================================================================== BUG: KASAN: use-after-free in strcmp+0x9b/0xb0 lib/string.c:346 Read of size 1 at addr ffff88801d11b1c0 by task syz-executor107/4003 CPU: 1 PID: 4003 Comm: syz-executor107 Not tainted 5.16.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x57/0x7d lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 strcmp+0x9b/0xb0 lib/string.c:346 replace_vma_anon_name mm/madvise.c:110 [inline] madvise_update_vma+0x40f/0x6a0 mm/madvise.c:181 madvise_vma_behavior+0xdb/0x1380 mm/madvise.c:1012 madvise_walk_vmas+0x164/0x280 mm/madvise.c:1176 do_madvise.part.0+0x119/0x270 mm/madvise.c:1354 do_madvise mm/madvise.c:1367 [inline] __do_sys_madvise mm/madvise.c:1367 [inline] __se_sys_madvise mm/madvise.c:1365 [inline] __x64_sys_madvise+0xcc/0x130 mm/madvise.c:1365 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f973ea84b19 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe99758f88 EFLAGS: 00000246 ORIG_RAX: 000000000000001c RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f973ea84b19 RDX: 000000000000000b RSI: 0000000000001000 RDI: 0000000020ffc000 RBP: 00007f973ea48cc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 00007f973ea48d50 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3614: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:590 [inline] kzalloc include/linux/slab.h:724 [inline] apparmor_sk_alloc_security+0x69/0xf0 security/apparmor/lsm.c:785 security_sk_alloc+0x44/0x80 security/security.c:2263 sk_prot_alloc+0x178/0x200 net/core/sock.c:1923 sk_alloc+0x27/0x810 net/core/sock.c:1973 inet_create net/ipv4/af_inet.c:318 [inline] inet_create+0x2a4/0xd60 net/ipv4/af_inet.c:244 __sock_create+0x23e/0x590 net/socket.c:1464 sock_create net/socket.c:1515 [inline] __sys_socket+0xd6/0x1a0 net/socket.c:1557 __do_sys_socket net/socket.c:1566 [inline] __se_sys_socket net/socket.c:1564 [inline] __x64_sys_socket+0x6a/0xb0 net/socket.c:1564 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 4003: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749 slab_free mm/slub.c:3513 [inline] kfree+0xf6/0x560 mm/slub.c:4561 free_vma_anon_name mm/madvise.c:96 [inline] free_vma_anon_name+0x59/0xa0 mm/madvise.c:91 vm_area_free+0x9/0x20 kernel/fork.c:375 __vma_adjust+0x738/0x20b0 mm/mmap.c:961 vma_merge+0x6f9/0x12e0 mm/mmap.c:1216 madvise_update_vma+0x199/0x6a0 mm/madvise.c:149 madvise_vma_behavior+0xdb/0x1380 mm/madvise.c:1012 madvise_walk_vmas+0x164/0x280 mm/madvise.c:1176 do_madvise.part.0+0x119/0x270 mm/madvise.c:1354 do_madvise mm/madvise.c:1367 [inline] __do_sys_madvise mm/madvise.c:1367 [inline] __se_sys_madvise mm/madvise.c:1365 [inline] __x64_sys_madvise+0xcc/0x130 mm/madvise.c:1365 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88801d11b1c0 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 0 bytes inside of 16-byte region [ffff88801d11b1c0, ffff88801d11b1d0) The buggy address belongs to the page: page:ffffea00007446c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d11b flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000001 ffff88800fc413c0 raw: 0000000000000000 0000000080800080 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 1, ts 4776970319, free_ts 0 prep_new_page mm/page_alloc.c:2428 [inline] get_page_from_freelist+0xa6f/0x2f10 mm/page_alloc.c:4159 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5379 alloc_page_interleave+0xf/0x1c0 mm/mempolicy.c:2037 alloc_slab_page mm/slub.c:1793 [inline] allocate_slab mm/slub.c:1930 [inline] new_slab+0x32d/0x4a0 mm/slub.c:1993 ___slab_alloc+0x91a/0xfd0 mm/slub.c:3022 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3109 slab_alloc_node mm/slub.c:3200 [inline] slab_alloc mm/slub.c:3242 [inline] __kmalloc_track_caller+0x2e7/0x320 mm/slub.c:4925 kstrdup+0x29/0x50 mm/util.c:60 __kernfs_new_node+0x94/0x7b0 fs/kernfs/dir.c:581 kernfs_new_node fs/kernfs/dir.c:647 [inline] kernfs_create_dir_ns+0x80/0x220 fs/kernfs/dir.c:984 sysfs_create_dir_ns+0x116/0x260 fs/sysfs/dir.c:59 create_dir lib/kobject.c:89 [inline] kobject_add_internal+0x27b/0x930 lib/kobject.c:255 kobject_add_varg lib/kobject.c:390 [inline] kobject_add+0x120/0x190 lib/kobject.c:442 device_add+0x2d6/0x1b80 drivers/base/core.c:3329 usb_hub_create_port_device+0x361/0xc90 drivers/usb/core/port.c:564 hub_configure drivers/usb/core/hub.c:1655 [inline] hub_probe.cold+0x1f9b/0x24a6 drivers/usb/core/hub.c:1889 page_owner free stack trace missing Memory state around the buggy address: ffff88801d11b080: 00 00 fc fc 00 00 fc fc 00 00 fc fc 00 00 fc fc ffff88801d11b100: 00 00 fc fc 00 00 fc fc 00 00 fc fc fa fb fc fc >ffff88801d11b180: fa fb fc fc 00 00 fc fc fa fb fc fc fb fb fc fc ^ ffff88801d11b200: fb fb fc fc fb fb fc fc fb fb fc fc fb fb fc fc ffff88801d11b280: fb fb fc fc fb fb fc fc fb fb fc fc 00 07 fc fc ==================================================================