syzbot
KASAN: slab-out-of-bounds Read in reg_fixed_voltage_probe
Status:
premoderation: reported C repro on 2026/08/17 09:08
Reported-by: syzbot+a908d1543c126930ce42@syzkaller.appspotmail.com
First crash: 5d05h, last: 5d04h
Sample crash report:
BUG: KASAN: slab-out-of-bounds in reg_fixed_voltage_probe+0xb62/0xd90 drivers/regulator/fixed.c:279
Read of size 4 at addr ffff88810b2fee14 by task syz-executor266/312
CPU: 0 UID: 0 PID: 312 Comm: syz-executor266 Not tainted syzkaller #0 119f1c0cd44458c2ddc7f806e6d4d2dd11ae7dae
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:94
dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
print_address_description+0x71/0x210 mm/kasan/report.c:377
print_report+0x4a/0x70 mm/kasan/report.c:481
kasan_report+0x162/0x1a0 mm/kasan/report.c:594
__asan_report_load4_noabort+0x18/0x20 mm/kasan/report_generic.c:380
reg_fixed_voltage_probe+0xb62/0xd90 drivers/regulator/fixed.c:279
platform_probe+0x17a/0x200 drivers/base/platform.c:1404
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x2e1/0x8b0 drivers/base/dd.c:657
__driver_probe_device+0x193/0x280 drivers/base/dd.c:799
device_driver_attach+0xdb/0x1f0 drivers/base/dd.c:1126
bind_store+0x1dc/0x230 drivers/base/bus.c:267
drv_attr_store+0x91/0xb0 drivers/base/bus.c:125
sysfs_kf_write+0x13e/0x160 fs/sysfs/file.c:136
kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352
new_sync_write fs/read_write.c:591 [inline]
vfs_write+0x75f/0xfd0 fs/read_write.c:684
ksys_write+0x145/0x260 fs/read_write.c:737
__do_sys_write fs/read_write.c:749 [inline]
__se_sys_write fs/read_write.c:746 [inline]
__x64_sys_write+0x7f/0x90 fs/read_write.c:746
x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f4d3df56db9
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:00007ffe26533c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000200000000000 RCX: 00007f4d3df56db9
RDX: 000000000000000b RSI: 0000200000000700 RDI: 0000000000000005
RBP: 0000000000000001 R08: 00007ffe26533da8 R09: 00007ffe26533da8
R10: 00007ffe26533da8 R11: 0000000000000246 R12: 00007ffe26533d98
R13: 0000000000000002 R14: 00007f4d3dfe7ca0 R15: 0000200000000004
</TASK>
Allocated by task 1:
kasan_save_stack mm/kasan/common.c:49 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:70
kasan_save_alloc_info+0x3a/0x50 mm/kasan/generic.c:565
poison_kmalloc_redzone mm/kasan/common.c:379 [inline]
__kasan_kmalloc+0x96/0xb0 mm/kasan/common.c:396
kasan_kmalloc include/linux/kasan.h:261 [inline]
__do_kmalloc_node mm/slub.c:4395 [inline]
__kmalloc_node_track_caller_noprof+0x24e/0x4f0 mm/slub.c:4414
kmemdup_noprof+0x31/0x80 mm/util.c:139
kmemdup_noprof include/linux/fortify-string.h:753 [inline]
platform_device_add_data+0x49/0x130 drivers/base/platform.c:639
dummy_hcd_init+0x779/0x1230 drivers/usb/gadget/udc/dummy_hcd.c:2841
do_one_initcall+0x1e8/0x6a0 init/main.c:1406
do_initcall_level+0x174/0x2e5 init/main.c:1468
do_initcalls+0x7e/0x160 init/main.c:1484
do_basic_setup+0x95/0xb0 init/main.c:1503
kernel_init_freeable+0x2b1/0x400 init/main.c:1717
kernel_init+0x21/0x1e0 init/main.c:1606
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
The buggy address belongs to the object at ffff88810b2fee00
which belongs to the cache kmalloc-8 of size 8
The buggy address is located 12 bytes to the right of
allocated 8-byte region [ffff88810b2fee00, ffff88810b2fee08)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88810b2fea20 pfn:0x10b2fe
flags: 0x4000000000000200(workingset|zone=1)
page_type: f5(slab)
raw: 4000000000000200 ffff888100041500 ffffea000429b290 ffffea000416a410
raw: ffff88810b2fea20 0000000000800076 00000001f5000000 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 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 2447187214, free_ts 0
set_page_owner include/linux/page_owner.h:35 [inline]
post_alloc_hook+0x37d/0x3b0 mm/page_alloc.c:1863
prep_new_page+0x2d/0x180 mm/page_alloc.c:1871
get_page_from_freelist+0x4aea/0x4ba0 mm/page_alloc.c:3948
__alloc_pages_noprof+0x35a/0x7e0 mm/page_alloc.c:5315
alloc_slab_page+0x6b/0x1e0 mm/slub.c:-1
allocate_slab+0x69/0x430 mm/slub.c:2687
new_slab mm/slub.c:2741 [inline]
___slab_alloc+0x591/0x8c0 mm/slub.c:3934
__slab_alloc mm/slub.c:4025 [inline]
__slab_alloc_node mm/slub.c:4078 [inline]
slab_alloc_node mm/slub.c:4239 [inline]
__do_kmalloc_node mm/slub.c:4394 [inline]
__kmalloc_node_track_caller_noprof+0x2e3/0x4f0 mm/slub.c:4414
kstrdup+0x4d/0x130 mm/util.c:70
kstrdup_const+0x45/0x60 mm/util.c:93
__kernfs_new_node+0xaa/0x740 fs/kernfs/dir.c:624
kernfs_new_node+0x154/0x280 fs/kernfs/dir.c:704
kernfs_create_dir_ns+0x4b/0x130 fs/kernfs/dir.c:1065
sysfs_create_dir_ns+0x127/0x210 fs/sysfs/dir.c:59
create_dir lib/kobject.c:73 [inline]
kobject_add_internal+0x71f/0xc20 lib/kobject.c:240
kobject_add_varg lib/kobject.c:374 [inline]
kobject_add+0x169/0x240 lib/kobject.c:426
page_owner free stack trace missing
Memory state around the buggy address:
ffff88810b2fed00: 03 fc fc fc 00 fc fc fc 05 fc fc fc 00 fc fc fc
ffff88810b2fed80: 00 fc fc fc 00 fc fc fc 00 fc fc fc 00 fc fc fc
>ffff88810b2fee00: 00 fc fc fc fa fc fc fc 05 fc fc fc 00 fc fc fc
^
ffff88810b2fee80: 00 fc fc fc 00 fc fc fc 05 fc fc fc fa fc fc fc
ffff88810b2fef00: 00 fc fc fc 03 fc fc fc 00 fc fc fc 00 fc fc fc
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfa532f0ead581e8e: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: maybe wild-memory-access in range [0xd29998756ac0f470-0xd29998756ac0f477]
CPU: 0 UID: 0 PID: 312 Comm: syz-executor266 Tainted: G B syzkaller #0 119f1c0cd44458c2ddc7f806e6d4d2dd11ae7dae
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:regulator_register+0x929/0x19e0 drivers/regulator/core.c:5756
Code: a0 04 00 00 48 c7 c6 c0 aa 55 81 ba 00 00 20 00 31 c9 45 31 c0 e8 d7 ee 5c fe 4c 8b 7d b8 4d 85 ff 74 24 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 09 cd c6 fe 4d 8b 3f 4d 85 ff 74 0e
RSP: 0018:ffffc900011ef858 EFLAGS: 00010a06
RAX: 1a53330ead581e8e RBX: dffffc0000000000 RCX: ffff888106b59300
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900011ef900 R08: 0000000000000000 R09: 0000000000000000
