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KASAN: use-after-free Read in hdm_disconnect

Status: upstream: reported C repro on 2024/08/26 05:18
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+8142092e4d01872f00ae@syzkaller.appspotmail.com
First crash: 424d, last: 4d17h
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2025/01/02 upstream (ToT) 56e6a3499e14 C [report] KASAN: slab-use-after-free Read in hdm_disconnect
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: use-after-free Read in hdm_disconnect origin:upstream 19 C 134 23h25m 424d 0/3 upstream: reported C repro on 2024/08/26 06:04
upstream KASAN: slab-use-after-free Read in hdm_disconnect usb 19 C error 18676 37m 452d 2/29 upstream: reported C repro on 2024/07/29 11:32
linux-6.6 KASAN: slab-use-after-free Read in hdm_disconnect origin:upstream 19 C 47 20h32m 115d 0/2 upstream: reported C repro on 2025/07/02 01:51
▶ ▼ Last patch testing requests (9)
Created Duration User Patch Repo Result
2025/09/23 11:30 14m retest repro linux-5.15.y report log
2025/09/23 11:30 16m retest repro linux-5.15.y report log
2025/09/23 11:30 11m retest repro linux-5.15.y report log
2025/09/23 11:30 11m retest repro linux-5.15.y report log
2025/09/23 11:30 14m retest repro linux-5.15.y report log
2025/06/18 20:54 18m retest repro linux-5.15.y error
2025/05/18 06:44 18m retest repro linux-5.15.y report log
2025/05/18 06:44 15m retest repro linux-5.15.y report log
2025/05/18 06:44 19m retest repro linux-5.15.y report log

Sample crash report:
usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1: Product: syz
usb 1-1: Manufacturer: syz
usb 1-1: SerialNumber: syz
usb 1-1: config 0 descriptor??
usb 1-1: USB disconnect, device number 2
==================================================================
BUG: KASAN: use-after-free in hdm_disconnect+0x109/0x1c0 drivers/most/most_usb.c:1125
Read of size 8 at addr ffff8880256d9960 by task kworker/1:3/4164

CPU: 1 PID: 4164 Comm: kworker/1:3 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 hdm_disconnect+0x109/0x1c0 drivers/most/most_usb.c:1125
 usb_unbind_interface+0x1cd/0x840 drivers/usb/core/driver.c:458
 __device_release_driver drivers/base/dd.c:1229 [inline]
 device_release_driver_internal+0x50e/0x7f0 drivers/base/dd.c:1262
 bus_remove_device+0x2e5/0x400 drivers/base/bus.c:531
 device_del+0x6e2/0xbd0 drivers/base/core.c:3600
 usb_disable_device+0x3b8/0x840 drivers/usb/core/message.c:1414
 usb_disconnect+0x33c/0x8c0 drivers/usb/core/hub.c:2248
 hub_port_connect drivers/usb/core/hub.c:5299 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5595 [inline]
 port_event drivers/usb/core/hub.c:5741 [inline]
 hub_event+0x1d58/0x54c0 drivers/usb/core/hub.c:5823
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 4164:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 kmem_cache_alloc_trace+0x143/0x290 mm/slub.c:3247
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 hdm_probe+0x91/0x13d0 drivers/most/most_usb.c:959
 usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396
 really_probe+0x24e/0xb60 drivers/base/dd.c:595
 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:755
 driver_probe_device+0x50/0x420 drivers/base/dd.c:785
 __device_attach_driver+0x2b9/0x500 drivers/base/dd.c:907
 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:429
 __device_attach+0x359/0x570 drivers/base/dd.c:979
 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:489
 device_add+0xb48/0xfd0 drivers/base/core.c:3412
 usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238
 usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293
 really_probe+0x24e/0xb60 drivers/base/dd.c:595
 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:755
 driver_probe_device+0x50/0x420 drivers/base/dd.c:785
 __device_attach_driver+0x2b9/0x500 drivers/base/dd.c:907
 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:429
 __device_attach+0x359/0x570 drivers/base/dd.c:979
 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:489
 device_add+0xb48/0xfd0 drivers/base/core.c:3412
 usb_new_device+0xc17/0x18e0 drivers/usb/core/hub.c:2593
 hub_port_connect drivers/usb/core/hub.c:5455 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5595 [inline]
 port_event drivers/usb/core/hub.c:5741 [inline]
 hub_event+0x2cdf/0x54c0 drivers/usb/core/hub.c:5823
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Freed by task 4164:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 device_release+0x91/0x1c0
 kobject_cleanup lib/kobject.c:713 [inline]
 kobject_release lib/kobject.c:744 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x224/0x460 lib/kobject.c:761
 hdm_disconnect+0xef/0x1c0 drivers/most/most_usb.c:1123
 usb_unbind_interface+0x1cd/0x840 drivers/usb/core/driver.c:458
 __device_release_driver drivers/base/dd.c:1229 [inline]
 device_release_driver_internal+0x50e/0x7f0 drivers/base/dd.c:1262
 bus_remove_device+0x2e5/0x400 drivers/base/bus.c:531
 device_del+0x6e2/0xbd0 drivers/base/core.c:3600
 usb_disable_device+0x3b8/0x840 drivers/usb/core/message.c:1414
 usb_disconnect+0x33c/0x8c0 drivers/usb/core/hub.c:2248
 hub_port_connect drivers/usb/core/hub.c:5299 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5595 [inline]
 port_event drivers/usb/core/hub.c:5741 [inline]
 hub_event+0x1d58/0x54c0 drivers/usb/core/hub.c:5823
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

