syzbot


KASAN: slab-use-after-free Write in as102_release (2)

Status: upstream: reported on 2025/05/02 23:13
Subsystems: media
[Documentation on labels]
Reported-by: syzbot+47321e8fd5a4c84088db@syzkaller.appspotmail.com
First crash: 97d, last: 5d07h
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] media: usb: as102: reset file private data on device release 1 (1) 2025/05/07 11:18
[syzbot] [media?] KASAN: slab-use-after-free Write in as102_release (2) 0 (1) 2025/05/02 23:13
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Write in as102_release media 9 204d 207d 0/28 auto-obsoleted due to no activity on 2025/02/01 23:16

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: slab-use-after-free in atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:400 [inline]
BUG: KASAN: slab-use-after-free in __refcount_sub_and_test include/linux/refcount.h:389 [inline]
BUG: KASAN: slab-use-after-free in __refcount_dec_and_test include/linux/refcount.h:432 [inline]
BUG: KASAN: slab-use-after-free in refcount_dec_and_test include/linux/refcount.h:450 [inline]
BUG: KASAN: slab-use-after-free in kref_put include/linux/kref.h:64 [inline]
BUG: KASAN: slab-use-after-free in as102_release+0x56/0x110 drivers/media/usb/as102/as102_usb_drv.c:456
Write of size 4 at addr ffff88812356c150 by task syz.3.6675/1811

CPU: 1 UID: 0 PID: 1811 Comm: syz.3.6675 Not tainted 6.15.0-rc4-syzkaller-00104-g588d032e9e56 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
 atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:400 [inline]
 __refcount_sub_and_test include/linux/refcount.h:389 [inline]
 __refcount_dec_and_test include/linux/refcount.h:432 [inline]
 refcount_dec_and_test include/linux/refcount.h:450 [inline]
 kref_put include/linux/kref.h:64 [inline]
 as102_release+0x56/0x110 drivers/media/usb/as102/as102_usb_drv.c:456
 __fput+0x3ff/0xb70 fs/file_table.c:465
 task_work_run+0x14d/0x240 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x24e/0x260 kernel/entry/common.c:218
 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f9fe4e969
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffc1e81c28 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000033ebbd RCX: 00007f0f9fe4e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f0fa0077ba0 R08: 0000000000000001 R09: 0000001ec1e81f1f
R10: 00007f0f9fcc0000 R11: 0000000000000246 R12: 00007f0fa0075fac
R13: 00007f0fa0075fa0 R14: ffffffffffffffff R15: 00007fffc1e81d40
 </TASK>

Allocated by task 31353:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:394
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 as102_usb_probe+0x54/0xb00 drivers/media/usb/as102/as102_usb_drv.c:348
 usb_probe_interface+0x300/0x9c0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:579 [inline]
 really_probe+0x23e/0xa90 drivers/base/dd.c:657
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1a70 drivers/base/core.c:3692
 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:579 [inline]
 really_probe+0x23e/0xa90 drivers/base/dd.c:657
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1a70 drivers/base/core.c:3692
 usb_new_device+0xd07/0x1a20 drivers/usb/core/hub.c:2663
 hub_port_connect drivers/usb/core/hub.c:5535 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5675 [inline]
 port_event drivers/usb/core/hub.c:5835 [inline]
 hub_event+0x2f85/0x5030 drivers/usb/core/hub.c:5917
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 31353:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x37/0x50 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2398 [inline]
 slab_free mm/slub.c:4656 [inline]
 kfree+0x286/0x470 mm/slub.c:4855
 as102_usb_probe+0x697/0xb00 drivers/media/usb/as102/as102_usb_drv.c:410
 usb_probe_interface+0x300/0x9c0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:579 [inline]
 really_probe+0x23e/0xa90 drivers/base/dd.c:657
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1a70 drivers/base/core.c:3692
 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:579 [inline]
 really_probe+0x23e/0xa90 drivers/base/dd.c:657
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1a70 drivers/base/core.c:3692
 usb_new_device+0xd07/0x1a20 drivers/usb/core/hub.c:2663
 hub_port_connect drivers/usb/core/hub.c:5535 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5675 [inline]
 port_event drivers/usb/core/hub.c:5835 [inline]
 hub_event+0x2f85/0x5030 drivers/usb/core/hub.c:5917
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88812356c000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 336 bytes inside of
 freed 4096-byte region [ffff88812356c000, ffff88812356d000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x123568
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff888100042140 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 0200000000000040 ffff888100042140 0000000000000000 dead000000000001
head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 0200000000000003 ffffea00048d5a01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008
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 2839, tgid 2839 (udevd), ts 95840852080, free_ts 95516620849
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0xfec/0x2d90 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x25c/0x2160 mm/page_alloc.c:4970
 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2468 [inline]
 allocate_slab mm/slub.c:2632 [inline]
 new_slab+0x244/0x340 mm/slub.c:2686
 ___slab_alloc+0xda5/0x1940 mm/slub.c:3872
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3962
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 __kmalloc_cache_noprof+0x209/0x3c0 mm/slub.c:4367
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 uevent_show+0x165/0x3a0 drivers/base/core.c:2754
 dev_attr_show+0x53/0xe0 drivers/base/core.c:2424
 sysfs_kf_seq_show+0x213/0x3e0 fs/sysfs/file.c:65
 seq_read_iter+0x506/0x12c0 fs/seq_file.c:230
 kernfs_fop_read_iter+0x40f/0x5a0 fs/kernfs/file.c:279
 new_sync_read fs/read_write.c:489 [inline]
 vfs_read+0x8c8/0xc70 fs/read_write.c:570
 ksys_read+0x12a/0x240 fs/read_write.c:713
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
page last free pid 5199 tgid 5199 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0x66c/0xe70 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2730 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3199
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4161 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 kmem_cache_alloc_node_noprof+0x14d/0x3a0 mm/slub.c:4262
 __alloc_skb+0x2b2/0x380 net/core/skbuff.c:658
 alloc_skb include/linux/skbuff.h:1340 [inline]
 netlink_alloc_large_skb+0x69/0x130 net/netlink/af_netlink.c:1187
 netlink_sendmsg+0x6a1/0xdd0 net/netlink/af_netlink.c:1858
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg net/socket.c:727 [inline]
 ____sys_sendmsg+0xa95/0xc70 net/socket.c:2566
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2620
 __sys_sendmsg+0x16d/0x220 net/socket.c:2652
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88812356c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812356c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88812356c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88812356c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812356c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/11 22:52 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 588d032e9e56 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Write in as102_release
2025/05/04 06:47 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 588d032e9e56 b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Write in as102_release
2025/05/03 23:28 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 588d032e9e56 b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Write in as102_release
2025/05/02 23:12 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 588d032e9e56 b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Write in as102_release
2025/05/02 02:53 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 588d032e9e56 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Write in as102_release
2025/03/17 14:06 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 3a85c1011540 948c34e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Write in as102_release
2025/02/13 04:54 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 9682c35ff6ec b27c2402 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Write in as102_release
2025/02/09 03:27 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 9682c35ff6ec ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Write in as102_release
* Struck through repros no longer work on HEAD.