BUG: KASAN: slab-use-after-free in skb_end_pointer include/linux/skbuff.h:1636 [inline] BUG: KASAN: slab-use-after-free in skb_zcopy include/linux/skbuff.h:1697 [inline] BUG: KASAN: slab-use-after-free in skb_release_data+0x900/0x990 net/core/skbuff.c:1121 Read of size 8 at addr ffff88802b474490 by task syz-executor.1/5201 CPU: 3 PID: 5201 Comm: syz-executor.1 Not tainted 6.9.0-rc3-syzkaller-00344-g8f2c057754b2 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __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+0xd9/0x110 mm/kasan/report.c:601 skb_end_pointer include/linux/skbuff.h:1636 [inline] skb_zcopy include/linux/skbuff.h:1697 [inline] skb_release_data+0x900/0x990 net/core/skbuff.c:1121 skb_release_all net/core/skbuff.c:1202 [inline] __kfree_skb net/core/skbuff.c:1216 [inline] kfree_skb_reason+0x12d/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+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:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x193/0x220 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 RIP: 0033:0x7f6b0487dbcb Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007ffecc7beed0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f6b0487dbcb RDX: 00007ffecc7bef48 RSI: 00000000400448dd RDI: 0000000000000003 RBP: 0000555573d06430 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000002 R13: 0000000000000002 R14: 00007f6b049ac9d8 R15: 000000000000000c Allocated by task 5213: 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+0x9a9/0x1ac0 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c1/0x3a0 kernel/kthread.c:388 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 5214: 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_complete+0x16c/0x270 net/bluetooth/hci_request.c:109 hci_event_packet+0x963/0x1170 net/bluetooth/hci_event.c:7604 hci_rx_work+0x2c4/0x1610 net/bluetooth/hci_core.c:4171 process_one_work+0x9a9/0x1ac0 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff88802b4743c0 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 208 bytes inside of freed 240-byte region [ffff88802b4743c0, ffff88802b4744b0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b474 head: order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 00fff80000000840 ffff888019288780 0000000000000000 0000000000000001 raw: 0000000000000000 0000000000190019 00000001ffffffff 0000000000000000 head: 00fff80000000840 ffff888019288780 0000000000000000 0000000000000001 head: 0000000000000000 0000000000190019 00000001ffffffff 0000000000000000 head: 00fff80000000001 ffffea0000ad1d01 dead000000000122 00000000ffffffff head: 0000000200000000 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4905, tgid 4905 (dhcpcd), ts 28556508976, free_ts 28440797003 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+0x50a/0x5c0 net/socket.c:1160 call_write_iter include/linux/fs.h:2110 [inline] do_iter_readv_writev+0x504/0x780 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 5046 tgid 5046 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 __put_partials+0x14c/0x170 mm/slub.c:2906 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:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc+0x136/0x320 mm/slub.c:3852 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+0x98/0x120 fs/stat.c:468 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 Memory state around the buggy address: ffff88802b474380: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff88802b474400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802b474480: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ^ ffff88802b474500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802b474580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ==================================================================