syzbot has found a reproducer for the following issue on: HEAD commit: 2ccbdf43d5e7 Merge tag 'for-linus' of git://git.kernel.org.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10d61bca980000 kernel config: https://syzkaller.appspot.com/x/.config?x=b8786f381e62940f 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 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=125874ea980000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-2ccbdf43.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c40c1cd990d2/vmlinux-2ccbdf43.xz kernel image: https://storage.googleapis.com/syzbot-assets/a2a94050804e/bzImage-2ccbdf43.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:1131 Free of addr ffff888025dce280 by task kworker/u33:6/5317 CPU: 2 PID: 5317 Comm: kworker/u33:6 Not tainted 6.10.0-rc3-syzkaller-00044-g2ccbdf43d5e7 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Workqueue: hci0 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+0x135/0x160 mm/kasan/common.c:232 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2196 [inline] slab_free mm/slub.c:4437 [inline] kmem_cache_free+0x12f/0x3a0 mm/slub.c:4512 kfree_skbmem+0x10e/0x200 net/core/skbuff.c:1131 __kfree_skb net/core/skbuff.c:1188 [inline] kfree_skb_reason+0x138/0x210 net/core/skbuff.c:1223 kfree_skb include/linux/skbuff.h:1257 [inline] hci_req_sync_complete+0x16c/0x270 net/bluetooth/hci_request.c:109 hci_event_packet+0x963/0x1170 net/bluetooth/hci_event.c:7479 hci_rx_work+0x2c4/0x1610 net/bluetooth/hci_core.c:4074 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 5317: 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:3941 [inline] slab_alloc_node mm/slub.c:4001 [inline] kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4008 skb_clone+0x190/0x3f0 net/core/skbuff.c:2052 hci_send_cmd_sync net/bluetooth/hci_core.c:4123 [inline] hci_cmd_work+0x66a/0x710 net/bluetooth/hci_core.c:4143 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 5306: 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+0xf7/0x160 mm/kasan/common.c:240 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2196 [inline] slab_free mm/slub.c:4437 [inline] kmem_cache_free+0x12f/0x3a0 mm/slub.c:4512 kfree_skbmem+0x10e/0x200 net/core/skbuff.c:1131 __kfree_skb net/core/skbuff.c:1188 [inline] kfree_skb_reason+0x138/0x210 net/core/skbuff.c:1223 kfree_skb include/linux/skbuff.h:1257 [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+0x634/0x960 net/bluetooth/hci_core.c:787 hci_sock_ioctl+0x4f3/0x880 net/bluetooth/hci_sock.c:1150 sock_do_ioctl+0x116/0x280 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:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888025dce280 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 0 bytes inside of 240-byte region [ffff888025dce280, ffff888025dce370) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25dce head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 00fff00000000040 ffff888018ed8780 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080190019 00000001ffffefff 0000000000000000 head: 00fff00000000040 ffff888018ed8780 dead000000000122 0000000000000000 head: 0000000000000000 0000000080190019 00000001ffffefff 0000000000000000 head: 00fff00000000001 ffffea0000977381 ffffffffffffffff 0000000000000000 head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 5306, tgid 5306 (syz-executor.3), ts 70131626595, free_ts 69503653671 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1468 prep_new_page mm/page_alloc.c:1476 [inline] get_page_from_freelist+0x136a/0x2e50 mm/page_alloc.c:3420 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4678 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x56/0x110 mm/slub.c:2265 allocate_slab mm/slub.c:2428 [inline] new_slab+0x84/0x260 mm/slub.c:2481 ___slab_alloc+0xdac/0x1870 mm/slub.c:3667 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3757 __slab_alloc_node mm/slub.c:3810 [inline] slab_alloc_node mm/slub.c:3989 [inline] kmem_cache_alloc_node_noprof+0xed/0x310 mm/slub.c:4044 __alloc_skb+0x2b1/0x380 net/core/skbuff.c:656 alloc_skb include/linux/skbuff.h:1308 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:489 [inline] hci_prepare_cmd+0x32/0x2b0 net/bluetooth/hci_request.c:221 hci_req_add_ev+0x11b/0x2b0 net/bluetooth/hci_request.c:255 hci_scan_req+0x87/0x150 net/bluetooth/hci_core.c:73 __hci_req_sync+0x142/0x980 net/bluetooth/hci_request.c:130 hci_req_sync+0x97/0xd0 net/bluetooth/hci_request.c:206 hci_dev_cmd+0x634/0x960 net/bluetooth/hci_core.c:787 hci_sock_ioctl+0x4f3/0x880 net/bluetooth/hci_sock.c:1150 page last free pid 4688 tgid 4688 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1088 [inline] free_unref_page+0x64a/0xe40 mm/page_alloc.c:2583 __put_partials+0x14c/0x170 mm/slub.c:2995 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3941 [inline] slab_alloc_node mm/slub.c:4001 [inline] kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4008 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139 getname_flags+0x9b/0xf0 include/linux/audit.h:322 vfs_fstatat+0x9a/0x150 fs/stat.c:303 __do_sys_newfstatat+0xa6/0x130 fs/stat.c:468 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888025dce180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888025dce200: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff888025dce280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888025dce300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff888025dce380: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ================================================================== --- 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.
