Hello, syzbot found the following issue on: HEAD commit: 66ad4829ddd0 Merge tag 'net-6.10-rc1' of git://git.kernel... git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=149350d8980000 kernel config: https://syzkaller.appspot.com/x/.config?x=48c05addbb27f3b0 dashboard link: https://syzkaller.appspot.com/bug?extid=542cd57c45c01d9c33f8 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/32f7723d467f/disk-66ad4829.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/2cb82a76d362/vmlinux-66ad4829.xz kernel image: https://storage.googleapis.com/syzbot-assets/07340808386b/bzImage-66ad4829.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+542cd57c45c01d9c33f8@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in l2cap_sock_ready_cb+0xd7/0x140 net/bluetooth/l2cap_sock.c:1662 Read of size 8 at addr ffff88806c4de188 by task kworker/1:1/17633 CPU: 1 PID: 17633 Comm: kworker/1:1 Not tainted 6.9.0-syzkaller-12071-g66ad4829ddd0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: events l2cap_info_timeout Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 l2cap_sock_ready_cb+0xd7/0x140 net/bluetooth/l2cap_sock.c:1662 l2cap_chan_ready net/bluetooth/l2cap_core.c:1256 [inline] l2cap_conn_start+0x8db/0x1140 net/bluetooth/l2cap_core.c:1506 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 27936: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:4121 [inline] __kmalloc_noprof+0x1f9/0x400 mm/slub.c:4134 kmalloc_noprof include/linux/slab.h:664 [inline] sk_prot_alloc+0xe0/0x210 net/core/sock.c:2080 sk_alloc+0x38/0x370 net/core/sock.c:2133 bt_sock_alloc+0x3c/0x340 net/bluetooth/af_bluetooth.c:148 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1869 [inline] l2cap_sock_create+0x13f/0x2d0 net/bluetooth/l2cap_sock.c:1909 bt_sock_create+0x161/0x230 net/bluetooth/af_bluetooth.c:132 __sock_create+0x490/0x920 net/socket.c:1571 sock_create net/socket.c:1622 [inline] __sys_socket_create net/socket.c:1659 [inline] __sys_socket+0x150/0x3c0 net/socket.c:1706 __do_sys_socket net/socket.c:1720 [inline] __se_sys_socket net/socket.c:1718 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1718 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 27935: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2195 [inline] slab_free mm/slub.c:4436 [inline] kfree+0x149/0x360 mm/slub.c:4557 sk_prot_free net/core/sock.c:2116 [inline] __sk_destruct+0x476/0x5f0 net/core/sock.c:2208 l2cap_sock_release+0x15b/0x1d0 net/bluetooth/l2cap_sock.c:1417 __sock_release net/socket.c:659 [inline] sock_close+0xbc/0x240 net/socket.c:1421 __fput+0x406/0x8b0 fs/file_table.c:422 __do_sys_close fs/open.c:1555 [inline] __se_sys_close fs/open.c:1540 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1540 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88806c4de000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 392 bytes inside of freed 2048-byte region [ffff88806c4de000, ffff88806c4de800) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6c4d8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 00fff00000000040 ffff888015042000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 00000001ffffefff 0000000000000000 head: 00fff00000000040 ffff888015042000 0000000000000000 dead000000000001 head: 0000000000000000 0000000000080008 00000001ffffefff 0000000000000000 head: 00fff00000000003 ffffea0001b13601 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 26413, tgid 26413 (syz-executor.2), ts 1938838512727, free_ts 1929373430793 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468 prep_new_page mm/page_alloc.c:1476 [inline] get_page_from_freelist+0x2e2d/0x2ee0 mm/page_alloc.c:3402 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4660 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2264 allocate_slab+0x5a/0x2e0 mm/slub.c:2427 new_slab mm/slub.c:2480 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3666 __slab_alloc+0x58/0xa0 mm/slub.c:3756 __slab_alloc_node mm/slub.c:3809 [inline] slab_alloc_node mm/slub.c:3988 [inline] __do_kmalloc_node mm/slub.c:4120 [inline] kmalloc_node_track_caller_noprof+0x281/0x440 mm/slub.c:4141 kmemdup_noprof+0x2a/0x60 mm/util.c:131 ip_vs_control_net_init_sysctl net/netfilter/ipvs/ip_vs_ctl.c:4284 [inline] ip_vs_control_net_init+0x7da/0x17f0 net/netfilter/ipvs/ip_vs_ctl.c:4463 __ip_vs_init+0x2d2/0x460 net/netfilter/ipvs/ip_vs_core.c:2308 ops_init+0x359/0x610 net/core/net_namespace.c:139 setup_net+0x515/0xca0 net/core/net_namespace.c:343 copy_net_ns+0x4e2/0x7b0 net/core/net_namespace.c:508 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 page last free pid 26200 tgid 26200 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1088 [inline] free_unref_page+0xd22/0xea0 mm/page_alloc.c:2565 vfree+0x186/0x2e0 mm/vmalloc.c:3346 kcov_put kernel/kcov.c:429 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:525 __fput+0x406/0x8b0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa27/0x27e0 kernel/exit.c:874 do_group_exit+0x207/0x2c0 kernel/exit.c:1023 get_signal+0x16a1/0x1740 kernel/signal.c:2909 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88806c4de080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806c4de100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806c4de180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806c4de200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806c4de280: fb 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 report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
