================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:646 [inline] BUG: KASAN: slab-use-after-free in string+0x218/0x2b0 lib/vsprintf.c:728 Read of size 1 at addr ffff88807018bd40 by task udevd/4525 CPU: 1 PID: 4525 Comm: udevd Not tainted 6.8.0-rc7-syzkaller-00142-g3aaa8ce7a335 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x167/0x540 mm/kasan/report.c:488 kasan_report+0x142/0x180 mm/kasan/report.c:601 string_nocheck lib/vsprintf.c:646 [inline] string+0x218/0x2b0 lib/vsprintf.c:728 vsnprintf+0x1101/0x1da0 lib/vsprintf.c:2824 add_uevent_var+0x1c8/0x450 lib/kobject_uevent.c:665 dev_uevent+0x3ec/0x900 drivers/base/core.c:2590 uevent_show+0x1a1/0x310 drivers/base/core.c:2661 dev_attr_show+0x55/0xc0 drivers/base/core.c:2364 sysfs_kf_seq_show+0x334/0x4c0 fs/sysfs/file.c:59 seq_read_iter+0x445/0xd60 fs/seq_file.c:230 call_read_iter include/linux/fs.h:2081 [inline] new_sync_read fs/read_write.c:395 [inline] vfs_read+0x978/0xb70 fs/read_write.c:476 ksys_read+0x1a0/0x2c0 fs/read_write.c:619 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f243db16b6a 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:00007fff91e34b78 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00005650734608c0 RCX: 00007f243db16b6a RDX: 0000000000001000 RSI: 0000565073461ff0 RDI: 000000000000000c RBP: 00005650734608c0 R08: 000000000000000c R09: 0000000004000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007fff91e35058 R15: 000000000000000a Allocated by task 24851: 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:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace+0x1d6/0x360 mm/slub.c:4012 kmalloc include/linux/slab.h:590 [inline] raw_ioctl_init drivers/usb/gadget/legacy/raw_gadget.c:509 [inline] raw_ioctl+0x1aad/0x3ce0 drivers/usb/gadget/legacy/raw_gadget.c:1303 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:857 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 Freed by task 24850: 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:589 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kfree+0x14a/0x380 mm/slub.c:4409 dev_free drivers/usb/gadget/legacy/raw_gadget.c:211 [inline] kref_put+0xb5/0x7c0 include/linux/kref.h:65 raw_release+0x138/0x1e0 drivers/usb/gadget/legacy/raw_gadget.c:473 __fput+0x429/0x8a0 fs/file_table.c:376 __do_sys_close fs/open.c:1554 [inline] __se_sys_close fs/open.c:1539 [inline] __x64_sys_close+0x7e/0x110 fs/open.c:1539 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 The buggy address belongs to the object at ffff88807018bd40 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of freed 32-byte region [ffff88807018bd40, ffff88807018bd60) The buggy address belongs to the physical page: page:ffffea0001c062c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7018b anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888014c41500 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080400040 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 0x112c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 29643, tgid 29643 (syz-executor.0), ts 1037090607603, free_ts 1036889236552 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311 __alloc_pages+0x255/0x680 mm/page_alloc.c:4569 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2190 allocate_slab mm/slub.c:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xd17/0x13e0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] __do_kmalloc_node mm/slub.c:3980 [inline] __kmalloc+0x2e0/0x490 mm/slub.c:3994 kmalloc include/linux/slab.h:594 [inline] kzalloc include/linux/slab.h:711 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80 tomoyo_path_perm+0x3ca/0x740 security/tomoyo/file.c:831 tomoyo_path_symlink+0xde/0x120 security/tomoyo/tomoyo.c:212 security_path_symlink+0xe3/0x140 security/security.c:1871 do_symlinkat+0x136/0x3a0 fs/namei.c:4508 __do_sys_symlinkat fs/namei.c:4526 [inline] __se_sys_symlinkat fs/namei.c:4523 [inline] __x64_sys_symlinkat+0x99/0xb0 fs/namei.c:4523 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 page last free pid 8 tgid 8 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486 folio_put include/linux/mm.h:1494 [inline] put_page include/linux/mm.h:1563 [inline] aio_free_ring+0x27e/0x6c0 fs/aio.c:344 free_ioctx+0x22/0xa0 fs/aio.c:628 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 Memory state around the buggy address: ffff88807018bc00: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ffff88807018bc80: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc >ffff88807018bd00: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ^ ffff88807018bd80: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff88807018be00: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ==================================================================