Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Write in sco_sock_timeout
==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: slab-use-after-free in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline]
BUG: KASAN: slab-use-after-free in __refcount_add include/linux/refcount.h:184 [inline]
BUG: KASAN: slab-use-after-free in __refcount_inc include/linux/refcount.h:241 [inline]
BUG: KASAN: slab-use-after-free in refcount_inc include/linux/refcount.h:258 [inline]
BUG: KASAN: slab-use-after-free in sock_hold include/net/sock.h:781 [inline]
BUG: KASAN: slab-use-after-free in sco_sock_timeout+0x8b/0x270 net/bluetooth/sco.c:92
Write of size 4 at addr ffff88802639a080 by task kworker/1:2/1808
CPU: 1 UID: 0 PID: 1808 Comm: kworker/1:2 Not tainted 6.12.0-rc1-syzkaller-00113-g8c245fe7dde3-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events sco_sock_timeout
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline]
__refcount_add include/linux/refcount.h:184 [inline]
__refcount_inc include/linux/refcount.h:241 [inline]
refcount_inc include/linux/refcount.h:258 [inline]
sock_hold include/net/sock.h:781 [inline]
sco_sock_timeout+0x8b/0x270 net/bluetooth/sco.c:92
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 25:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:257 [inline]
__do_kmalloc_node mm/slub.c:4265 [inline]
__kmalloc_node_track_caller_noprof+0x225/0x440 mm/slub.c:4284
kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609
__alloc_skb+0x1f3/0x440 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x254/0xaa0 drivers/net/netdevsim/dev.c:850
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 25:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2343 [inline]
slab_free mm/slub.c:4580 [inline]
kfree+0x1a0/0x440 mm/slub.c:4728
skb_kfree_head net/core/skbuff.c:1086 [inline]
skb_free_head net/core/skbuff.c:1098 [inline]
skb_release_data+0x6a0/0x8a0 net/core/skbuff.c:1125
skb_release_all net/core/skbuff.c:1190 [inline]
__kfree_skb net/core/skbuff.c:1204 [inline]
consume_skb+0x9f/0xf0 net/core/skbuff.c:1436
nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
nsim_dev_trap_report_work+0x765/0xaa0 drivers/net/netdevsim/dev.c:850
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/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 ffff88802639a000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 128 bytes inside of
freed 4096-byte region [ffff88802639a000, ffff88802639b000)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26398
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888015442140 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff888015442140 dead000000000122 0000000000000000
head: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea000098e601 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5398, tgid 5398 (udevd), ts 123333990998, free_ts 123322335448
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
prep_new_page mm/page_alloc.c:1545 [inline]
get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457
__alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733
alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
alloc_slab_page+0x6a/0x120 mm/slub.c:2413
allocate_slab+0x5a/0x2f0 mm/slub.c:2579
new_slab mm/slub.c:2632 [inline]
___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819
__slab_alloc+0x58/0xa0 mm/slub.c:3909
__slab_alloc_node mm/slub.c:3962 [inline]
slab_alloc_node mm/slub.c:4123 [inline]
__do_kmalloc_node mm/slub.c:4264 [inline]
__kmalloc_noprof+0x25a/0x400 mm/slub.c:4277
kmalloc_noprof include/linux/slab.h:882 [inline]
tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path2_perm+0x3eb/0xbb0 security/tomoyo/file.c:923
tomoyo_path_rename+0x198/0x1e0 security/tomoyo/hooks.h:274
security_path_rename+0x266/0x4e0 security/security.c:2020
do_renameat2+0x94a/0x13f0 fs/namei.c:5157
__do_sys_rename fs/namei.c:5217 [inline]
__se_sys_rename fs/namei.c:5215 [inline]
__x64_sys_rename+0x82/0x90 fs/namei.c:5215
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
page last free pid 4548 tgid 4548 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1108 [inline]
free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638
__slab_free+0x31b/0x3d0 mm/slub.c:4491
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:247 [inline]
slab_post_alloc_hook mm/slub.c:4086 [inline]
slab_alloc_node mm/slub.c:4135 [inline]
__do_kmalloc_node mm/slub.c:4264 [inline]
__kmalloc_noprof+0x1a6/0x400 mm/slub.c:4277
kmalloc_noprof include/linux/slab.h:882 [inline]
tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
security_inode_getattr+0x130/0x330 security/security.c:2371
vfs_getattr+0x45/0x430 fs/stat.c:204
vfs_fstat fs/stat.c:229 [inline]
vfs_fstatat+0xe4/0x190 fs/stat.c:338
__do_sys_newfstatat fs/stat.c:505 [inline]
__se_sys_newfstatat fs/stat.c:499 [inline]
__x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:499
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff888026399f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802639a000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802639a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88802639a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802639a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Tested on:
commit: 8c245fe7 Merge tag 'net-6.12-rc2' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13156307980000
kernel config: https://syzkaller.appspot.com/x/.config?x=d0ca089c3fc6b54e
dashboard link: https://syzkaller.appspot.com/bug?extid=4c0d0c4cde787116d465
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=17377580580000
