================================================================== 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 ffff888023e6bac4 by task udevd/5112 CPU: 0 PID: 5112 Comm: udevd Not tainted 6.9.0-rc7-syzkaller-00023-g6d7ddd805123 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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 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:664 dev_uevent+0x3ec/0x900 drivers/base/core.c:2671 uevent_show+0x1a1/0x310 drivers/base/core.c:2742 dev_attr_show+0x55/0xc0 drivers/base/core.c:2445 sysfs_kf_seq_show+0x331/0x4c0 fs/sysfs/file.c:59 seq_read_iter+0x445/0xd60 fs/seq_file.c:230 call_read_iter include/linux/fs.h:2104 [inline] new_sync_read fs/read_write.c:395 [inline] vfs_read+0x97b/0xb70 fs/read_write.c:476 ksys_read+0x1a0/0x2c0 fs/read_write.c:619 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6fd2916b6a 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:00007ffc49d0bea8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000562a21d42590 RCX: 00007f6fd2916b6a RDX: 0000000000001000 RSI: 0000562a21d4a070 RDI: 0000000000000008 RBP: 0000562a21d42590 R08: 0000000000000008 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffc49d0c388 R15: 000000000000000a Allocated by task 13927: 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+0x1db/0x370 mm/slub.c:4003 kmalloc include/linux/slab.h:628 [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 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x51c/0xca0 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb8/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 13926: 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+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:2111 [inline] slab_free mm/slub.c:4286 [inline] kfree+0x153/0x3b0 mm/slub.c:4396 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:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb8/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff888023e6bac0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 4 bytes inside of freed 32-byte region [ffff888023e6bac0, ffff888023e6bae0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23e6b flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888015041500 dead000000000100 dead000000000122 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5114, tgid -59180339 (syz-executor.0), ts 5114, free_ts 55555941185 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 __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:2180 allocate_slab mm/slub.c:2343 [inline] new_slab+0x84/0x2f0 mm/slub.c:2396 ___slab_alloc+0xc73/0x1260 mm/slub.c:3530 __slab_alloc mm/slub.c:3615 [inline] __slab_alloc_node mm/slub.c:3668 [inline] slab_alloc_node mm/slub.c:3841 [inline] kmalloc_trace+0x269/0x370 mm/slub.c:3998 kmalloc include/linux/slab.h:628 [inline] kzalloc include/linux/slab.h:749 [inline] ref_tracker_alloc+0x14b/0x490 lib/ref_tracker.c:203 __netdev_tracker_alloc include/linux/netdevice.h:4064 [inline] netdev_hold include/linux/netdevice.h:4093 [inline] neigh_parms_alloc+0x221/0x570 net/core/neighbour.c:1723 ipv6_add_dev+0x2ee/0x1220 net/ipv6/addrconf.c:398 addrconf_notify+0x6a7/0x1020 net/ipv6/addrconf.c:3651 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:1988 [inline] call_netdevice_notifiers net/core/dev.c:2002 [inline] register_netdevice+0x15b2/0x1a20 net/core/dev.c:10316 register_netdev+0x3b/0x50 net/core/dev.c:10413 vti6_init_net+0x233/0x2f0 net/ipv6/ip6_vti.c:1163 ops_init+0x352/0x610 net/core/net_namespace.c:136 page last free pid 5109 tgid 5109 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1141 [inline] free_unref_page_prepare+0x986/0xab0 mm/page_alloc.c:2347 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487 __slab_free+0x31b/0x3d0 mm/slub.c:4198 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x5e/0xc0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3804 [inline] slab_alloc_node mm/slub.c:3851 [inline] kmem_cache_alloc+0x174/0x350 mm/slub.c:3858 kmem_cache_zalloc include/linux/slab.h:739 [inline] seq_open+0x62/0x140 fs/seq_file.c:63 kernfs_fop_open+0x635/0xd10 do_dentry_open+0x907/0x15a0 fs/open.c:955 do_open fs/namei.c:3642 [inline] path_openat+0x2860/0x3240 fs/namei.c:3799 do_filp_open+0x235/0x490 fs/namei.c:3826 do_sys_openat2+0x13e/0x1d0 fs/open.c:1406 do_sys_open fs/open.c:1421 [inline] __do_sys_openat fs/open.c:1437 [inline] __se_sys_openat fs/open.c:1432 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1432 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888023e6b980: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff888023e6ba00: 00 00 00 fc fc fc fc fc 00 00 00 00 fc fc fc fc >ffff888023e6ba80: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ^ ffff888023e6bb00: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc ffff888023e6bb80: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ==================================================================