KASAN: slab-out-of-bounds Read in hci_sock_setsockopt

Status: upstream: reported C repro on 2026/02/17 09:12
Bug presence: origin:lts
[Documentation on labels]
Reported-by: syzbot+badc3c56f2aa7037b3b0@syzkaller.appspotmail.com
First crash: 261d, last: 8d20h
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2026/02/17 lts (merge base) e45d5d41c134 C [report] KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 upstream (ToT) 970296997869 C Didn't crash
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in hci_sock_setsockopt bluetooth 17 syz, C done unreliable 5 939d 944d 0/29 auto-obsoleted due to no activity on 2024/07/19 03:49
▶ ▼ Last patch testing requests (8)
Created Duration User Patch Repo Result
2026/08/29 19:40 20m retest repro android13-5.15-lts report job log log
2026/08/03 17:05 18m retest repro android13-5.15-lts report log
2026/08/03 17:05 13m retest repro android13-5.15-lts report log
2026/08/03 17:05 30m retest repro android13-5.15-lts report log
2026/08/03 17:05 31m retest repro android13-5.15-lts report log
2026/06/12 07:32 13m retest repro android13-5.15-lts log
2026/05/19 03:27 15m retest repro android13-5.15-lts log
2026/05/19 03:27 13m retest repro android13-5.15-lts log

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline]
BUG: KASAN: slab-out-of-bounds in hci_sock_setsockopt+0x7f5/0x820 net/bluetooth/hci_sock.c:1925
Read of size 4 at addr ffff8881187dee3b by task syz-executor196/303

CPU: 1 PID: 303 Comm: syz-executor196 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0x10f/0x150 mm/kasan/report.c:444
 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report_generic.c:319
 copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
 copy_from_sockptr include/linux/sockptr.h:55 [inline]
 hci_sock_setsockopt+0x7f5/0x820 net/bluetooth/hci_sock.c:1925
 __sys_setsockopt+0x2e9/0x470 net/socket.c:2203
 __do_sys_setsockopt net/socket.c:2214 [inline]
 __se_sys_setsockopt net/socket.c:2211 [inline]
 __x64_sys_setsockopt+0xbf/0xd0 net/socket.c:2211
 x64_sys_call+0x982/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:55
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe5b0232db9
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 0f 1f 44 00 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 d8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd7d378fa8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007ffd7d3790d8 RCX: 00007fe5b0232db9
RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 0000000000000001 R08: 0000000000000003 R09: 00007ffd7d3790d8
R10: 0000200000000040 R11: 0000000000000246 R12: 00007ffd7d3790c8
R13: 0000000000000002 R14: 00007fe5b02c3ca0 R15: 0000000000000002
 </TASK>

Allocated by task 303:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 ____kasan_kmalloc mm/kasan/common.c:512 [inline]
 __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:521
 kasan_kmalloc include/linux/kasan.h:227 [inline]
 __kmalloc+0x13d/0x2c0 mm/slub.c:4436
 kmalloc include/linux/slab.h:624 [inline]
 __cgroup_bpf_run_filter_setsockopt+0x8e7/0xaa0 kernel/bpf/cgroup.c:1511
 __sys_setsockopt+0x40e/0x470 net/socket.c:2186
 __do_sys_setsockopt net/socket.c:2214 [inline]
 __se_sys_setsockopt net/socket.c:2211 [inline]
 __x64_sys_setsockopt+0xbf/0xd0 net/socket.c:2211
 x64_sys_call+0x982/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:55
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff8881187dee38
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 3 bytes inside of
 8-byte region [ffff8881187dee38, ffff8881187dee40)
The buggy address belongs to the page:
page:ffffea000461f780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1187de
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 0000000000000000 dead000000000122 ffff888100042300
raw: 0000000000000000 0000000080660066 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 109, ts 4767537632, free_ts 4739948250
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2607
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2613
 get_page_from_freelist+0x2c3a/0x2cd0 mm/page_alloc.c:4487
 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5824
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1937 [inline]
 new_slab+0xa0/0x4d0 mm/slub.c:2000
 ___slab_alloc+0x3ac/0x840 mm/slub.c:3033
 __slab_alloc+0x49/0x90 mm/slub.c:3120
 slab_alloc_node mm/slub.c:3211 [inline]
 slab_alloc mm/slub.c:3255 [inline]
 __kmalloc_track_caller+0x169/0x2c0 mm/slub.c:4954
 kmemdup+0x26/0x60 mm/util.c:132
 shmem_symlink+0x163/0x4d0 mm/shmem.c:3098
 vfs_symlink+0x29e/0x470 fs/namei.c:4437
 do_symlinkat+0x24a/0x5d0 fs/namei.c:4466
 __do_sys_symlink fs/namei.c:4488 [inline]
 __se_sys_symlink fs/namei.c:4486 [inline]
 __x64_sys_symlink+0x7e/0x90 fs/namei.c:4486
 x64_sys_call+0x759/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:89
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1474 [inline]
 free_pcp_prepare mm/page_alloc.c:1546 [inline]
 free_unref_page_prepare+0x5fa/0x600 mm/page_alloc.c:3536
 free_unref_page_list+0x138/0x9e0 mm/page_alloc.c:3673
 release_pages+0x1264/0x12c0 mm/swap.c:1015
 free_pages_and_swap_cache+0x86/0xa0 mm/swap_state.c:320
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x17e/0x310 mm/mmu_gather.c:338
 exit_mmap+0x43b/0x8b0 mm/mmap.c:3248
 __mmput+0x92/0x300 kernel/fork.c:1191
 mmput+0x50/0x150 kernel/fork.c:1214
 exit_mm kernel/exit.c:561 [inline]
 do_exit+0xacc/0x29a0 kernel/exit.c:883
 do_group_exit+0x149/0x310 kernel/exit.c:1010
 __do_sys_exit_group kernel/exit.c:1021 [inline]
 __se_sys_exit_group kernel/exit.c:1019 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1019
 x64_sys_call+0x832/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Memory state around the buggy address:
 ffff8881187ded00: fc fc fc fc fc fc fc fc fc fa fc fc fc fc fc fc
 ffff8881187ded80: fc fc fc fa fc fc fc fc fa fc fc fc fc 00 fc fc
>ffff8881187dee00: fc fc fa fc fc fc fc 03 fc fc fc fc fa fc fc fc
                                        ^
 ffff8881187dee80: fc fc fc fc fc fc fa fc fc fc fc fc fc fc fc fc
 ffff8881187def00: fa fc fc fc fc fa fc fc fc fc 00 fc fc fc fc fc
==================================================================

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/17 23:07 android13-5.15-lts ff23d765b06f 432c0077 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 14:10 android13-5.15-lts 13d6d33696ef e439b951 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 13:01 android13-5.15-lts 13d6d33696ef e439b951 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 11:59 android13-5.15-lts 13d6d33696ef e439b951 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 10:14 android13-5.15-lts 13d6d33696ef e439b951 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 09:05 android13-5.15-lts 13d6d33696ef e439b951 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/10/27 13:48 android13-5.15-lts 2316d138a3c3 168cb7a2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 08:23 android13-5.15-lts 13d6d33696ef e439b951 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 08:12 android13-5.15-lts 13d6d33696ef e439b951 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
2026/02/17 07:41 android13-5.15-lts 13d6d33696ef e439b951 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in hci_sock_setsockopt
* Struck through repros no longer work on HEAD.