================================================================== BUG: KASAN: slab-out-of-bounds in __lock_acquire+0x3c88/0x5230 kernel/locking/lockdep.c:4772 Read of size 8 at addr ffff8881951370a0 by task kworker/1:3/4824 CPU: 1 PID: 4824 Comm: kworker/1:3 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:436 __lock_acquire+0x3c88/0x5230 kernel/locking/lockdep.c:4772 lock_acquire kernel/locking/lockdep.c:5512 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:359 [inline] lock_sock_nested+0x40/0x120 net/core/sock.c:3057 l2cap_sock_teardown_cb+0xa1/0x660 net/bluetooth/l2cap_sock.c:1528 l2cap_chan_del+0xbc/0xa80 net/bluetooth/l2cap_core.c:622 l2cap_chan_close+0x1bc/0xaf0 net/bluetooth/l2cap_core.c:825 l2cap_chan_timeout+0x17e/0x2f0 net/bluetooth/l2cap_core.c:436 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Allocated by task 0: (stack is not available) Freed by task 4824: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357 ____kasan_slab_free mm/kasan/common.c:360 [inline] ____kasan_slab_free mm/kasan/common.c:325 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:212 [inline] slab_free_hook mm/slub.c:1581 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1606 slab_free mm/slub.c:3166 [inline] kfree+0xe5/0x7f0 mm/slub.c:4225 skb_free_head net/core/skbuff.c:651 [inline] skb_release_data+0x622/0x750 net/core/skbuff.c:672 skb_release_all net/core/skbuff.c:726 [inline] __kfree_skb net/core/skbuff.c:740 [inline] consume_skb net/core/skbuff.c:896 [inline] consume_skb+0xc2/0x160 net/core/skbuff.c:890 nsim_dev_trap_report drivers/net/netdevsim/dev.c:586 [inline] nsim_dev_trap_report_work+0x86f/0xbd0 drivers/net/netdevsim/dev.c:611 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 The buggy address belongs to the object at ffff888195136000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 160 bytes to the right of 4096-byte region [ffff888195136000, ffff888195137000) The buggy address belongs to the page: page:ffffea0006544c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x195130 head:ffffea0006544c00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x57ff00000010200(slab|head|node=1|zone=2|lastcpupid=0x7ff) raw: 057ff00000010200 dead000000000100 dead000000000122 ffff888011042140 raw: 0000000000000000 0000000000040004 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 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4824, ts 702691334417, free_ts 701834147872 prep_new_page mm/page_alloc.c:2358 [inline] get_page_from_freelist+0x1033/0x2b60 mm/page_alloc.c:3994 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5200 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1644 [inline] allocate_slab+0x2c5/0x4c0 mm/slub.c:1784 new_slab mm/slub.c:1847 [inline] new_slab_objects mm/slub.c:2593 [inline] ___slab_alloc+0x44c/0x7a0 mm/slub.c:2756 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2796 slab_alloc_node mm/slub.c:2878 [inline] __kmalloc_node_track_caller+0x2e6/0x350 mm/slub.c:4604 kmalloc_reserve net/core/skbuff.c:354 [inline] __alloc_skb+0xde/0x340 net/core/skbuff.c:425 alloc_skb include/linux/skbuff.h:1107 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:513 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:570 [inline] nsim_dev_trap_report_work+0x2ac/0xbd0 drivers/net/netdevsim/dev.c:611 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1298 [inline] __free_pages_ok+0x476/0xce0 mm/page_alloc.c:1572 unfreeze_partials+0x16c/0x1b0 mm/slub.c:2374 put_cpu_partial+0x13d/0x230 mm/slub.c:2410 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x8e/0xa0 mm/kasan/common.c:438 kasan_slab_alloc include/linux/kasan.h:236 [inline] slab_post_alloc_hook mm/slab.h:524 [inline] slab_alloc_node mm/slub.c:2912 [inline] slab_alloc mm/slub.c:2920 [inline] kmem_cache_alloc+0x219/0x3a0 mm/slub.c:2925 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags fs/namei.c:2734 [inline] user_path_at_empty+0xa1/0x100 fs/namei.c:2734 do_readlinkat+0xcd/0x2f0 fs/stat.c:425 __do_sys_readlinkat fs/stat.c:452 [inline] __se_sys_readlinkat fs/stat.c:449 [inline] __x64_sys_readlinkat+0x93/0xf0 fs/stat.c:449 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff888195136f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888195137000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888195137080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888195137100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888195137180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================