syzbot


KASAN: use-after-free Read in skb_release_head_state

Status: upstream: reported on 2024/04/25 21:25
Reported-by: syzbot+08daa8cf5175eaf6ed58@syzkaller.appspotmail.com
First crash: 194d, last: 84d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in skb_release_head_state bluetooth 1 1396d 1392d 0/28 auto-closed as invalid on 2021/05/09 12:11
upstream KASAN: slab-use-after-free Read in skb_release_head_state bluetooth syz error error 135 56d 198d 0/28 upstream: reported syz repro on 2024/04/22 06:47

Sample crash report:
mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium
mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium
==================================================================
BUG: KASAN: use-after-free in skb_dst_drop include/net/dst.h:267 [inline]
BUG: KASAN: use-after-free in skb_release_head_state+0x35/0x230 net/core/skbuff.c:840
Read of size 8 at addr ffff888076f17698 by task syz.1.720/6207

CPU: 1 PID: 6207 Comm: syz.1.720 Not tainted 6.1.104-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 skb_dst_drop include/net/dst.h:267 [inline]
 skb_release_head_state+0x35/0x230 net/core/skbuff.c:840
 skb_release_all net/core/skbuff.c:854 [inline]
 __kfree_skb net/core/skbuff.c:870 [inline]
 kfree_skb_reason+0x13d/0x390 net/core/skbuff.c:893
 kfree_skb include/linux/skbuff.h:1220 [inline]
 __hci_req_sync+0x626/0x940 net/bluetooth/hci_request.c:184
 hci_req_sync+0xa5/0xc0 net/bluetooth/hci_request.c:206
 hci_inquiry+0x443/0x860 net/bluetooth/hci_core.c:381
 sock_do_ioctl+0x152/0x450 net/socket.c:1204
 sock_ioctl+0x47f/0x770 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f68ecb799f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f68ed98b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f68ecd15f80 RCX: 00007f68ecb799f9
RDX: 0000000020000000 RSI: 00000000800448f0 RDI: 000000000000000a
RBP: 00007f68ecbe78ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f68ecd15f80 R15: 00007ffc9d19c9a8
 </TASK>

Allocated by task 3646:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 skb_clone+0x1e5/0x360 net/core/skbuff.c:1660
 hci_send_cmd_sync net/bluetooth/hci_core.c:4146 [inline]
 hci_cmd_work+0x296/0x660 net/bluetooth/hci_core.c:4166
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 3656:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x292/0x510 mm/slub.c:3683
 kfree_skb include/linux/skbuff.h:1220 [inline]
 hci_send_cmd_sync net/bluetooth/hci_core.c:4145 [inline]
 hci_cmd_work+0x26b/0x660 net/bluetooth/hci_core.c:4166
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff888076f17640
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 88 bytes inside of
 240-byte region [ffff888076f17640, ffff888076f17730)

The buggy address belongs to the physical page:
page:ffffea0001dbc5c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x76f17
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea00008a9dc0 dead000000000002 ffff888015a43500
raw: 0000000000000000 00000000000c000c 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 0x12a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY), pid 3638, tgid 3638 (syz-executor), ts 67973160553, free_ts 67854664719
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x322e/0x33b0 mm/page_alloc.c:4290
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5558
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x1a5/0x2d0 mm/slub.c:3422
 skb_clone+0x1e5/0x360 net/core/skbuff.c:1660
 __netlink_deliver_tap_skb net/netlink/af_netlink.c:300 [inline]
 __netlink_deliver_tap+0x38d/0x770 net/netlink/af_netlink.c:325
 netlink_deliver_tap+0x19d/0x1b0 net/netlink/af_netlink.c:338
 netlink_deliver_tap_kernel net/netlink/af_netlink.c:347 [inline]
 netlink_unicast_kernel net/netlink/af_netlink.c:1325 [inline]
 netlink_unicast+0x7aa/0x970 net/netlink/af_netlink.c:1352
 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 __sys_sendto+0x480/0x600 net/socket.c:2148
 __do_sys_sendto net/socket.c:2160 [inline]
 __se_sys_sendto net/socket.c:2156 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2156
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 kmem_cache_alloc_node+0x136/0x310 mm/slub.c:3443
 __alloc_skb+0xde/0x670 net/core/skbuff.c:505
 alloc_skb include/linux/skbuff.h:1271 [inline]
 alloc_skb_with_frags+0xa4/0x740 net/core/skbuff.c:6168
 sock_alloc_send_pskb+0x915/0xa50 net/core/sock.c:2747
 sock_alloc_send_skb include/net/sock.h:1918 [inline]
 mld_newpack+0x1c0/0xa90 net/ipv6/mcast.c:1748
 add_grhead net/ipv6/mcast.c:1851 [inline]
 add_grec+0x1492/0x19a0 net/ipv6/mcast.c:1989
 mld_send_initial_cr+0x20f/0x3a0 net/ipv6/mcast.c:2236
 mld_dad_work+0x40/0x400 net/ipv6/mcast.c:2262
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439

Memory state around the buggy address:
 ffff888076f17580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff888076f17600: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
>ffff888076f17680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888076f17700: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
 ffff888076f17780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/13 18:25 linux-6.1.y 36790ef5e00b f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in skb_release_head_state
2024/07/16 04:26 linux-6.1.y cac15753b8ce e8709b21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in skb_release_head_state
2024/07/07 04:46 linux-6.1.y 7753af06eebf 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in skb_release_head_state
2024/07/02 17:36 linux-6.1.y 99e6a620de00 07f0a0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in skb_release_head_state
2024/04/25 21:25 linux-6.1.y 6741e066ec76 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf KASAN: use-after-free Read in skb_release_head_state
2024/06/27 10:43 linux-6.1.y eb44d83053d6 6ef39602 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in skb_release_head_state
2024/06/16 06:40 linux-6.1.y ae9f2a70d69e f429ab00 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in skb_release_head_state
2024/06/10 21:40 linux-6.1.y 88690811da69 048c640a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in skb_release_head_state
* Struck through repros no longer work on HEAD.