==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff88807d448800 by task syz.4.1613/12392
CPU: 1 UID: 0 PID: 12392 Comm: syz.4.1613 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
vscnprintf lib/vsprintf.c:3018 [inline]
scnprintf+0xdb/0x150 lib/vsprintf.c:3071
f_midi2_opts_str_show drivers/usb/gadget/function/f_midi2.c:2187 [inline]
f_midi2_opts_iface_name_show+0x6e/0xa0 drivers/usb/gadget/function/f_midi2.c:2592
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x426/0x6f0 fs/configfs/file.c:88
__kernel_read+0x397/0xad0 fs/read_write.c:532
integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685
security_file_post_open+0xc4/0x210 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x5cd/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_open fs/open.c:1431 [inline]
__se_sys_open fs/open.c:1427 [inline]
__x64_sys_open+0xfe/0x1d0 fs/open.c:1427
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18419e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc1850e2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc184425fa0 RCX: 00007fc18419e0d9
RDX: 0000000000000041 RSI: 0000000000040280 RDI: 00002000000003c0
RBP: 00007fc184235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc184426038 R14: 00007fc184425fa0 R15: 00007ffd3236de18
Allocated by task 12345:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5337 [inline]
__kmalloc_node_track_caller_noprof+0x333/0x830 mm/slub.c:5466
__kmemdup_nul mm/util.c:64 [inline]
kstrndup+0x64/0x120 mm/util.c:120
f_midi2_opts_str_store.constprop.0+0xbf/0x240 drivers/usb/gadget/function/f_midi2.c:2205
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 12396:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2678 [inline]
slab_free mm/slub.c:6372 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6687
f_midi2_opts_str_store.constprop.0+0xf0/0x240 drivers/usb/gadget/function/f_midi2.c:2211
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807d448800
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
freed 32-byte region [ffff88807d448800, ffff88807d448820)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d448740 pfn:0x7d448
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801c028780 ffffea0000cb0f10 ffffea0000a42e90
raw: ffff88807d448740 0000000800400026 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5402, tgid 5402 (dhcpcd-run-hook), ts 64655838135
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3267 [inline]
allocate_slab mm/slub.c:3382 [inline]
new_slab+0xa5/0x640 mm/slub.c:3428
refill_objects+0xe3/0x410 mm/slub.c:7305
refill_sheaf mm/slub.c:2805 [inline]
__pcs_replace_empty_main+0x372/0x680 mm/slub.c:4677
alloc_from_pcs mm/slub.c:4775 [inline]
slab_alloc_node mm/slub.c:4907 [inline]
__kmalloc_cache_noprof+0x47b/0x6b0 mm/slub.c:5480
_kmalloc_noprof include/linux/slab.h:988 [inline]
slab_free_hook mm/slub.c:2630 [inline]
slab_free mm/slub.c:6372 [inline]
kmem_cache_free+0x40f/0x6b0 mm/slub.c:6499
tear_down_vmas+0x2a5/0x610 mm/mmap.c:1277
exit_mmap+0x469/0xa00 mm/mmap.c:1335
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
page last free pid 5402 tgid 5402 ts 64654489274 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
tlb_batch_list_free mm/mmu_gather.c:161 [inline]
tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552
exit_mmap+0x454/0xa00 mm/mmap.c:1328
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807d448700: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448780: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88807d448800: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
^
ffff88807d448880: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448900: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff88807d448801 by task syz.4.1613/12392
CPU: 1 UID: 0 PID: 12392 Comm: syz.4.1613 Tainted: G B L syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
vscnprintf lib/vsprintf.c:3018 [inline]
scnprintf+0xdb/0x150 lib/vsprintf.c:3071
f_midi2_opts_str_show drivers/usb/gadget/function/f_midi2.c:2187 [inline]
f_midi2_opts_iface_name_show+0x6e/0xa0 drivers/usb/gadget/function/f_midi2.c:2592
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x426/0x6f0 fs/configfs/file.c:88
__kernel_read+0x397/0xad0 fs/read_write.c:532
integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685
security_file_post_open+0xc4/0x210 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x5cd/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_open fs/open.c:1431 [inline]
__se_sys_open fs/open.c:1427 [inline]
__x64_sys_open+0xfe/0x1d0 fs/open.c:1427
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18419e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc1850e2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc184425fa0 RCX: 00007fc18419e0d9
RDX: 0000000000000041 RSI: 0000000000040280 RDI: 00002000000003c0
RBP: 00007fc184235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc184426038 R14: 00007fc184425fa0 R15: 00007ffd3236de18
Allocated by task 12345:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5337 [inline]
__kmalloc_node_track_caller_noprof+0x333/0x830 mm/slub.c:5466
__kmemdup_nul mm/util.c:64 [inline]
kstrndup+0x64/0x120 mm/util.c:120
f_midi2_opts_str_store.constprop.0+0xbf/0x240 drivers/usb/gadget/function/f_midi2.c:2205
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 12396:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2678 [inline]
slab_free mm/slub.c:6372 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6687
f_midi2_opts_str_store.constprop.0+0xf0/0x240 drivers/usb/gadget/function/f_midi2.c:2211
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807d448800
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 1 bytes inside of
freed 32-byte region [ffff88807d448800, ffff88807d448820)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d448740 pfn:0x7d448
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801c028780 ffffea0000cb0f10 ffffea0000a42e90
raw: ffff88807d448740 0000000800400026 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5402, tgid 5402 (dhcpcd-run-hook), ts 64655838135
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3267 [inline]
allocate_slab mm/slub.c:3382 [inline]
new_slab+0xa5/0x640 mm/slub.c:3428
refill_objects+0xe3/0x410 mm/slub.c:7305
refill_sheaf mm/slub.c:2805 [inline]
__pcs_replace_empty_main+0x372/0x680 mm/slub.c:4677
alloc_from_pcs mm/slub.c:4775 [inline]
slab_alloc_node mm/slub.c:4907 [inline]
__kmalloc_cache_noprof+0x47b/0x6b0 mm/slub.c:5480
_kmalloc_noprof include/linux/slab.h:988 [inline]
slab_free_hook mm/slub.c:2630 [inline]
slab_free mm/slub.c:6372 [inline]
kmem_cache_free+0x40f/0x6b0 mm/slub.c:6499
tear_down_vmas+0x2a5/0x610 mm/mmap.c:1277
exit_mmap+0x469/0xa00 mm/mmap.c:1335
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
page last free pid 5402 tgid 5402 ts 64654489274 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
tlb_batch_list_free mm/mmu_gather.c:161 [inline]
tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552
exit_mmap+0x454/0xa00 mm/mmap.c:1328
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807d448700: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448780: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88807d448800: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
^
ffff88807d448880: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448900: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff88807d448802 by task syz.4.1613/12392
CPU: 1 UID: 0 PID: 12392 Comm: syz.4.1613 Tainted: G B L syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
vscnprintf lib/vsprintf.c:3018 [inline]
scnprintf+0xdb/0x150 lib/vsprintf.c:3071
f_midi2_opts_str_show drivers/usb/gadget/function/f_midi2.c:2187 [inline]
f_midi2_opts_iface_name_show+0x6e/0xa0 drivers/usb/gadget/function/f_midi2.c:2592
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x426/0x6f0 fs/configfs/file.c:88
__kernel_read+0x397/0xad0 fs/read_write.c:532
integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685
security_file_post_open+0xc4/0x210 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x5cd/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_open fs/open.c:1431 [inline]
__se_sys_open fs/open.c:1427 [inline]
__x64_sys_open+0xfe/0x1d0 fs/open.c:1427
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18419e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc1850e2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc184425fa0 RCX: 00007fc18419e0d9
RDX: 0000000000000041 RSI: 0000000000040280 RDI: 00002000000003c0
RBP: 00007fc184235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc184426038 R14: 00007fc184425fa0 R15: 00007ffd3236de18
Allocated by task 12345:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5337 [inline]
__kmalloc_node_track_caller_noprof+0x333/0x830 mm/slub.c:5466
__kmemdup_nul mm/util.c:64 [inline]
kstrndup+0x64/0x120 mm/util.c:120
f_midi2_opts_str_store.constprop.0+0xbf/0x240 drivers/usb/gadget/function/f_midi2.c:2205
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 12396:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2678 [inline]
slab_free mm/slub.c:6372 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6687
f_midi2_opts_str_store.constprop.0+0xf0/0x240 drivers/usb/gadget/function/f_midi2.c:2211
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807d448800
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 2 bytes inside of
freed 32-byte region [ffff88807d448800, ffff88807d448820)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d448740 pfn:0x7d448
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801c028780 ffffea0000cb0f10 ffffea0000a42e90
raw: ffff88807d448740 0000000800400026 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5402, tgid 5402 (dhcpcd-run-hook), ts 64655838135
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3267 [inline]
allocate_slab mm/slub.c:3382 [inline]
new_slab+0xa5/0x640 mm/slub.c:3428
refill_objects+0xe3/0x410 mm/slub.c:7305
refill_sheaf mm/slub.c:2805 [inline]
__pcs_replace_empty_main+0x372/0x680 mm/slub.c:4677
alloc_from_pcs mm/slub.c:4775 [inline]
slab_alloc_node mm/slub.c:4907 [inline]
__kmalloc_cache_noprof+0x47b/0x6b0 mm/slub.c:5480
_kmalloc_noprof include/linux/slab.h:988 [inline]
slab_free_hook mm/slub.c:2630 [inline]
slab_free mm/slub.c:6372 [inline]
kmem_cache_free+0x40f/0x6b0 mm/slub.c:6499
tear_down_vmas+0x2a5/0x610 mm/mmap.c:1277
exit_mmap+0x469/0xa00 mm/mmap.c:1335
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
page last free pid 5402 tgid 5402 ts 64654489274 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
tlb_batch_list_free mm/mmu_gather.c:161 [inline]
tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552
exit_mmap+0x454/0xa00 mm/mmap.c:1328
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807d448700: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448780: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88807d448800: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
^
ffff88807d448880: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448900: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff88807d448803 by task syz.4.1613/12392
CPU: 1 UID: 0 PID: 12392 Comm: syz.4.1613 Tainted: G B L syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
vscnprintf lib/vsprintf.c:3018 [inline]
scnprintf+0xdb/0x150 lib/vsprintf.c:3071
f_midi2_opts_str_show drivers/usb/gadget/function/f_midi2.c:2187 [inline]
f_midi2_opts_iface_name_show+0x6e/0xa0 drivers/usb/gadget/function/f_midi2.c:2592
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x426/0x6f0 fs/configfs/file.c:88
__kernel_read+0x397/0xad0 fs/read_write.c:532
integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685
security_file_post_open+0xc4/0x210 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x5cd/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_open fs/open.c:1431 [inline]
__se_sys_open fs/open.c:1427 [inline]
__x64_sys_open+0xfe/0x1d0 fs/open.c:1427
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18419e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc1850e2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc184425fa0 RCX: 00007fc18419e0d9
RDX: 0000000000000041 RSI: 0000000000040280 RDI: 00002000000003c0
RBP: 00007fc184235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc184426038 R14: 00007fc184425fa0 R15: 00007ffd3236de18
Allocated by task 12345:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5337 [inline]
__kmalloc_node_track_caller_noprof+0x333/0x830 mm/slub.c:5466
__kmemdup_nul mm/util.c:64 [inline]
kstrndup+0x64/0x120 mm/util.c:120
f_midi2_opts_str_store.constprop.0+0xbf/0x240 drivers/usb/gadget/function/f_midi2.c:2205
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 12396:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2678 [inline]
slab_free mm/slub.c:6372 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6687
f_midi2_opts_str_store.constprop.0+0xf0/0x240 drivers/usb/gadget/function/f_midi2.c:2211
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807d448800
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 3 bytes inside of
freed 32-byte region [ffff88807d448800, ffff88807d448820)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d448740 pfn:0x7d448
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801c028780 ffffea0000cb0f10 ffffea0000a42e90
raw: ffff88807d448740 0000000800400026 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5402, tgid 5402 (dhcpcd-run-hook), ts 64655838135
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3267 [inline]
allocate_slab mm/slub.c:3382 [inline]
new_slab+0xa5/0x640 mm/slub.c:3428
refill_objects+0xe3/0x410 mm/slub.c:7305
refill_sheaf mm/slub.c:2805 [inline]
__pcs_replace_empty_main+0x372/0x680 mm/slub.c:4677
alloc_from_pcs mm/slub.c:4775 [inline]
slab_alloc_node mm/slub.c:4907 [inline]
__kmalloc_cache_noprof+0x47b/0x6b0 mm/slub.c:5480
_kmalloc_noprof include/linux/slab.h:988 [inline]
slab_free_hook mm/slub.c:2630 [inline]
slab_free mm/slub.c:6372 [inline]
kmem_cache_free+0x40f/0x6b0 mm/slub.c:6499
tear_down_vmas+0x2a5/0x610 mm/mmap.c:1277
exit_mmap+0x469/0xa00 mm/mmap.c:1335
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
page last free pid 5402 tgid 5402 ts 64654489274 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
tlb_batch_list_free mm/mmu_gather.c:161 [inline]
tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552
exit_mmap+0x454/0xa00 mm/mmap.c:1328
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807d448700: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448780: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88807d448800: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
^
ffff88807d448880: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448900: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff88807d448804 by task syz.4.1613/12392
CPU: 1 UID: 0 PID: 12392 Comm: syz.4.1613 Tainted: G B L syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
vscnprintf lib/vsprintf.c:3018 [inline]
scnprintf+0xdb/0x150 lib/vsprintf.c:3071
f_midi2_opts_str_show drivers/usb/gadget/function/f_midi2.c:2187 [inline]
f_midi2_opts_iface_name_show+0x6e/0xa0 drivers/usb/gadget/function/f_midi2.c:2592
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x426/0x6f0 fs/configfs/file.c:88
__kernel_read+0x397/0xad0 fs/read_write.c:532
integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685
security_file_post_open+0xc4/0x210 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x5cd/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_open fs/open.c:1431 [inline]
__se_sys_open fs/open.c:1427 [inline]
__x64_sys_open+0xfe/0x1d0 fs/open.c:1427
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18419e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc1850e2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc184425fa0 RCX: 00007fc18419e0d9
RDX: 0000000000000041 RSI: 0000000000040280 RDI: 00002000000003c0
RBP: 00007fc184235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc184426038 R14: 00007fc184425fa0 R15: 00007ffd3236de18
Allocated by task 12345:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5337 [inline]
__kmalloc_node_track_caller_noprof+0x333/0x830 mm/slub.c:5466
__kmemdup_nul mm/util.c:64 [inline]
kstrndup+0x64/0x120 mm/util.c:120
f_midi2_opts_str_store.constprop.0+0xbf/0x240 drivers/usb/gadget/function/f_midi2.c:2205
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 12396:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2678 [inline]
slab_free mm/slub.c:6372 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6687
f_midi2_opts_str_store.constprop.0+0xf0/0x240 drivers/usb/gadget/function/f_midi2.c:2211
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807d448800
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 4 bytes inside of
freed 32-byte region [ffff88807d448800, ffff88807d448820)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d448740 pfn:0x7d448
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801c028780 ffffea0000cb0f10 ffffea0000a42e90
raw: ffff88807d448740 0000000800400026 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5402, tgid 5402 (dhcpcd-run-hook), ts 64655838135
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3267 [inline]
allocate_slab mm/slub.c:3382 [inline]
new_slab+0xa5/0x640 mm/slub.c:3428
refill_objects+0xe3/0x410 mm/slub.c:7305
refill_sheaf mm/slub.c:2805 [inline]
__pcs_replace_empty_main+0x372/0x680 mm/slub.c:4677
alloc_from_pcs mm/slub.c:4775 [inline]
slab_alloc_node mm/slub.c:4907 [inline]
__kmalloc_cache_noprof+0x47b/0x6b0 mm/slub.c:5480
_kmalloc_noprof include/linux/slab.h:988 [inline]
slab_free_hook mm/slub.c:2630 [inline]
slab_free mm/slub.c:6372 [inline]
kmem_cache_free+0x40f/0x6b0 mm/slub.c:6499
tear_down_vmas+0x2a5/0x610 mm/mmap.c:1277
exit_mmap+0x469/0xa00 mm/mmap.c:1335
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
page last free pid 5402 tgid 5402 ts 64654489274 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
tlb_batch_list_free mm/mmu_gather.c:161 [inline]
tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552
exit_mmap+0x454/0xa00 mm/mmap.c:1328
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807d448700: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448780: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88807d448800: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
^
ffff88807d448880: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448900: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff88807d448805 by task syz.4.1613/12392
CPU: 1 UID: 0 PID: 12392 Comm: syz.4.1613 Tainted: G B L syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
vscnprintf lib/vsprintf.c:3018 [inline]
scnprintf+0xdb/0x150 lib/vsprintf.c:3071
f_midi2_opts_str_show drivers/usb/gadget/function/f_midi2.c:2187 [inline]
f_midi2_opts_iface_name_show+0x6e/0xa0 drivers/usb/gadget/function/f_midi2.c:2592
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x426/0x6f0 fs/configfs/file.c:88
__kernel_read+0x397/0xad0 fs/read_write.c:532
integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685
security_file_post_open+0xc4/0x210 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x5cd/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_open fs/open.c:1431 [inline]
__se_sys_open fs/open.c:1427 [inline]
__x64_sys_open+0xfe/0x1d0 fs/open.c:1427
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18419e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc1850e2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc184425fa0 RCX: 00007fc18419e0d9
RDX: 0000000000000041 RSI: 0000000000040280 RDI: 00002000000003c0
RBP: 00007fc184235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc184426038 R14: 00007fc184425fa0 R15: 00007ffd3236de18
Allocated by task 12345:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5337 [inline]
__kmalloc_node_track_caller_noprof+0x333/0x830 mm/slub.c:5466
__kmemdup_nul mm/util.c:64 [inline]
kstrndup+0x64/0x120 mm/util.c:120
f_midi2_opts_str_store.constprop.0+0xbf/0x240 drivers/usb/gadget/function/f_midi2.c:2205
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 12396:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2678 [inline]
slab_free mm/slub.c:6372 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6687
f_midi2_opts_str_store.constprop.0+0xf0/0x240 drivers/usb/gadget/function/f_midi2.c:2211
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807d448800
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 5 bytes inside of
freed 32-byte region [ffff88807d448800, ffff88807d448820)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d448740 pfn:0x7d448
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801c028780 ffffea0000cb0f10 ffffea0000a42e90
raw: ffff88807d448740 0000000800400026 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5402, tgid 5402 (dhcpcd-run-hook), ts 64655838135
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3267 [inline]
allocate_slab mm/slub.c:3382 [inline]
new_slab+0xa5/0x640 mm/slub.c:3428
refill_objects+0xe3/0x410 mm/slub.c:7305
refill_sheaf mm/slub.c:2805 [inline]
__pcs_replace_empty_main+0x372/0x680 mm/slub.c:4677
alloc_from_pcs mm/slub.c:4775 [inline]
slab_alloc_node mm/slub.c:4907 [inline]
__kmalloc_cache_noprof+0x47b/0x6b0 mm/slub.c:5480
_kmalloc_noprof include/linux/slab.h:988 [inline]
slab_free_hook mm/slub.c:2630 [inline]
slab_free mm/slub.c:6372 [inline]
kmem_cache_free+0x40f/0x6b0 mm/slub.c:6499
tear_down_vmas+0x2a5/0x610 mm/mmap.c:1277
exit_mmap+0x469/0xa00 mm/mmap.c:1335
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
page last free pid 5402 tgid 5402 ts 64654489274 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
tlb_batch_list_free mm/mmu_gather.c:161 [inline]
tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552
exit_mmap+0x454/0xa00 mm/mmap.c:1328
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807d448700: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448780: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88807d448800: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
^
ffff88807d448880: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448900: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff88807d448806 by task syz.4.1613/12392
CPU: 1 UID: 0 PID: 12392 Comm: syz.4.1613 Tainted: G B L syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
vscnprintf lib/vsprintf.c:3018 [inline]
scnprintf+0xdb/0x150 lib/vsprintf.c:3071
f_midi2_opts_str_show drivers/usb/gadget/function/f_midi2.c:2187 [inline]
f_midi2_opts_iface_name_show+0x6e/0xa0 drivers/usb/gadget/function/f_midi2.c:2592
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x426/0x6f0 fs/configfs/file.c:88
__kernel_read+0x397/0xad0 fs/read_write.c:532
integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685
security_file_post_open+0xc4/0x210 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x5cd/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_open fs/open.c:1431 [inline]
__se_sys_open fs/open.c:1427 [inline]
__x64_sys_open+0xfe/0x1d0 fs/open.c:1427
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18419e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc1850e2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc184425fa0 RCX: 00007fc18419e0d9
RDX: 0000000000000041 RSI: 0000000000040280 RDI: 00002000000003c0
RBP: 00007fc184235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc184426038 R14: 00007fc184425fa0 R15: 00007ffd3236de18
Allocated by task 12345:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5337 [inline]
__kmalloc_node_track_caller_noprof+0x333/0x830 mm/slub.c:5466
__kmemdup_nul mm/util.c:64 [inline]
kstrndup+0x64/0x120 mm/util.c:120
f_midi2_opts_str_store.constprop.0+0xbf/0x240 drivers/usb/gadget/function/f_midi2.c:2205
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 12396:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2678 [inline]
slab_free mm/slub.c:6372 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6687
f_midi2_opts_str_store.constprop.0+0xf0/0x240 drivers/usb/gadget/function/f_midi2.c:2211
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807d448800
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 6 bytes inside of
freed 32-byte region [ffff88807d448800, ffff88807d448820)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d448740 pfn:0x7d448
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801c028780 ffffea0000cb0f10 ffffea0000a42e90
raw: ffff88807d448740 0000000800400026 00000000f5000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5402, tgid 5402 (dhcpcd-run-hook), ts 64655838135
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35b0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3267 [inline]
allocate_slab mm/slub.c:3382 [inline]
new_slab+0xa5/0x640 mm/slub.c:3428
refill_objects+0xe3/0x410 mm/slub.c:7305
refill_sheaf mm/slub.c:2805 [inline]
__pcs_replace_empty_main+0x372/0x680 mm/slub.c:4677
alloc_from_pcs mm/slub.c:4775 [inline]
slab_alloc_node mm/slub.c:4907 [inline]
__kmalloc_cache_noprof+0x47b/0x6b0 mm/slub.c:5480
_kmalloc_noprof include/linux/slab.h:988 [inline]
slab_free_hook mm/slub.c:2630 [inline]
slab_free mm/slub.c:6372 [inline]
kmem_cache_free+0x40f/0x6b0 mm/slub.c:6499
tear_down_vmas+0x2a5/0x610 mm/mmap.c:1277
exit_mmap+0x469/0xa00 mm/mmap.c:1335
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
page last free pid 5402 tgid 5402 ts 64654489274 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
tlb_batch_list_free mm/mmu_gather.c:161 [inline]
tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552
exit_mmap+0x454/0xa00 mm/mmap.c:1328
__mmput+0x12a/0x410 kernel/fork.c:1193
mmput+0x67/0x80 kernel/fork.c:1216
exit_mm kernel/exit.c:614 [inline]
do_exit+0x8b1/0x2ae0 kernel/exit.c:996
do_group_exit+0xd5/0x2a0 kernel/exit.c:1151
__do_sys_exit_group kernel/exit.c:1162 [inline]
__se_sys_exit_group kernel/exit.c:1160 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1160
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807d448700: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448780: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88807d448800: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
^
ffff88807d448880: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
ffff88807d448900: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff88807d448807 by task syz.4.1613/12392
CPU: 1 UID: 0 PID: 12392 Comm: syz.4.1613 Tainted: G B L syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2949
vscnprintf lib/vsprintf.c:3018 [inline]
scnprintf+0xdb/0x150 lib/vsprintf.c:3071
f_midi2_opts_str_show drivers/usb/gadget/function/f_midi2.c:2187 [inline]
f_midi2_opts_iface_name_show+0x6e/0xa0 drivers/usb/gadget/function/f_midi2.c:2592
fill_read_buffer fs/configfs/file.c:68 [inline]
configfs_read_iter+0x426/0x6f0 fs/configfs/file.c:88
__kernel_read+0x397/0xad0 fs/read_write.c:532
integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28
ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222
ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280
ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300
process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425
ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685
security_file_post_open+0xc4/0x210 security/security.c:2755
do_open fs/namei.c:4839 [inline]
path_openat+0x5cd/0x2440 fs/namei.c:5000
do_file_open+0x20e/0x430 fs/namei.c:5029
do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_open fs/open.c:1431 [inline]
__se_sys_open fs/open.c:1427 [inline]
__x64_sys_open+0xfe/0x1d0 fs/open.c:1427
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc18419e0d9