================================================================== BUG: KASAN: use-after-free in hci_cmd_timeout+0x1cf/0x1e0 net/bluetooth/hci_core.c:1456 Read of size 2 at addr ffff88807e515b78 by task kworker/u5:4/4253 CPU: 1 PID: 4253 Comm: kworker/u5:4 Not tainted 6.1.116-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci0 hci_cmd_timeout Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 hci_cmd_timeout+0x1cf/0x1e0 net/bluetooth/hci_core.c:1456 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 4253: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422 skb_clone+0x1e5/0x360 net/core/skbuff.c:1660 hci_send_cmd_sync net/bluetooth/hci_core.c:4149 [inline] hci_cmd_work+0x296/0x660 net/bluetooth/hci_core.c:4169 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Freed by task 4403: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] kmem_cache_free+0x292/0x510 mm/slub.c:3683 kfree_skb include/linux/skbuff.h:1220 [inline] __hci_req_sync+0x626/0x940 net/bluetooth/hci_request.c:184 hci_req_sync+0xa5/0xc0 net/bluetooth/hci_request.c:206 hci_inquiry+0x443/0x860 net/bluetooth/hci_core.c:381 sock_do_ioctl+0x152/0x450 net/socket.c:1204 sock_ioctl+0x47f/0x770 net/socket.c:1321 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88807e515b40 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 56 bytes inside of 240-byte region [ffff88807e515b40, ffff88807e515c30) The buggy address belongs to the physical page: page:ffffea0001f94540 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e515 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea00009a8040 dead000000000002 ffff888019243000 raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 3625, tgid 3625 (udevd), ts 17188445130, free_ts 17161977769 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517 prep_new_page mm/page_alloc.c:2524 [inline] get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4313 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5589 alloc_slab_page+0x6a/0x150 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x84/0x2d0 mm/slub.c:1992 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] kmem_cache_alloc_node+0x1cf/0x310 mm/slub.c:3443 __alloc_skb+0xde/0x670 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1271 [inline] alloc_skb_with_frags+0xa4/0x740 net/core/skbuff.c:6162 sock_alloc_send_pskb+0x915/0xa50 net/core/sock.c:2747 unix_dgram_sendmsg+0x5b1/0x2050 net/unix/af_unix.c:1918 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] sock_write_iter+0x394/0x4e0 net/socket.c:1143 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x857/0xbc0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1444 [inline] free_pcp_prepare mm/page_alloc.c:1494 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464 free_slab mm/slub.c:2031 [inline] discard_slab mm/slub.c:2037 [inline] __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586 put_cpu_partial+0x17b/0x250 mm/slub.c:2662 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422 getname_flags+0xb8/0x4f0 fs/namei.c:139 do_sys_openat2+0xd2/0x4f0 fs/open.c:1312 do_sys_open fs/open.c:1334 [inline] __do_sys_openat fs/open.c:1350 [inline] __se_sys_openat fs/open.c:1345 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1345 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88807e515a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e515a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc >ffff88807e515b00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff88807e515b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e515c00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ==================================================================