The buggy address belongs to the object at ffff8880256d8000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 6496 bytes inside of
 8192-byte region [ffff8880256d8000, ffff8880256da000)
The buggy address belongs to the page:
page:ffffea000095b600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x256d8
head:ffffea000095b600 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 0000000100000001 ffff888017442280
raw: 0000000000000000 0000000080020002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, ts 11788827686, free_ts 0
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5465
 alloc_page_interleave+0x22/0x1c0 mm/mempolicy.c:2031
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 __kmalloc+0x1c9/0x300 mm/slub.c:4403
 kmalloc include/linux/slab.h:596 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 __usb_create_hcd+0x5f/0x840 drivers/usb/core/hcd.c:2583
 vhci_hcd_probe+0x1d8/0x3b0 drivers/usb/usbip/vhci_hcd.c:1371
 platform_probe+0x131/0x1b0 drivers/base/platform.c:1391
 really_probe+0x24e/0xb60 drivers/base/dd.c:595
 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:755
 driver_probe_device+0x50/0x420 drivers/base/dd.c:785
 __device_attach_driver+0x2b9/0x500 drivers/base/dd.c:907
 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:429
 __device_attach+0x359/0x570 drivers/base/dd.c:979
 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:489
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8880256d9800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880256d9880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880256d9900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff8880256d9980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880256d9a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (122):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/28 14:11 linux-5.15.y 91786f140358 d3ccff63 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/04/09 17:57 linux-5.15.y 0c935c049b5c 47d015b1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2024/08/26 06:55 linux-5.15.y fa93fa65db6e d7d32352 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2024/08/26 06:23 linux-5.15.y fa93fa65db6e d7d32352 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2024/08/26 05:52 linux-5.15.y fa93fa65db6e d7d32352 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/10/20 10:34 linux-5.15.y ac56c046adf4 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/18 18:50 linux-5.15.y 29e53a5b1c4f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/16 14:38 linux-5.15.y 29e53a5b1c4f 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/16 09:05 linux-5.15.y 29e53a5b1c4f 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/16 00:25 linux-5.15.y 29e53a5b1c4f 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/13 04:24 linux-5.15.y 29e53a5b1c4f ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/08 15:41 linux-5.15.y 29e53a5b1c4f 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/05 22:41 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/03 14:30 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/10/02 06:29 linux-5.15.y 43bb85222e53 267f56c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/09/30 06:18 linux-5.15.y 43bb85222e53 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/09/03 02:08 linux-5.15.y 01879f56bdde 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/09/01 04:43 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/08/22 23:01 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/08/16 05:27 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/08/08 21:58 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/07/27 19:54 linux-5.15.y c79648372d02 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/07/27 12:32 linux-5.15.y c79648372d02 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/07/26 22:14 linux-5.15.y c79648372d02 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/07/24 19:19 linux-5.15.y c79648372d02 65d60d73 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/07/02 17:55 linux-5.15.y 3dea0e7f549e bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/07/02 01:57 linux-5.15.y 3dea0e7f549e 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/06/26 05:29 linux-5.15.y 1c700860e8bc 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/06/23 00:23 linux-5.15.y 1c700860e8bc d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/06/03 21:01 linux-5.15.y 98f47d0e9b8c a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/05/25 08:05 linux-5.15.y 98f47d0e9b8c ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/05/03 10:48 linux-5.15.y 16fdf2c7111b b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/04/27 11:27 linux-5.15.y f7347f400572 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/04/26 13:41 linux-5.15.y f7347f400572 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/04/23 14:18 linux-5.15.y f7347f400572 53a8b9bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/04/22 08:55 linux-5.15.y f7347f400572 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/04/18 23:36 linux-5.15.y f7347f400572 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hdm_disconnect
2025/08/09 21:08 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/17 21:58 linux-5.15.y f7347f400572 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/17 09:41 linux-5.15.y f7347f400572 229db4cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/17 04:41 linux-5.15.y f7347f400572 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/15 22:53 linux-5.15.y f7347f400572 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/15 10:40 linux-5.15.y f7347f400572 23b969b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/13 01:30 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/10 16:35 linux-5.15.y f7347f400572 1ef3ab4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/10 13:30 linux-5.15.y f7347f400572 988b336c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/09 22:43 linux-5.15.y 0c935c049b5c 988b336c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2025/04/09 20:35 linux-5.15.y 0c935c049b5c 47d015b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
2024/08/26 05:17 linux-5.15.y fa93fa65db6e d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in hdm_disconnect
* Struck through repros no longer work on HEAD.