| 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-2024-26724: net/mlx5: DPLL, Fix possible use after free after delayed work timer triggers |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net/mlx5: DPLL, Fix possible use after free after delayed work timer triggers |
| |
| I managed to hit following use after free warning recently: |
| |
| [ 2169.711665] ================================================================== |
| [ 2169.714009] BUG: KASAN: slab-use-after-free in __run_timers.part.0+0x179/0x4c0 |
| [ 2169.716293] Write of size 8 at addr ffff88812b326a70 by task swapper/4/0 |
| |
| [ 2169.719022] CPU: 4 PID: 0 Comm: swapper/4 Not tainted 6.8.0-rc2jiri+ #2 |
| [ 2169.720974] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 |
| [ 2169.722457] Call Trace: |
| [ 2169.722756] <IRQ> |
| [ 2169.723024] dump_stack_lvl+0x58/0xb0 |
| [ 2169.723417] print_report+0xc5/0x630 |
| [ 2169.723807] ? __virt_addr_valid+0x126/0x2b0 |
| [ 2169.724268] kasan_report+0xbe/0xf0 |
| [ 2169.724667] ? __run_timers.part.0+0x179/0x4c0 |
| [ 2169.725116] ? __run_timers.part.0+0x179/0x4c0 |
| [ 2169.725570] __run_timers.part.0+0x179/0x4c0 |
| [ 2169.726003] ? call_timer_fn+0x320/0x320 |
| [ 2169.726404] ? lock_downgrade+0x3a0/0x3a0 |
| [ 2169.726820] ? kvm_clock_get_cycles+0x14/0x20 |
| [ 2169.727257] ? ktime_get+0x92/0x150 |
| [ 2169.727630] ? lapic_next_deadline+0x35/0x60 |
| [ 2169.728069] run_timer_softirq+0x40/0x80 |
| [ 2169.728475] __do_softirq+0x1a1/0x509 |
| [ 2169.728866] irq_exit_rcu+0x95/0xc0 |
| [ 2169.729241] sysvec_apic_timer_interrupt+0x6b/0x80 |
| [ 2169.729718] </IRQ> |
| [ 2169.729993] <TASK> |
| [ 2169.730259] asm_sysvec_apic_timer_interrupt+0x16/0x20 |
| [ 2169.730755] RIP: 0010:default_idle+0x13/0x20 |
| [ 2169.731190] Code: c0 08 00 00 00 4d 29 c8 4c 01 c7 4c 29 c2 e9 72 ff ff ff cc cc cc cc 8b 05 9a 7f 1f 02 85 c0 7e 07 0f 00 2d cf 69 43 00 fb f4 <fa> c3 66 66 2e 0f 1f 84 00 00 00 00 00 65 48 8b 04 25 c0 93 04 00 |
| [ 2169.732759] RSP: 0018:ffff888100dbfe10 EFLAGS: 00000242 |
| [ 2169.733264] RAX: 0000000000000001 RBX: ffff888100d9c200 RCX: ffffffff8241bd62 |
| [ 2169.733925] RDX: ffffed109a848b15 RSI: 0000000000000004 RDI: ffffffff8127ac55 |
| [ 2169.734566] RBP: 0000000000000004 R08: 0000000000000000 R09: ffffed109a848b14 |
| [ 2169.735200] R10: ffff8884d42458a3 R11: 000000000000ba7e R12: ffffffff83d7d3a0 |
| [ 2169.735835] R13: 1ffff110201b7fc6 R14: 0000000000000000 R15: ffff888100d9c200 |
| [ 2169.736478] ? ct_kernel_exit.constprop.0+0xa2/0xc0 |
| [ 2169.736954] ? do_idle+0x285/0x290 |
| [ 2169.737323] default_idle_call+0x63/0x90 |
| [ 2169.737730] do_idle+0x285/0x290 |
| [ 2169.738089] ? arch_cpu_idle_exit+0x30/0x30 |
| [ 2169.738511] ? mark_held_locks+0x1a/0x80 |
| [ 2169.738917] ? lockdep_hardirqs_on_prepare+0x12e/0x200 |
| [ 2169.739417] cpu_startup_entry+0x30/0x40 |
| [ 2169.739825] start_secondary+0x19a/0x1c0 |
| [ 2169.740229] ? set_cpu_sibling_map+0xbd0/0xbd0 |
| [ 2169.740673] secondary_startup_64_no_verify+0x15d/0x16b |
| [ 2169.741179] </TASK> |
| |
| [ 2169.741686] Allocated by task 1098: |
| [ 2169.742058] kasan_save_stack+0x1c/0x40 |
| [ 2169.742456] kasan_save_track+0x10/0x30 |
| [ 2169.742852] __kasan_kmalloc+0x83/0x90 |
| [ 2169.743246] mlx5_dpll_probe+0xf5/0x3c0 [mlx5_dpll] |
| [ 2169.743730] auxiliary_bus_probe+0x62/0xb0 |
| [ 2169.744148] really_probe+0x127/0x590 |
| [ 2169.744534] __driver_probe_device+0xd2/0x200 |
| [ 2169.744973] device_driver_attach+0x6b/0xf0 |
| [ 2169.745402] bind_store+0x90/0xe0 |
| [ 2169.745761] kernfs_fop_write_iter+0x1df/0x2a0 |
| [ 2169.746210] vfs_write+0x41f/0x790 |
| [ 2169.746579] ksys_write+0xc7/0x160 |
| [ 2169.746947] do_syscall_64+0x6f/0x140 |
| [ 2169.747333] entry_SYSCALL_64_after_hwframe+0x46/0x4e |
| |
| [ 2169.748049] Freed by task 1220: |
| [ 2169.748393] kasan_save_stack+0x1c/0x40 |
| [ 2169.748789] kasan_save_track+0x10/0x30 |
| [ 2169.749188] kasan_save_free_info+0x3b/0x50 |
| [ 2169.749621] poison_slab_object+0x106/0x180 |
| [ 2169.750044] __kasan_slab_free+0x14/0x50 |
