Hello, syzbot found the following issue on: HEAD commit: 24be4d0b46bb arch/arm64/mm/fault: Fix undeclared variable .. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing console output: https://syzkaller.appspot.com/x/log.txt?x=11383b04a80000 kernel config: https://syzkaller.appspot.com/x/.config?x=f9122dc1c4589f4c dashboard link: https://syzkaller.appspot.com/bug?extid=621409285c4156a009b3 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14e2e43ca80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=109a3a90a80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/b64cbb1118f1/disk-24be4d0b.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/568048c1dd0d/vmlinux-24be4d0b.xz kernel image: https://storage.googleapis.com/syzbot-assets/84ac264152e7/bzImage-24be4d0b.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+621409285c4156a009b3@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in pvr2_context_set_notify+0x2c4/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:35 Read of size 4 at addr ffff88810eb986d8 by task kworker/0:0/7 CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.4.0-syzkaller-11311-g24be4d0b46bb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:364 print_report mm/kasan/report.c:475 [inline] kasan_report+0x11d/0x130 mm/kasan/report.c:588 pvr2_context_set_notify+0x2c4/0x310 drivers/media/usb/pvrusb2/pvrusb2-context.c:35 pvr_disconnect+0x80/0xf0 drivers/media/usb/pvrusb2/pvrusb2-main.c:79 usb_unbind_interface+0x1dc/0x8e0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] device_remove+0x11f/0x170 drivers/base/dd.c:561 __device_release_driver drivers/base/dd.c:1270 [inline] device_release_driver_internal+0x443/0x610 drivers/base/dd.c:1293 bus_remove_device+0x22c/0x420 drivers/base/bus.c:574 device_del+0x399/0xa30 drivers/base/core.c:3814 usb_disable_device+0x360/0x7b0 drivers/usb/core/message.c:1420 usb_disconnect+0x2db/0x8a0 drivers/usb/core/hub.c:2253 hub_port_connect drivers/usb/core/hub.c:5261 [inline] hub_port_connect_change drivers/usb/core/hub.c:5566 [inline] port_event drivers/usb/core/hub.c:5726 [inline] hub_event+0x2073/0x4ed0 drivers/usb/core/hub.c:5808 process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597 process_scheduled_works kernel/workqueue.c:2664 [inline] worker_thread+0x881/0x10c0 kernel/workqueue.c:2750 kthread+0x344/0x440 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Allocated by task 7: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x7b/0x90 mm/kasan/common.c:383 kmalloc include/linux/slab.h:579 [inline] kzalloc include/linux/slab.h:700 [inline] pvr2_context_create+0x53/0x2a0 drivers/media/usb/pvrusb2/pvrusb2-context.c:207 pvr_probe+0x25/0xe0 drivers/media/usb/pvrusb2/pvrusb2-main.c:54 usb_probe_interface+0x30f/0x960 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x240/0xca0 drivers/base/dd.c:658 __driver_probe_device+0x1df/0x4b0 drivers/base/dd.c:798 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:828 __device_attach_driver+0x1d4/0x2e0 drivers/base/dd.c:956 bus_for_each_drv+0x149/0x1d0 drivers/base/bus.c:457 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1028 bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532 device_add+0x112d/0x1a40 drivers/base/core.c:3625 usb_set_configuration+0x1196/0x1bc0 drivers/usb/core/message.c:2211 usb_generic_driver_probe+0xcf/0x130 drivers/usb/core/generic.c:238 usb_probe_device+0xd8/0x2c0 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x240/0xca0 drivers/base/dd.c:658 __driver_probe_device+0x1df/0x4b0 drivers/base/dd.c:798 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:828 __device_attach_driver+0x1d4/0x2e0 drivers/base/dd.c:956 bus_for_each_drv+0x149/0x1d0 drivers/base/bus.c:457 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1028 bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532 device_add+0x112d/0x1a40 drivers/base/core.c:3625 usb_new_device+0xcb2/0x19d0 drivers/usb/core/hub.c:2590 hub_port_connect drivers/usb/core/hub.c:5422 [inline] hub_port_connect_change drivers/usb/core/hub.c:5566 [inline] port_event drivers/usb/core/hub.c:5726 [inline] hub_event+0x2e3d/0x4ed0 drivers/usb/core/hub.c:5808 process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597 process_scheduled_works kernel/workqueue.c:2664 [inline] worker_thread+0x881/0x10c0 kernel/workqueue.c:2750 kthread+0x344/0x440 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Freed by task 892: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x144/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1792 [inline] slab_free_freelist_hook mm/slub.c:1818 [inline] slab_free mm/slub.c:3801 [inline] __kmem_cache_free+0xa1/0x350 mm/slub.c:3814 pvr2_context_check drivers/media/usb/pvrusb2/pvrusb2-context.c:137 [inline] pvr2_context_thread_func+0x664/0x8e0 drivers/media/usb/pvrusb2/pvrusb2-context.c:158 kthread+0x344/0x440 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 The buggy address belongs to the object at ffff88810eb98600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 216 bytes inside of freed 256-byte region [ffff88810eb98600, ffff88810eb98700) The buggy address belongs to the physical page: page:ffffea00043ae600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10eb98 head:ffffea00043ae600 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x200000000010200(slab|head|node=0|zone=2) page_type: 0xffffffff() raw: 0200000000010200 ffff888100041b40 ffffea00043ae300 0000000000000003 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 7338785555, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1570 prep_new_page mm/page_alloc.c:1577 [inline] get_page_from_freelist+0x13d5/0x2cb0 mm/page_alloc.c:3221 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4477 alloc_page_interleave+0x1e/0x1e0 mm/mempolicy.c:2112 alloc_pages+0x233/0x270 mm/mempolicy.c:2274 alloc_slab_page mm/slub.c:1862 [inline] allocate_slab+0x25f/0x390 mm/slub.c:2009 new_slab mm/slub.c:2062 [inline] ___slab_alloc+0xbc3/0x15d0 mm/slub.c:3215 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3314 __slab_alloc_node mm/slub.c:3367 [inline] slab_alloc_node mm/slub.c:3460 [inline] __kmem_cache_alloc_node+0x2c3/0x300 mm/slub.c:3509 __do_kmalloc_node mm/slab_common.c:984 [inline] __kmalloc_node_track_caller+0x4f/0x1a0 mm/slab_common.c:1005 __do_krealloc mm/slab_common.c:1373 [inline] krealloc+0x5e/0xf0 mm/slab_common.c:1406 add_sysfs_param+0xca/0x960 kernel/params.c:652 kernel_add_sysfs_param kernel/params.c:813 [inline] param_sysfs_builtin kernel/params.c:852 [inline] param_sysfs_builtin_init+0x241/0x440 kernel/params.c:986 do_one_initcall+0x105/0x630 init/main.c:1232 do_initcall_level init/main.c:1294 [inline] do_initcalls init/main.c:1310 [inline] do_basic_setup init/main.c:1329 [inline] kernel_init_freeable+0x649/0xb90 init/main.c:1546 kernel_init+0x1e/0x2c0 init/main.c:1437 page_owner free stack trace missing Memory state around the buggy address: ffff88810eb98580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88810eb98600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88810eb98680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88810eb98700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88810eb98780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to change bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup