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BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:644 [inline]
BUG: KASAN: slab-use-after-free in string+0x218/0x2b0 lib/vsprintf.c:726
Read of size 1 at addr ffff888029f68600 by task udevd/15970

CPU: 0 PID: 15970 Comm: udevd Not tainted 6.4.0-rc2-syzkaller-00338-ge2065b8c1b01 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:351 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:462
 kasan_report+0x176/0x1b0 mm/kasan/report.c:572
 string_nocheck lib/vsprintf.c:644 [inline]
 string+0x218/0x2b0 lib/vsprintf.c:726
 vsnprintf+0x10fc/0x1d80 lib/vsprintf.c:2817
 add_uevent_var+0x1c4/0x440 lib/kobject_uevent.c:665
 dev_uevent+0x3ec/0x8f0 drivers/base/core.c:2575
 uevent_show+0x19a/0x310 drivers/base/core.c:2646
 dev_attr_show+0x54/0xc0 drivers/base/core.c:2349
 sysfs_kf_seq_show+0x331/0x4b0 fs/sysfs/file.c:59
 seq_read_iter+0x43e/0xd10 fs/seq_file.c:230
 call_read_iter include/linux/fs.h:1862 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x788/0xb00 fs/read_write.c:470
 ksys_read+0x1a0/0x2c0 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fdfd6916b6a
Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffca7423248 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000556b0edc2430 RCX: 00007fdfd6916b6a
RDX: 0000000000001000 RSI: 0000556b0edb3930 RDI: 0000000000000008
RBP: 0000556b0edc2430 R08: 0000000000000008 R09: 0000000008000000
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000003fff R14: 00007ffca7423728 R15: 000000000000000a
 </TASK>

Allocated by task 15945:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:559 [inline]
 raw_ioctl_init drivers/usb/gadget/legacy/raw_gadget.c:460 [inline]
 raw_ioctl+0x1aad/0x3cd0 drivers/usb/gadget/legacy/raw_gadget.c:1250
 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:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 15945:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:162 [inline]
 slab_free_hook mm/slub.c:1781 [inline]
 slab_free_freelist_hook mm/slub.c:1807 [inline]
 slab_free mm/slub.c:3786 [inline]
 __kmem_cache_free+0x264/0x3c0 mm/slub.c:3799
 dev_free drivers/usb/gadget/legacy/raw_gadget.c:210 [inline]
 kref_put+0xb5/0x7c0 include/linux/kref.h:65
 raw_release+0x138/0x1e0 drivers/usb/gadget/legacy/raw_gadget.c:424
 __fput+0x3b7/0x890 fs/file_table.c:321
 task_work_run+0x24a/0x300 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x68f/0x2290 kernel/exit.c:871
 do_group_exit+0x206/0x2c0 kernel/exit.c:1021
 get_signal+0x1701/0x17e0 kernel/signal.c:2874
 arch_do_signal_or_restart+0x91/0x670 arch/x86/kernel/signal.c:306
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff888029f68600
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 freed 32-byte region [ffff888029f68600, ffff888029f68620)

The buggy address belongs to the physical page:
page:ffffea0000a7da00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29f68
anon flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000200 ffff888012441500 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000400040 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 9731, tgid 9731 (udevd), ts 197036357976, free_ts 196993922673
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1731
 prep_new_page mm/page_alloc.c:1738 [inline]
 get_page_from_freelist+0x321c/0x33a0 mm/page_alloc.c:3502
 __alloc_pages+0x255/0x670 mm/page_alloc.c:4768
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 alloc_slab_page+0x59/0x160 mm/slub.c:1853
 allocate_slab mm/slub.c:1998 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2051
 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3192
 __slab_alloc mm/slub.c:3291 [inline]
 __slab_alloc_node mm/slub.c:3344 [inline]
 slab_alloc_node mm/slub.c:3441 [inline]
 __kmem_cache_alloc_node+0x1b8/0x290 mm/slub.c:3490
 __do_kmalloc_node mm/slab_common.c:965 [inline]
 __kmalloc_node+0xa7/0x230 mm/slab_common.c:973
 kmalloc_array_node include/linux/slab.h:657 [inline]
 kcalloc_node include/linux/slab.h:662 [inline]
 memcg_alloc_slab_cgroups+0x81/0x120 mm/memcontrol.c:2928
 account_slab mm/slab.h:597 [inline]
 allocate_slab mm/slub.c:2016 [inline]
 new_slab+0xc0/0x2f0 mm/slub.c:2051
 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3192
 __slab_alloc mm/slub.c:3291 [inline]
 __slab_alloc_node mm/slub.c:3344 [inline]
 slab_alloc_node mm/slub.c:3441 [inline]
 __kmem_cache_alloc_node+0x1b8/0x290 mm/slub.c:3490
 __do_kmalloc_node mm/slab_common.c:965 [inline]
 __kmalloc_node+0xa7/0x230 mm/slab_common.c:973
 kmalloc_node include/linux/slab.h:579 [inline]
 kvmalloc_node+0x72/0x180 mm/util.c:604
 kvmalloc include/linux/slab.h:697 [inline]
 seq_buf_alloc fs/seq_file.c:38 [inline]
 seq_read_iter+0x202/0xd10 fs/seq_file.c:210
 call_read_iter include/linux/fs.h:1862 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x788/0xb00 fs/read_write.c:470
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1302 [inline]
 free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2564
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2659
 qlist_free_all+0x22/0x60 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x14b/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x23/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:186 [inline]
 slab_post_alloc_hook+0x68/0x3a0 mm/slab.h:711
 slab_alloc_node mm/slub.c:3451 [inline]
 __kmem_cache_alloc_node+0x14c/0x290 mm/slub.c:3490
 __do_kmalloc_node mm/slab_common.c:965 [inline]
 __kmalloc+0xa8/0x230 mm/slab_common.c:979
 kmalloc include/linux/slab.h:563 [inline]
 inotify_handle_inode_event+0x1c8/0x530 fs/notify/inotify/inotify_fsnotify.c:96
 inotify_ignored_and_remove_idr+0x29/0x70 fs/notify/inotify/inotify_user.c:527
 __do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:817 [inline]
 __se_sys_inotify_rm_watch+0x164/0x230 fs/notify/inotify/inotify_user.c:794
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff888029f68500: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
 ffff888029f68580: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
>ffff888029f68600: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
                   ^
 ffff888029f68680: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
 ffff888029f68700: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc
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