| [ 2169.750451] kfree+0x118/0x330 |
| [ 2169.750792] mlx5_dpll_remove+0xf5/0x110 [mlx5_dpll] |
| [ 2169.751271] auxiliary_bus_remove+0x2e/0x40 |
| [ 2169.751694] device_release_driver_internal+0x24b/0x2e0 |
| [ 2169.752191] unbind_store+0xa6/0xb0 |
| [ 2169.752563] kernfs_fop_write_iter+0x1df/0x2a0 |
| [ 2169.753004] vfs_write+0x41f/0x790 |
| [ 2169.753381] ksys_write+0xc7/0x160 |
| [ 2169.753750] do_syscall_64+0x6f/0x140 |
| [ 2169.754132] entry_SYSCALL_64_after_hwframe+0x46/0x4e |
| |
| [ 2169.754847] Last potentially related work creation: |
| [ 2169.755315] kasan_save_stack+0x1c/0x40 |
| [ 2169.755709] __kasan_record_aux_stack+0x9b/0xf0 |
| [ 2169.756165] __queue_work+0x382/0x8f0 |
| [ 2169.756552] call_timer_fn+0x126/0x320 |
| [ 2169.756941] __run_timers.part.0+0x2ea/0x4c0 |
| [ 2169.757376] run_timer_softirq+0x40/0x80 |
| [ 2169.757782] __do_softirq+0x1a1/0x509 |
| |
| [ 2169.758387] Second to last potentially related work creation: |
| [ 2169.758924] kasan_save_stack+0x1c/0x40 |
| [ 2169.759322] __kasan_record_aux_stack+0x9b/0xf0 |
| [ 2169.759773] __queue_work+0x382/0x8f0 |
| [ 2169.760156] call_timer_fn+0x126/0x320 |
| [ 2169.760550] __run_timers.part.0+0x2ea/0x4c0 |
| [ 2169.760978] run_timer_softirq+0x40/0x80 |
| [ 2169.761381] __do_softirq+0x1a1/0x509 |
| |
| [ 2169.761998] The buggy address belongs to the object at ffff88812b326a00 |
| which belongs to the cache kmalloc-256 of size 256 |
| [ 2169.763061] The buggy address is located 112 bytes inside of |
| freed 256-byte region [ffff88812b326a00, ffff88812b326b00) |
| |
| [ 2169.764346] The buggy address belongs to the physical page: |
| [ 2169.764866] page:000000000f2b1e89 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12b324 |
| [ 2169.765731] head:000000000f2b1e89 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 |
| [ 2169.766484] anon flags: 0x200000000000840(slab|head|node=0|zone=2) |
| [ 2169.767048] page_type: 0xffffffff() |
| [ 2169.767422] raw: 0200000000000840 ffff888100042b40 0000000000000000 dead000000000001 |
| [ 2169.768183] raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 |
| [ 2169.768899] page dumped because: kasan: bad access detected |
| |
| [ 2169.769649] Memory state around the buggy address: |
| [ 2169.770116] ffff88812b326900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc |
| [ 2169.770805] ffff88812b326980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc |
| [ 2169.771485] >ffff88812b326a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| [ 2169.772173] ^ |
| [ 2169.772787] ffff88812b326a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| [ 2169.773477] ffff88812b326b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc |
| [ 2169.774160] ================================================================== |
| [ 2169.774845] ================================================================== |
| |
| I didn't manage to reproduce it. Though the issue seems to be obvious. |
| There is a chance that the mlx5_dpll_remove() calls |
| cancel_delayed_work() when the work runs and manages to re-arm itself. |
| In that case, after delay timer triggers next attempt to queue it, |
| it works with freed memory. |
| |
| Fix this by using cancel_delayed_work_sync() instead which makes sure |
| that work is done when it returns. |
| |
| The Linux kernel CVE team has assigned CVE-2024-26724 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.7 with commit 496fd0a26bbf73b6b12407ee4fbe5ff49d659a6d and fixed in 6.7.6 with commit 1596126ea50228f0ed96697bae4e9368fda02c56 |
| Issue introduced in 6.7 with commit 496fd0a26bbf73b6b12407ee4fbe5ff49d659a6d and fixed in 6.8 with commit aa1eec2f546f2afa8c98ec41e5d8ee488165d685 |
| |
| 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-2024-26724 |
| 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: |
| drivers/net/ethernet/mellanox/mlx5/core/dpll.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/1596126ea50228f0ed96697bae4e9368fda02c56 |
| https://git.kernel.org/stable/c/aa1eec2f546f2afa8c98ec41e5d8ee488165d685 |
