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X-Mailer: git-send-email 2.55.0 In-Reply-To: <6a923059.1d9ded08.62e62.00fa.GAE@google.com> References: <6a923059.1d9ded08.62e62.00fa.GAE@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Sat, Aug 29, 01:05, syzbot wrote: >================================================================== >BUG: KASAN: slab-use-after-free in atkbd_event_work+0x592/0x650 drivers/input/keyboard/atkbd.c:-1 >Read of size 4 at addr ffff888025c96164 by task kworker/1:2/3686 > >CPU: 1 UID: 0 PID: 3686 Comm: kworker/1:2 Not tainted syzkaller >0 PREEMPT(full) >Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 >Workqueue: events atkbd_event_work >Call Trace: > > dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 > print_address_description+0x55/0x1e0 mm/kasan/report.c:378 > print_report+0x58/0x70 mm/kasan/report.c:482 > kasan_report+0x117/0x150 mm/kasan/report.c:595 > atkbd_event_work+0x592/0x650 drivers/input/keyboard/atkbd.c:-1 > process_one_work kernel/workqueue.c:3387 [inline] > process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470 > worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551 > kthread+0x38b/0x480 kernel/kthread.c:436 > ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 > > >Allocated by task 5621: > kasan_save_stack mm/kasan/common.c:57 [inline] > kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 > poison_kmalloc_redzone mm/kasan/common.c:398 [inline] > __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 > kasan_kmalloc include/linux/kasan.h:263 [inline] > __kmalloc_cache_noprof+0x321/0x600 mm/slub.c:5563 > _kmalloc_noprof include/linux/slab.h:991 [inline] > _kzalloc_noprof include/linux/slab.h:1312 [inline] > input_allocate_device+0x4e/0x2a0 drivers/input/input.c:1960 > atkbd_connect+0xb1/0x9c0 drivers/input/keyboard/atkbd.c:1258 > serio_connect_driver drivers/input/serio/serio.c:44 [inline] > serio_driver_probe+0x82/0xa0 drivers/input/serio/serio.c:748 > call_driver_probe drivers/base/dd.c:-1 [inline] > really_probe+0x254/0xae0 drivers/base/dd.c:706 > __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868 > driver_probe_device+0x4f/0x240 drivers/base/dd.c:898 > __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026 > bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 > __device_attach+0x2c4/0x450 drivers/base/dd.c:1098 > device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153 > bus_probe_device+0x12a/0x220 drivers/base/bus.c:620 > device_add+0x7d7/0xb80 drivers/base/core.c:3776 > serio_add_port drivers/input/serio/serio.c:512 [inline] > serio_handle_event+0x9f2/0xd20 drivers/input/serio/serio.c:197 > process_one_work kernel/workqueue.c:3387 [inline] > process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470 > worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551 > kthread+0x38b/0x480 kernel/kthread.c:436 > ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 > >Freed by task 8139: > kasan_save_stack mm/kasan/common.c:57 [inline] > kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 > kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 > poison_slab_object mm/kasan/common.c:253 [inline] > __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 > kasan_slab_free include/linux/kasan.h:235 [inline] > slab_free_hook mm/slub.c:2748 [inline] > slab_free mm/slub.c:6499 [inline] > kfree+0x1c5/0x650 mm/slub.c:6792 > input_dev_release+0xab/0xc0 drivers/input/input.c:1644 > device_release+0xc4/0x1f0 drivers/base/core.c:-1 > kobject_cleanup lib/kobject.c:689 [inline] > kobject_release lib/kobject.c:720 [inline] > kref_put include/linux/kref.h:65 [inline] > kobject_put+0x222/0x550 lib/kobject.c:737 > atkbd_disconnect+0xb5/0x110 drivers/input/keyboard/atkbd.c:966 > serio_disconnect_driver drivers/input/serio/serio.c:62 [inline] > serio_driver_remove+0x85/0xa0 drivers/input/serio/serio.c:755 > device_remove drivers/base/dd.c:616 [inline] > __device_release_driver drivers/base/dd.c:1349 [inline] > device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372 > serio_disconnect_port drivers/input/serio/serio.c:646 [inline] > serio_unregister_port+0x128/0x150 drivers/input/serio/serio.c:679 > userio_char_release+0x80/0xc0 drivers/input/serio/userio.c:105 > __fput+0x418/0xa50 fs/file_table.c:512 > task_work_run+0x1d9/0x270 kernel/task_work.c:233 > resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] > __exit_to_user_mode_loop kernel/entry/common.c:70 [inline] > exit_to_user_mode_loop+0x204/0x770 kernel/entry/common.c:101 > __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] > syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] > syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline] > do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > >The buggy address belongs to the object at ffff888025c96000 > which belongs to the cache kmalloc-4k of size 4096 >The buggy address is located 356 bytes inside of > freed 4096-byte region [ffff888025c96000, ffff888025c97000) > >The buggy address belongs to the physical page: >page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25c90 >head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 >flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) >page_type: f5(slab) >raw: 00fff00000000040 ffff88801b042140 dead000000000100 dead000000000122 >raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000 >head: 00fff00000000040 ffff88801b042140 dead000000000100 dead000000000122 >head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000 >head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff >head: ffffffffffffffff 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4978, tgid 4978 (udevd), ts 44140195112 > set_page_owner include/linux/page_owner.h:33 [inline] > post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 > prep_new_page mm/page_alloc.c:1879 [inline] > get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943 > __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436 > alloc_slab_page mm/slub.c:3347 [inline] > allocate_slab+0x7d/0x620 mm/slub.c:3462 > new_slab mm/slub.c:3513 [inline] > refill_objects+0x2d5/0x350 mm/slub.c:7410 > refill_sheaf mm/slub.c:2885 [inline] > __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4774 > alloc_from_pcs mm/slub.c:4850 [inline] > slab_alloc_node mm/slub.c:4984 [inline] > __do_kmalloc_node mm/slub.c:5413 [inline] > __kmalloc_noprof+0x47b/0x720 mm/slub.c:5439 > _kmalloc_noprof include/linux/slab.h:995 [inline] > tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251 > tomoyo_get_realpath security/tomoyo/file.c:151 [inline] > tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776 > security_file_open+0xa9/0x240 security/security.c:2739 > do_dentry_open+0x4a0/0x1380 fs/open.c:973 > vfs_open+0x3b/0x340 fs/open.c:1101 > do_open fs/namei.c:4837 [inline] > path_openat+0x1443/0x1d60 fs/namei.c:5000 > do_file_open+0x23e/0x4a0 fs/namei.c:5029 > do_sys_openat2+0x115/0x200 fs/open.c:1417 > do_sys_open fs/open.c:1423 [inline] > __do_sys_openat fs/open.c:1439 [inline] > __se_sys_openat fs/open.c:1434 [inline] > __x64_sys_openat+0x138/0x170 fs/open.c:1434 >page last free pid 4981 tgid 4981 ts 44132500299 stack trace: > reset_page_owner include/linux/page_owner.h:26 [inline] > __free_pages_prepare mm/page_alloc.c:1418 [inline] > __free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962 > __slab_free+0x274/0x2c0 mm/slub.c:5815 > qlink_free mm/kasan/quarantine.c:163 [inline] > qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 > kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 > __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 > kasan_slab_alloc include/linux/kasan.h:253 [inline] > slab_post_alloc_hook mm/slub.c:4683 [inline] > slab_alloc_node mm/slub.c:4996 [inline] > __kmalloc_cache_noprof+0x29f/0x600 mm/slub.c:5559 > _kmalloc_noprof include/linux/slab.h:991 [inline] > _kzalloc_noprof include/linux/slab.h:1312 [inline] > kernfs_iop_get_link+0x66/0x6c0 fs/kernfs/symlink.c:137 > vfs_readlink+0x24a/0x540 fs/namei.c:6419 > do_readlinkat+0x218/0x510 fs/stat.c:583 > __do_sys_readlink fs/stat.c:605 [inline] > __se_sys_readlink fs/stat.c:602 [inline] > __x64_sys_readlink+0x7f/0x90 fs/stat.c:602 > do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] > do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > >Memory state around the buggy address: > ffff888025c96000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888025c96080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>ffff888025c96100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff888025c96180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888025c96200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >================================================================== I believe this is a similar issue as this one[1]. The solution may be the same too(?) [1]: https://lore.kernel.org/all/6a90d9ef.4d659fcc.734b4.0019.GAE@google.com/T/ Thanks, Jeffin.