| 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-2024-47706: block, bfq: fix possible UAF for bfqq->bic with merge chain |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| block, bfq: fix possible UAF for bfqq->bic with merge chain |
| |
| 1) initial state, three tasks: |
| |
| Process 1 Process 2 Process 3 |
| (BIC1) (BIC2) (BIC3) |
| | Λ | Λ | Λ |
| | | | | | | |
| V | V | V | |
| bfqq1 bfqq2 bfqq3 |
| process ref: 1 1 1 |
| |
| 2) bfqq1 merged to bfqq2: |
| |
| Process 1 Process 2 Process 3 |
| (BIC1) (BIC2) (BIC3) |
| | | | Λ |
| \--------------\| | | |
| V V | |
| bfqq1--------->bfqq2 bfqq3 |
| process ref: 0 2 1 |
| |
| 3) bfqq2 merged to bfqq3: |
| |
| Process 1 Process 2 Process 3 |
| (BIC1) (BIC2) (BIC3) |
| here -> Λ | | |
| \--------------\ \-------------\| |
| V V |
| bfqq1--------->bfqq2---------->bfqq3 |
| process ref: 0 1 3 |
| |
| In this case, IO from Process 1 will get bfqq2 from BIC1 first, and then |
| get bfqq3 through merge chain, and finially handle IO by bfqq3. |
| Howerver, current code will think bfqq2 is owned by BIC1, like initial |
| state, and set bfqq2->bic to BIC1. |
| |
| bfq_insert_request |
| -> by Process 1 |
| bfqq = bfq_init_rq(rq) |
| bfqq = bfq_get_bfqq_handle_split |
| bfqq = bic_to_bfqq |
| -> get bfqq2 from BIC1 |
| bfqq->ref++ |
| rq->elv.priv[0] = bic |
| rq->elv.priv[1] = bfqq |
| if (bfqq_process_refs(bfqq) == 1) |
| bfqq->bic = bic |
| -> record BIC1 to bfqq2 |
| |
| __bfq_insert_request |
| new_bfqq = bfq_setup_cooperator |
| -> get bfqq3 from bfqq2->new_bfqq |
| bfqq_request_freed(bfqq) |
| new_bfqq->ref++ |
| rq->elv.priv[1] = new_bfqq |
| -> handle IO by bfqq3 |
| |
| Fix the problem by checking bfqq is from merge chain fist. And this |
| might fix a following problem reported by our syzkaller(unreproducible): |
| |
| ================================================================== |
| BUG: KASAN: slab-use-after-free in bfq_do_early_stable_merge block/bfq-iosched.c:5692 [inline] |
| BUG: KASAN: slab-use-after-free in bfq_do_or_sched_stable_merge block/bfq-iosched.c:5805 [inline] |
| BUG: KASAN: slab-use-after-free in bfq_get_queue+0x25b0/0x2610 block/bfq-iosched.c:5889 |
| Write of size 1 at addr ffff888123839eb8 by task kworker/0:1H/18595 |
| |
| CPU: 0 PID: 18595 Comm: kworker/0:1H Tainted: G L 6.6.0-07439-gba2303cacfda #6 |
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 |
| Workqueue: kblockd blk_mq_requeue_work |
| Call Trace: |
| <TASK> |
| __dump_stack lib/dump_stack.c:88 [inline] |
| dump_stack_lvl+0x91/0xf0 lib/dump_stack.c:106 |
| print_address_description mm/kasan/report.c:364 [inline] |
| print_report+0x10d/0x610 mm/kasan/report.c:475 |
| kasan_report+0x8e/0xc0 mm/kasan/report.c:588 |
| bfq_do_early_stable_merge block/bfq-iosched.c:5692 [inline] |
| bfq_do_or_sched_stable_merge block/bfq-iosched.c:5805 [inline] |
| bfq_get_queue+0x25b0/0x2610 block/bfq-iosched.c:5889 |
| bfq_get_bfqq_handle_split+0x169/0x5d0 block/bfq-iosched.c:6757 |
| bfq_init_rq block/bfq-iosched.c:6876 [inline] |
| bfq_insert_request block/bfq-iosched.c:6254 [inline] |
| bfq_insert_requests+0x1112/0x5cf0 block/bfq-iosched.c:6304 |
| blk_mq_insert_request+0x290/0x8d0 block/blk-mq.c:2593 |
| blk_mq_requeue_work+0x6bc/0xa70 block/blk-mq.c:1502 |
| process_one_work kernel/workqueue.c:2627 [inline] |
| process_scheduled_works+0x432/0x13f0 kernel/workqueue.c:2700 |
| worker_thread+0x6f2/0x1160 kernel/workqueue.c:2781 |
| kthread+0x33c/0x440 kernel/kthread.c:388 |
| ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 |
| ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:305 |
| </TASK> |
| |
| Allocated by task 20776: |
| kasan_save_stack+0x20/0x40 mm/kasan/common.c:45 |
| kasan_set_track+0x25/0x30 mm/kasan/common.c:52 |
| __kasan_slab_alloc+0x87/0x90 mm/kasan/common.c:328 |
| kasan_slab_alloc include/linux/kasan.h:188 [inline] |
| slab_post_alloc_hook mm/slab.h:763 [inline] |
| slab_alloc_node mm/slub.c:3458 [inline] |
| kmem_cache_alloc_node+0x1a4/0x6f0 mm/slub.c:3503 |
| ioc_create_icq block/blk-ioc.c:370 [inline] |
| ioc_find_get_icq+0x180/0xaa0 block/blk-ioc.c:436 |
| bfq_prepare_request+0x39/0xf0 block/bfq-iosched.c:6812 |
| blk_mq_rq_ctx_init.isra.7+0x6ac/0xa00 block/blk-mq.c:403 |
| __blk_mq_alloc_requests+0xcc0/0x1070 block/blk-mq.c:517 |
| blk_mq_get_new_requests block/blk-mq.c:2940 [inline] |
| blk_mq_submit_bio+0x624/0x27c0 block/blk-mq.c:3042 |
| __submit_bio+0x331/0x6f0 block/blk-core.c:624 |
| __submit_bio_noacct_mq block/blk-core.c:703 [inline] |
| submit_bio_noacct_nocheck+0x816/0xb40 block/blk-core.c:732 |
| submit_bio_noacct+0x7a6/0x1b50 block/blk-core.c:826 |
| xlog_write_iclog+0x7d5/0xa00 fs/xfs/xfs_log.c:1958 |
| xlog_state_release_iclog+0x3b8/0x720 fs/xfs/xfs_log.c:619 |
| xlog_cil_push_work+0x19c5/0x2270 fs/xfs/xfs_log_cil.c:1330 |
| process_one_work kernel/workqueue.c:2627 [inline] |
| process_scheduled_works+0x432/0x13f0 kernel/workqueue.c:2700 |
| worker_thread+0x6f2/0x1160 kernel/workqueue.c:2781 |
| kthread+0x33c/0x440 kernel/kthread.c:388 |
| ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 |
| ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:305 |
| |
| Freed by task 946: |
| kasan_save_stack+0x20/0x40 mm/kasan/common.c:45 |
| kasan_set_track+0x25/0x30 mm/kasan/common.c:52 |
| kasan_save_free_info+0x2b/0x50 mm/kasan/generic.c:522 |
| ____kasan_slab_free mm/kasan/common.c:236 [inline] |
| __kasan_slab_free+0x12c/0x1c0 mm/kasan/common.c:244 |
| kasan_slab_free include/linux/kasan.h:164 [inline] |
| slab_free_hook mm/slub.c:1815 [inline] |
| slab_free_freelist_hook mm/slub.c:1841 [inline] |
| slab_free mm/slub.c:3786 [inline] |
| kmem_cache_free+0x118/0x6f0 mm/slub.c:3808 |
| rcu_do_batch+0x35c/0xe30 kernel/rcu/tree.c:2189 |
| rcu_core+0x819/0xd90 kernel/rcu/tree.c:2462 |
| __do_softirq+0x1b0/0x7a2 kernel/softirq.c:553 |
| |
| Last potentially related work creation: |
| kasan_save_stack+0x20/0x40 mm/kasan/common.c:45 |
| __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 |
| __call_rcu_common kernel/rcu/tree.c:2712 [inline] |
| call_rcu+0xce/0x1020 kernel/rcu/tree.c:2826 |
| ioc_destroy_icq+0x54c/0x830 block/blk-ioc.c:105 |
| ioc_release_fn+0xf0/0x360 block/blk-ioc.c:124 |
| process_one_work kernel/workqueue.c:2627 [inline] |
| process_scheduled_works+0x432/0x13f0 kernel/workqueue.c:2700 |
| worker_thread+0x6f2/0x1160 kernel/workqueue.c:2781 |
| kthread+0x33c/0x440 kernel/kthread.c:388 |
| ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 |
| ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:305 |
| |
| Second to last potentially related work creation: |
| kasan_save_stack+0x20/0x40 mm/kasan/common.c:45 |
| __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 |
| __call_rcu_common kernel/rcu/tree.c:2712 [inline] |
| call_rcu+0xce/0x1020 kernel/rcu/tree.c:2826 |
| ioc_destroy_icq+0x54c/0x830 block/blk-ioc.c:105 |
| ioc_release_fn+0xf0/0x360 block/blk-ioc.c:124 |
| process_one_work kernel/workqueue.c:2627 [inline] |
| process_scheduled_works+0x432/0x13f0 kernel/workqueue.c:2700 |
| worker_thread+0x6f2/0x1160 kernel/workqueue.c:2781 |
| kthread+0x33c/0x440 kernel/kthread.c:388 |
| ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 |
| ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:305 |
| |
| The buggy address belongs to the object at ffff888123839d68 |
| which belongs to the cache bfq_io_cq of size 1360 |
| The buggy address is located 336 bytes inside of |
| freed 1360-byte region [ffff888123839d68, ffff88812383a2b8) |
| |
| The buggy address belongs to the physical page: |
| page:ffffea00048e0e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88812383f588 pfn:0x123838 |
| head:ffffea00048e0e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 |
| flags: 0x17ffffc0000a40(workingset|slab|head|node=0|zone=2|lastcpupid=0x1fffff) |
| page_type: 0xffffffff() |
| raw: 0017ffffc0000a40 ffff88810588c200 ffffea00048ffa10 ffff888105889488 |
| raw: ffff88812383f588 0000000000150006 00000001ffffffff 0000000000000000 |
| page dumped because: kasan: bad access detected |
| |
| Memory state around the buggy address: |
| ffff888123839d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| ffff888123839e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| >ffff888123839e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| ^ |
| ffff888123839f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| ffff888123839f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb |
| ================================================================== |
| |
| The Linux kernel CVE team has assigned CVE-2024-47706 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 4.19.323 with commit a9bdd5b36887d2bacb8bc777fd18317c99fc2587 |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 5.4.285 with commit bc2140534b2aae752e4f7cb4489642dbb5ec4777 |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 5.10.227 with commit e1277ae780cca4e69ef5468d4582dfd48f0b8320 |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 5.15.168 with commit 8aa9de02a4be2e7006e636816ce19b0d667ceaa3 |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 6.1.113 with commit ddbdaad123254fb53e32480cb74a486a6868b1e0 |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 6.6.54 with commit 7faed2896d78e48ec96229e73b30b0af6c00a9aa |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 6.10.13 with commit 880692ee233ba63808182705b3333403413b58f5 |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 6.11.2 with commit 6d130db286ad0ea392c96ebb2551acf0d7308048 |
| Issue introduced in 4.12 with commit 36eca894832351feed9072d0f97eb06fc9482ca4 and fixed in 6.12 with commit 18ad4df091dd5d067d2faa8fce1180b79f7041a7 |
| |
| 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-2024-47706 |
| 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: |
| block/bfq-iosched.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/a9bdd5b36887d2bacb8bc777fd18317c99fc2587 |
| https://git.kernel.org/stable/c/bc2140534b2aae752e4f7cb4489642dbb5ec4777 |
| https://git.kernel.org/stable/c/e1277ae780cca4e69ef5468d4582dfd48f0b8320 |
| https://git.kernel.org/stable/c/8aa9de02a4be2e7006e636816ce19b0d667ceaa3 |
| https://git.kernel.org/stable/c/ddbdaad123254fb53e32480cb74a486a6868b1e0 |
| https://git.kernel.org/stable/c/7faed2896d78e48ec96229e73b30b0af6c00a9aa |
| https://git.kernel.org/stable/c/880692ee233ba63808182705b3333403413b58f5 |
| https://git.kernel.org/stable/c/6d130db286ad0ea392c96ebb2551acf0d7308048 |
| https://git.kernel.org/stable/c/18ad4df091dd5d067d2faa8fce1180b79f7041a7 |
