Hello, syzbot found the following issue on: HEAD commit: dbe0a7be2838 Merge tag 'thermal-6.9-rc5' of git://git.kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1797a520980000 kernel config: https://syzkaller.appspot.com/x/.config?x=c5d33c579b4e833f dashboard link: https://syzkaller.appspot.com/bug?extid=35ebc808442df6420eae compiler: gcc (Debian 12.2.0-14) 12.2.0, 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/533abb2e04bb/disk-dbe0a7be.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/bab25bf1664b/vmlinux-dbe0a7be.xz kernel image: https://storage.googleapis.com/syzbot-assets/a86e1d3d98aa/bzImage-dbe0a7be.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+35ebc808442df6420eae@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: double-free in kfree_skbmem+0x10e/0x200 net/core/skbuff.c:1159 Free of addr ffff8880114bcdc0 by task kworker/u9:0/52 CPU: 1 PID: 52 Comm: kworker/u9:0 Not tainted 6.9.0-rc4-syzkaller-00164-gdbe0a7be2838 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: hci4 hci_rx_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report_invalid_free+0xaa/0xd0 mm/kasan/report.c:563 poison_slab_object mm/kasan/common.c:232 [inline] __kasan_slab_free+0x16b/0x1a0 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2106 [inline] slab_free mm/slub.c:4280 [inline] kmem_cache_free+0x12e/0x380 mm/slub.c:4344 kfree_skbmem+0x10e/0x200 net/core/skbuff.c:1159 __kfree_skb net/core/skbuff.c:1217 [inline] kfree_skb_reason+0x13a/0x210 net/core/skbuff.c:1252 kfree_skb include/linux/skbuff.h:1262 [inline] hci_req_sync_complete+0x16c/0x270 net/bluetooth/hci_request.c:109 hci_event_packet+0x966/0x1170 net/bluetooth/hci_event.c:7604 hci_rx_work+0x2c4/0x1610 net/bluetooth/hci_core.c:4171 process_one_work+0x9ac/0x1ac0 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c4/0x3a0 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 52: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc+0x136/0x320 mm/slub.c:3852 skb_clone+0x190/0x3f0 net/core/skbuff.c:2063 hci_send_cmd_sync net/bluetooth/hci_core.c:4220 [inline] hci_cmd_work+0x66a/0x710 net/bluetooth/hci_core.c:4240 process_one_work+0x9ac/0x1ac0 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c4/0x3a0 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 10076: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:240 [inline] __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2106 [inline] slab_free mm/slub.c:4280 [inline] kmem_cache_free+0x12e/0x380 mm/slub.c:4344 kfree_skbmem+0x10e/0x200 net/core/skbuff.c:1159 __kfree_skb net/core/skbuff.c:1217 [inline] kfree_skb_reason+0x13a/0x210 net/core/skbuff.c:1252 kfree_skb include/linux/skbuff.h:1262 [inline] __hci_req_sync+0x61d/0x980 net/bluetooth/hci_request.c:184 hci_req_sync+0x97/0xd0 net/bluetooth/hci_request.c:206 hci_dev_cmd+0x653/0x9c0 net/bluetooth/hci_core.c:790 hci_sock_ioctl+0x4f3/0x8e0 net/bluetooth/hci_sock.c:1153 sock_do_ioctl+0x119/0x280 net/socket.c:1222 sock_ioctl+0x22e/0x6c0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x196/0x220 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880114bcdc0 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 0 bytes inside of 240-byte region [ffff8880114bcdc0, ffff8880114bceb0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x114bc flags: 0xfff80000000800(slab|node=0|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 00fff80000000800 ffff888018ad6780 ffffea000183fd00 dead000000000002 raw: 0000000000000000 00000000800c000c 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 4748, tgid 666454001 (dhcpcd), ts 4748, free_ts 597626032748 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page mm/slub.c:2175 [inline] allocate_slab mm/slub.c:2338 [inline] new_slab+0xcc/0x3a0 mm/slub.c:2391 ___slab_alloc+0x66d/0x1790 mm/slub.c:3525 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3610 __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] kmem_cache_alloc_node+0x10a/0x340 mm/slub.c:3888 __alloc_skb+0x2b1/0x380 net/core/skbuff.c:658 alloc_skb include/linux/skbuff.h:1313 [inline] alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6504 sock_alloc_send_pskb+0x7f1/0x980 net/core/sock.c:2795 unix_dgram_sendmsg+0x4b9/0x1b10 net/unix/af_unix.c:2019 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x50d/0x5c0 net/socket.c:1160 call_write_iter include/linux/fs.h:2110 [inline] do_iter_readv_writev+0x507/0x780 fs/read_write.c:741 vfs_writev+0x36f/0xdb0 fs/read_write.c:971 do_writev+0x287/0x370 fs/read_write.c:1018 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 page last free pid 8963 tgid 8961 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1141 [inline] free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487 tlb_batch_list_free mm/mmu_gather.c:159 [inline] tlb_finish_mmu+0x237/0x7b0 mm/mmu_gather.c:468 exit_mmap+0x3da/0xb90 mm/mmap.c:3280 __mmput+0x12a/0x4d0 kernel/fork.c:1346 mmput+0x62/0x70 kernel/fork.c:1368 exit_mm kernel/exit.c:569 [inline] do_exit+0x999/0x2c10 kernel/exit.c:865 do_group_exit+0xd3/0x2a0 kernel/exit.c:1027 get_signal+0x2616/0x2710 kernel/signal.c:2911 arch_do_signal_or_restart+0x90/0x7e0 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+0x14a/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xdc/0x260 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8880114bcc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880114bcd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc >ffff8880114bcd80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff8880114bce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880114bce80: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ================================================================== --- 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