R10: ffff88810b25e080 R11: ffffed102164bc12 R12: ffffc900011ef900
R13: ffff88810b25e0e8 R14: ffff88810b25e000 R15: d29998756ac0f473
FS: 0000555575f653c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557904152390 CR3: 0000000105b28000 CR4: 00000000003526b0
Call Trace:
<TASK>
devm_regulator_register+0x55/0xc0 drivers/regulator/devres.c:477
reg_fixed_voltage_probe+0x8f1/0xd90 drivers/regulator/fixed.c:331
platform_probe+0x17a/0x200 drivers/base/platform.c:1404
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x2e1/0x8b0 drivers/base/dd.c:657
__driver_probe_device+0x193/0x280 drivers/base/dd.c:799
device_driver_attach+0xdb/0x1f0 drivers/base/dd.c:1126
bind_store+0x1dc/0x230 drivers/base/bus.c:267
drv_attr_store+0x91/0xb0 drivers/base/bus.c:125
sysfs_kf_write+0x13e/0x160 fs/sysfs/file.c:136
kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352
new_sync_write fs/read_write.c:591 [inline]
vfs_write+0x75f/0xfd0 fs/read_write.c:684
ksys_write+0x145/0x260 fs/read_write.c:737
__do_sys_write fs/read_write.c:749 [inline]
__se_sys_write fs/read_write.c:746 [inline]
__x64_sys_write+0x7f/0x90 fs/read_write.c:746
x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f4d3df56db9
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:00007ffe26533c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000200000000000 RCX: 00007f4d3df56db9
RDX: 000000000000000b RSI: 0000200000000700 RDI: 0000000000000005
RBP: 0000000000000001 R08: 00007ffe26533da8 R09: 00007ffe26533da8
R10: 00007ffe26533da8 R11: 0000000000000246 R12: 00007ffe26533d98
R13: 0000000000000002 R14: 00007f4d3dfe7ca0 R15: 0000200000000004
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:regulator_register+0x929/0x19e0 drivers/regulator/core.c:5756
Code: a0 04 00 00 48 c7 c6 c0 aa 55 81 ba 00 00 20 00 31 c9 45 31 c0 e8 d7 ee 5c fe 4c 8b 7d b8 4d 85 ff 74 24 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 09 cd c6 fe 4d 8b 3f 4d 85 ff 74 0e
RSP: 0018:ffffc900011ef858 EFLAGS: 00010a06
RAX: 1a53330ead581e8e RBX: dffffc0000000000 RCX: ffff888106b59300
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900011ef900 R08: 0000000000000000 R09: 0000000000000000
R10: ffff88810b25e080 R11: ffffed102164bc12 R12: ffffc900011ef900
R13: ffff88810b25e0e8 R14: ffff88810b25e000 R15: d29998756ac0f473
FS: 0000555575f653c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005579043d6d78 CR3: 0000000105b28000 CR4: 00000000003526b0
----------------
Code disassembly (best guess):
0: a0 04 00 00 48 c7 c6 movabs 0xaac0c6c748000004,%al
7: c0 aa
9: 55 push %rbp
a: 81 ba 00 00 20 00 31 cmpl $0x3145c931,0x200000(%rdx)
11: c9 45 31
14: c0 e8 d7 shr $0xd7,%al
17: ee out %al,(%dx)
18: 5c pop %rsp
19: fe 4c 8b 7d decb 0x7d(%rbx,%rcx,4)
1d: b8 4d 85 ff 74 mov $0x74ff854d,%eax
22: 24 4c and $0x4c,%al
24: 89 f8 mov %edi,%eax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) <-- trapping instruction
2e: 74 08 je 0x38
30: 4c 89 ff mov %r15,%rdi
33: e8 09 cd c6 fe call 0xfec6cd41
38: 4d 8b 3f mov (%r15),%r15
3b: 4d 85 ff test %r15,%r15
3e: 74 0e je 0x4e
Struck through repros no longer work on HEAD.