Hello, syzbot found the following issue on: HEAD commit: 7271b2a53042 Add linux-next specific files for 20230818 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=13404b6ba80000 kernel config: https://syzkaller.appspot.com/x/.config?x=1936af09cdef7dd6 dashboard link: https://syzkaller.appspot.com/bug?extid=a0c80b06ae2cb8895bc4 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13506923a80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=147569efa80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/d81109bc02c1/disk-7271b2a5.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/4b3bf8e2a4f7/vmlinux-7271b2a5.xz kernel image: https://storage.googleapis.com/syzbot-assets/6404cd473c1e/bzImage-7271b2a5.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a0c80b06ae2cb8895bc4@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in hci_send_acl+0xdf4/0xf30 net/bluetooth/hci_core.c:3228 Read of size 8 at addr ffff888025635618 by task kworker/1:1/27 CPU: 1 PID: 27 Comm: kworker/1:1 Not tainted 6.5.0-rc6-next-20230818-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: events l2cap_info_timeout Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 hci_send_acl+0xdf4/0xf30 net/bluetooth/hci_core.c:3228 l2cap_send_cmd+0x6dd/0x920 net/bluetooth/l2cap_core.c:977 l2cap_send_conn_req+0x1e5/0x260 net/bluetooth/l2cap_core.c:1286 l2cap_start_connection+0x11e/0x420 net/bluetooth/l2cap_core.c:1514 l2cap_conn_start+0x7ae/0xa40 net/bluetooth/l2cap_core.c:1661 process_one_work+0x887/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8bb/0x1290 kernel/workqueue.c:2784 kthread+0x33a/0x430 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 </TASK> Allocated by task 5046: kasan_save_stack+0x33/0x50 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+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] hci_chan_create+0xa6/0x3a0 net/bluetooth/hci_conn.c:2691 l2cap_conn_add.part.0+0x1a/0xdf0 net/bluetooth/l2cap_core.c:7841 l2cap_conn_add include/net/bluetooth/l2cap.h:866 [inline] l2cap_chan_connect+0x15b9/0x2140 net/bluetooth/l2cap_core.c:8053 bt_6lowpan_connect net/bluetooth/6lowpan.c:894 [inline] lowpan_control_write+0x3d6/0x730 net/bluetooth/6lowpan.c:1129 full_proxy_write+0x124/0x190 fs/debugfs/file.c:236 vfs_write+0x2a4/0xe40 fs/read_write.c:582 ksys_write+0x12f/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 50: kasan_save_stack+0x33/0x50 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:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3822 hci_chan_list_flush+0x81/0xf0 net/bluetooth/hci_conn.c:2731 hci_conn_cleanup net/bluetooth/hci_conn.c:152 [inline] hci_conn_del+0x1fc/0xd10 net/bluetooth/hci_conn.c:1140 hci_abort_conn_sync+0xacb/0xe20 net/bluetooth/hci_sync.c:5432 abort_conn_sync+0x18e/0x3a0 net/bluetooth/hci_conn.c:2878 hci_cmd_sync_work+0x1a4/0x3c0 net/bluetooth/hci_sync.c:306 process_one_work+0x887/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8bb/0x1290 kernel/workqueue.c:2784 kthread+0x33a/0x430 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3373 kernfs_unlink_open_file+0x3b6/0x4b0 fs/kernfs/file.c:633 kernfs_fop_release+0xec/0x1e0 fs/kernfs/file.c:805 __fput+0x3f7/0xa70 fs/file_table.c:384 __fput_sync+0x47/0x50 fs/file_table.c:465 __do_sys_close fs/open.c:1572 [inline] __se_sys_close fs/open.c:1557 [inline] __x64_sys_close+0x87/0xf0 fs/open.c:1557 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3373 kernfs_unlink_open_file+0x3b6/0x4b0 fs/kernfs/file.c:633 kernfs_fop_release+0xec/0x1e0 fs/kernfs/file.c:805 __fput+0x3f7/0xa70 fs/file_table.c:384 __fput_sync+0x47/0x50 fs/file_table.c:465 __do_sys_close fs/open.c:1572 [inline] __se_sys_close fs/open.c:1557 [inline] __x64_sys_close+0x87/0xf0 fs/open.c:1557 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888025635600 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 24 bytes inside of freed 128-byte region [ffff888025635600, ffff888025635680) The buggy address belongs to the physical page: page:ffffea0000958d40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25635 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888012c418c0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 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 4500, tgid 4500 (udevd), ts 28013160887, free_ts 27864795775 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0x10d7/0x31b0 mm/page_alloc.c:3219 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4475 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2298 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8be/0x1570 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x137/0x350 mm/slub.c:3517 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1095 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] kernfs_get_open_node fs/kernfs/file.c:572 [inline] kernfs_fop_open+0xad1/0xe00 fs/kernfs/file.c:740 do_dentry_open+0x88b/0x1730 fs/open.c:929 do_open fs/namei.c:3636 [inline] path_openat+0x19af/0x29c0 fs/namei.c:3793 do_filp_open+0x1de/0x430 fs/namei.c:3820 do_sys_openat2+0x176/0x1e0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2348 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2441 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x18b/0x1d0 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x172/0x3b0 mm/slub.c:3502 getname_flags.part.0+0x50/0x4d0 fs/namei.c:140 getname_flags include/linux/audit.h:319 [inline] getname+0x90/0xe0 fs/namei.c:219 do_sys_openat2+0x100/0x1e0 fs/open.c:1416 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888025635500: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc ffff888025635580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888025635600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888025635680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888025635700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- 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 overwrite 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
