| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-36979: net: bridge: mst: fix vlan use-after-free |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net: bridge: mst: fix vlan use-after-free |
| |
| syzbot reported a suspicious rcu usage[1] in bridge's mst code. While |
| fixing it I noticed that nothing prevents a vlan to be freed while |
| walking the list from the same path (br forward delay timer). Fix the rcu |
| usage and also make sure we are not accessing freed memory by making |
| br_mst_vlan_set_state use rcu read lock. |
| |
| [1] |
| WARNING: suspicious RCU usage |
| 6.9.0-rc6-syzkaller #0 Not tainted |
| ----------------------------- |
| net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage! |
| ... |
| stack backtrace: |
| CPU: 1 PID: 8017 Comm: syz-executor.1 Not tainted 6.9.0-rc6-syzkaller #0 |
| Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 |
| Call Trace: |
| <IRQ> |
| __dump_stack lib/dump_stack.c:88 [inline] |
| dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 |
| lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712 |
| nbp_vlan_group net/bridge/br_private.h:1599 [inline] |
| br_mst_set_state+0x1ea/0x650 net/bridge/br_mst.c:105 |
| br_set_state+0x28a/0x7b0 net/bridge/br_stp.c:47 |
| br_forward_delay_timer_expired+0x176/0x440 net/bridge/br_stp_timer.c:88 |
| call_timer_fn+0x18e/0x650 kernel/time/timer.c:1793 |
| expire_timers kernel/time/timer.c:1844 [inline] |
| __run_timers kernel/time/timer.c:2418 [inline] |
| __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2429 |
| run_timer_base kernel/time/timer.c:2438 [inline] |
| run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2448 |
| __do_softirq+0x2c6/0x980 kernel/softirq.c:554 |
| invoke_softirq kernel/softirq.c:428 [inline] |
| __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 |
| irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 |
| instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] |
| sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 |
| </IRQ> |
| <TASK> |
| asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 |
| RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758 |
| Code: 2b 00 74 08 4c 89 f7 e8 ba d1 84 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 |
| RSP: 0018:ffffc90013657100 EFLAGS: 00000206 |
| RAX: 0000000000000001 RBX: 1ffff920026cae2c RCX: 0000000000000001 |
| RDX: dffffc0000000000 RSI: ffffffff8bcaca00 RDI: ffffffff8c1eaa60 |
| RBP: ffffc90013657260 R08: ffffffff92efe507 R09: 1ffffffff25dfca0 |
| R10: dffffc0000000000 R11: fffffbfff25dfca1 R12: 1ffff920026cae28 |
| R13: dffffc0000000000 R14: ffffc90013657160 R15: 0000000000000246 |
| |
| The Linux kernel CVE team has assigned CVE-2024-36979 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.18 with commit ec7328b59176227216c461601c6bd0e922232a9b and fixed in 6.1.93 with commit 8ca9a750fc711911ef616ceb627d07357b04545e |
| Issue introduced in 5.18 with commit ec7328b59176227216c461601c6bd0e922232a9b and fixed in 6.6.33 with commit 4488617e5e995a09abe4d81add5fb165674edb59 |
| Issue introduced in 5.18 with commit ec7328b59176227216c461601c6bd0e922232a9b and fixed in 6.8.12 with commit a2b01e65d9ba8af2bb086d3b7288ca53a07249ac |
| Issue introduced in 5.18 with commit ec7328b59176227216c461601c6bd0e922232a9b and fixed in 6.9.3 with commit e43dd2b1ec746e105b7db5f9ad6ef14685a615a4 |
| Issue introduced in 5.18 with commit ec7328b59176227216c461601c6bd0e922232a9b and fixed in 6.10 with commit 3a7c1661ae1383364cd6092d851f5e5da64d476b |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-36979 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| net/bridge/br_mst.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/8ca9a750fc711911ef616ceb627d07357b04545e |
| https://git.kernel.org/stable/c/4488617e5e995a09abe4d81add5fb165674edb59 |
| https://git.kernel.org/stable/c/a2b01e65d9ba8af2bb086d3b7288ca53a07249ac |
| https://git.kernel.org/stable/c/e43dd2b1ec746e105b7db5f9ad6ef14685a615a4 |
| https://git.kernel.org/stable/c/3a7c1661ae1383364cd6092d851f5e5da64d476b |
