ghsa-wchf-3rq4-vh73
Vulnerability from github
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: __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
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] ---truncated---
{
"affected": [],
"aliases": [
"CVE-2024-47706"
],
"database_specific": {
"cwe_ids": [
"CWE-416"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-10-21T12:15:07Z",
"severity": "MODERATE"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nblock, bfq: fix possible UAF for bfqq-\u003ebic with merge chain\n\n1) initial state, three tasks:\n\n\t\tProcess 1 Process 2\tProcess 3\n\t\t (BIC1) (BIC2)\t\t (BIC3)\n\t\t | \u039b | \u039b\t\t | \u039b\n\t\t | | | |\t\t | |\n\t\t V | V |\t\t V |\n\t\t bfqq1 bfqq2\t\t bfqq3\nprocess ref:\t 1\t\t 1\t\t 1\n\n2) bfqq1 merged to bfqq2:\n\n\t\tProcess 1 Process 2\tProcess 3\n\t\t (BIC1) (BIC2)\t\t (BIC3)\n\t\t | |\t\t | \u039b\n\t\t \\--------------\\|\t\t | |\n\t\t V\t\t V |\n\t\t bfqq1---------\u003ebfqq2\t\t bfqq3\nprocess ref:\t 0\t\t 2\t\t 1\n\n3) bfqq2 merged to bfqq3:\n\n\t\tProcess 1 Process 2\tProcess 3\n\t\t (BIC1) (BIC2)\t\t (BIC3)\n\t here -\u003e \u039b |\t\t |\n\t\t \\--------------\\ \\-------------\\|\n\t\t V\t\t V\n\t\t bfqq1---------\u003ebfqq2----------\u003ebfqq3\nprocess ref:\t 0\t\t 1\t\t 3\n\nIn this case, IO from Process 1 will get bfqq2 from BIC1 first, and then\nget bfqq3 through merge chain, and finially handle IO by bfqq3.\nHowerver, current code will think bfqq2 is owned by BIC1, like initial\nstate, and set bfqq2-\u003ebic to BIC1.\n\nbfq_insert_request\n-\u003e by Process 1\n bfqq = bfq_init_rq(rq)\n bfqq = bfq_get_bfqq_handle_split\n bfqq = bic_to_bfqq\n -\u003e get bfqq2 from BIC1\n bfqq-\u003eref++\n rq-\u003eelv.priv[0] = bic\n rq-\u003eelv.priv[1] = bfqq\n if (bfqq_process_refs(bfqq) == 1)\n bfqq-\u003ebic = bic\n -\u003e record BIC1 to bfqq2\n\n __bfq_insert_request\n new_bfqq = bfq_setup_cooperator\n -\u003e get bfqq3 from bfqq2-\u003enew_bfqq\n bfqq_request_freed(bfqq)\n new_bfqq-\u003eref++\n rq-\u003eelv.priv[1] = new_bfqq\n -\u003e handle IO by bfqq3\n\nFix the problem by checking bfqq is from merge chain fist. And this\nmight fix a following problem reported by our syzkaller(unreproducible):\n\n==================================================================\nBUG: KASAN: slab-use-after-free in bfq_do_early_stable_merge block/bfq-iosched.c:5692 [inline]\nBUG: KASAN: slab-use-after-free in bfq_do_or_sched_stable_merge block/bfq-iosched.c:5805 [inline]\nBUG: KASAN: slab-use-after-free in bfq_get_queue+0x25b0/0x2610 block/bfq-iosched.c:5889\nWrite of size 1 at addr ffff888123839eb8 by task kworker/0:1H/18595\n\nCPU: 0 PID: 18595 Comm: kworker/0:1H Tainted: G L 6.6.0-07439-gba2303cacfda #6\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014\nWorkqueue: kblockd blk_mq_requeue_work\nCall Trace:\n \u003cTASK\u003e\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0x91/0xf0 lib/dump_stack.c:106\n print_address_description mm/kasan/report.c:364 [inline]\n print_report+0x10d/0x610 mm/kasan/report.c:475\n kasan_report+0x8e/0xc0 mm/kasan/report.c:588\n bfq_do_early_stable_merge block/bfq-iosched.c:5692 [inline]\n bfq_do_or_sched_stable_merge block/bfq-iosched.c:5805 [inline]\n bfq_get_queue+0x25b0/0x2610 block/bfq-iosched.c:5889\n bfq_get_bfqq_handle_split+0x169/0x5d0 block/bfq-iosched.c:6757\n bfq_init_rq block/bfq-iosched.c:6876 [inline]\n bfq_insert_request block/bfq-iosched.c:6254 [inline]\n bfq_insert_requests+0x1112/0x5cf0 block/bfq-iosched.c:6304\n blk_mq_insert_request+0x290/0x8d0 block/blk-mq.c:2593\n blk_mq_requeue_work+0x6bc/0xa70 block/blk-mq.c:1502\n process_one_work kernel/workqueue.c:2627 [inline]\n process_scheduled_works+0x432/0x13f0 kernel/workqueue.c:2700\n worker_thread+0x6f2/0x1160 kernel/workqueue.c:2781\n kthread+0x33c/0x440 kernel/kthread.c:388\n ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147\n ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:305\n \u003c/TASK\u003e\n\nAllocated by task 20776:\n kasan_save_stack+0x20/0x40 mm/kasan/common.c:45\n kasan_set_track+0x25/0x30 mm/kasan/common.c:52\n __kasan_slab_alloc+0x87/0x90 mm/kasan/common.c:328\n kasan_slab_alloc include/linux/kasan.h:188 [inline]\n slab_post_alloc_hook mm/slab.h:763 [inline]\n slab_alloc_node mm/slub.c:3458 [inline]\n kmem_cache_alloc_node+0x1a4/0x6f0 mm/slub.c:3503\n ioc_create_icq block/blk-ioc.c:370 [inline]\n---truncated---",
"id": "GHSA-wchf-3rq4-vh73",
"modified": "2024-11-08T18:30:44Z",
"published": "2024-10-21T12:30:55Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-47706"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/18ad4df091dd5d067d2faa8fce1180b79f7041a7"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6d130db286ad0ea392c96ebb2551acf0d7308048"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7faed2896d78e48ec96229e73b30b0af6c00a9aa"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/880692ee233ba63808182705b3333403413b58f5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8aa9de02a4be2e7006e636816ce19b0d667ceaa3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a9bdd5b36887d2bacb8bc777fd18317c99fc2587"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/bc2140534b2aae752e4f7cb4489642dbb5ec4777"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ddbdaad123254fb53e32480cb74a486a6868b1e0"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e1277ae780cca4e69ef5468d4582dfd48f0b8320"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
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