSS (AV:L/AC:M/Au:N/C:P/I:P/A:P) Published 06/25/2024 Created 08/23/2024 Added 08/22/2024 Modified 11/18/2024 Description In the Linux kernel, the following vulnerability has been resolved: ext4: fix mb_cache_entry's e_refcnt leak in ext4_xattr_block_cache_find() Syzbot reports a warning as follows: ============================================ WARNING: CPU: 0 PID: 5075 at fs/mbcache.c:419 mb_cache_destroy+0x224/0x290 Modules linked in: CPU: 0 PID: 5075 Comm: syz-executor199 Not tainted 6.9.0-rc6-gb947cc5bf6d7 RIP: 0010:mb_cache_destroy+0x224/0x290 fs/mbcache.c:419 Call Trace: <TASK> ext4_put_super+0x6d4/0xcd0 fs/ext4/super.c:1375 generic_shutdown_super+0x136/0x2d0 fs/super.c:641 kill_block_super+0x44/0x90 fs/super.c:1675 ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7327 [...] ============================================ This is because when finding an entry in ext4_xattr_block_cache_find(), if ext4_sb_bread() returns -ENOMEM, the ce's e_refcnt, which has already grown in the __entry_find(), won't be put away, and eventually trigger the above issue in mb_cache_destroy() due to reference count leakage. So call mb_cache_entry_put() on the -ENOMEM error branch as a quick fix. Solution(s) rocky-upgrade-bpftool rocky-upgrade-bpftool-debuginfo rocky-upgrade-kernel rocky-upgrade-kernel-core rocky-upgrade-kernel-cross-headers rocky-upgrade-kernel-debug rocky-upgrade-kernel-debug-core rocky-upgrade-kernel-debug-debuginfo rocky-upgrade-kernel-debug-devel rocky-upgrade-kernel-debug-modules rocky-upgrade-kernel-debug-modules-extra rocky-upgrade-kernel-debuginfo rocky-upgrade-kernel-debuginfo-common-x86_64 rocky-upgrade-kernel-devel rocky-upgrade-kernel-headers rocky-upgrade-kernel-modules rocky-upgrade-kernel-modules-extra rocky-upgrade-kernel-rt rocky-upgrade-kernel-rt-core rocky-upgrade-kernel-rt-debug rocky-upgrade-kernel-rt-debug-core rocky-upgrade-kernel-rt-debug-debuginfo rocky-upgrade-kernel-rt-debug-devel rocky-upgrade-kernel-rt-debug-kvm rocky-upgrade-kernel-rt-debug-modules rocky-upgrade-kernel-rt-debug-modules-extra rocky-upgrade-kernel-rt-debuginfo rocky-upgrade-kernel-rt-debuginfo-common-x86_64 rocky-upgrade-kernel-rt-devel rocky-upgrade-kernel-rt-kvm rocky-upgrade-kernel-rt-modules rocky-upgrade-kernel-rt-modules-extra rocky-upgrade-kernel-tools rocky-upgrade-kernel-tools-debuginfo rocky-upgrade-kernel-tools-libs rocky-upgrade-kernel-tools-libs-devel rocky-upgrade-perf rocky-upgrade-perf-debuginfo rocky-upgrade-python3-perf rocky-upgrade-python3-perf-debuginfo References https://attackerkb.com/topics/cve-2024-39276 CVE - 2024-39276 https://errata.rockylinux.org/RLSA-2024:5101 https://errata.rockylinux.org/RLSA-2024:5102