================================================================== BUG: KASAN: use-after-free in get_disk_and_module block/genhd.c:1788 [inline] BUG: KASAN: use-after-free in exact_lock+0x38/0xc0 block/genhd.c:677 Read of size 8 at addr ffff88810e66e450 by task udevd/409 CPU: 1 PID: 409 Comm: udevd Not tainted 5.10.117-syzkaller-986967-g0974b8411a58-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118 print_address_description+0x81/0x3c0 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 get_disk_and_module block/genhd.c:1788 [inline] exact_lock+0x38/0xc0 block/genhd.c:677 kobj_lookup+0x2a7/0x440 drivers/base/map.c:119 get_gendisk+0xf6/0x3c0 block/genhd.c:1002 bdev_get_gendisk fs/block_dev.c:1108 [inline] __blkdev_get+0x1a4/0x1360 fs/block_dev.c:1472 blkdev_get fs/block_dev.c:1651 [inline] blkdev_open+0x21a/0x450 fs/block_dev.c:1768 do_dentry_open+0x7a2/0x1090 fs/open.c:819 vfs_open+0x73/0x80 fs/open.c:942 do_open fs/namei.c:3327 [inline] path_openat+0x2638/0x2fd0 fs/namei.c:3444 do_filp_open+0x200/0x440 fs/namei.c:3471 do_sys_openat2+0x13b/0x470 fs/open.c:1211 do_sys_open fs/open.c:1227 [inline] __do_sys_openat fs/open.c:1243 [inline] __se_sys_openat fs/open.c:1238 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1238 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f211039b697 Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f RSP: 002b:00007ffc15f88c10 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000056408f1df6a0 RCX: 00007f211039b697 RDX: 00000000000a0800 RSI: 000056408f1b7810 RDI: 00000000ffffff9c RBP: 000056408f1b7810 R08: 00000000ffffffff R09: 00007ffc15ff00b8 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800 R13: 000056408f1b9b00 R14: 0000000000000001 R15: 000056408f1ab2c0 Allocated by task 429: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:428 [inline] ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:507 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:516 kasan_kmalloc include/linux/kasan.h:269 [inline] kmem_cache_alloc_trace+0x1dd/0x330 mm/slub.c:2983 kmem_cache_alloc_node_trace include/linux/slab.h:440 [inline] kmalloc_node include/linux/slab.h:570 [inline] kzalloc_node include/linux/slab.h:675 [inline] __alloc_disk_node+0x75/0x330 block/genhd.c:1728 loop_add+0x36a/0x8a0 drivers/block/loop.c:2133 loop_control_ioctl+0x564/0x740 drivers/block/loop.c:2300 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0x115/0x190 fs/ioctl.c:739 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:739 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 429: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:357 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:360 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1604 [inline] slab_free_freelist_hook+0xcc/0x1a0 mm/slub.c:1630 slab_free mm/slub.c:3212 [inline] kfree+0xc3/0x290 mm/slub.c:4200 disk_release+0x240/0x2a0 block/genhd.c:1569 device_release+0x9c/0x1d0 drivers/base/core.c:2114 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x163/0x240 lib/kobject.c:753 put_disk+0x23/0x30 block/genhd.c:1816 loop_add+0x666/0x8a0 drivers/block/loop.c:2178 loop_control_ioctl+0x564/0x740 drivers/block/loop.c:2300 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0x115/0x190 fs/ioctl.c:739 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:739 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88810e66e000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1104 bytes inside of 2048-byte region [ffff88810e66e000, ffff88810e66e800) The buggy address belongs to the page: page:ffffea0004399a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10e668 head:ffffea0004399a00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff888100042d80 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 427, ts 41081903773, free_ts 40319206011 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2385 [inline] prep_new_page mm/page_alloc.c:2391 [inline] get_page_from_freelist+0x745/0x760 mm/page_alloc.c:4067 __alloc_pages_nodemask+0x3b6/0x890 mm/page_alloc.c:5117 alloc_slab_page mm/slub.c:1815 [inline] allocate_slab+0x78/0x540 mm/slub.c:1817 new_slab mm/slub.c:1878 [inline] new_slab_objects mm/slub.c:2637 [inline] ___slab_alloc+0x131/0x2e0 mm/slub.c:2800 __slab_alloc+0x63/0xa0 mm/slub.c:2840 slab_alloc_node mm/slub.c:2922 [inline] slab_alloc mm/slub.c:2964 [inline] kmem_cache_alloc_trace+0x20e/0x330 mm/slub.c:2981 kmem_cache_alloc_node_trace include/linux/slab.h:440 [inline] kmalloc_node include/linux/slab.h:570 [inline] kzalloc_node include/linux/slab.h:675 [inline] bdi_alloc+0x4e/0x110 mm/backing-dev.c:738 blk_alloc_queue+0x111/0x640 block/blk-core.c:543 blk_mq_init_queue_data block/blk-mq.c:3141 [inline] blk_mq_init_queue+0x35/0xc0 block/blk-mq.c:3160 loop_add+0x26e/0x8a0 drivers/block/loop.c:2115 loop_control_ioctl+0x564/0x740 drivers/block/loop.c:2300 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0x115/0x190 fs/ioctl.c:739 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:739 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1331 [inline] __free_pages_ok+0x7f8/0x830 mm/page_alloc.c:1611 free_the_page mm/page_alloc.c:5178 [inline] __free_pages+0x2d2/0x4c0 mm/page_alloc.c:5184 __free_slab+0xd3/0x190 mm/slub.c:1903 free_slab mm/slub.c:1918 [inline] discard_slab mm/slub.c:1924 [inline] unfreeze_partials+0x17d/0x1b0 mm/slub.c:2418 put_cpu_partial+0xc8/0x190 mm/slub.c:2454 __slab_free+0x2d8/0x3a0 mm/slub.c:3104 do_slab_free mm/slub.c:3200 [inline] ___cache_free+0x11f/0x140 mm/slub.c:3219 qlink_free+0x38/0x40 mm/kasan/quarantine.c:146 qlist_free_all+0x4c/0xc0 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x15a/0x170 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x2f/0xe0 mm/kasan/common.c:438 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:583 [inline] slab_alloc_node mm/slub.c:2956 [inline] slab_alloc mm/slub.c:2964 [inline] kmem_cache_alloc+0x16c/0x300 mm/slub.c:2969 kmem_cache_alloc_node include/linux/slab.h:423 [inline] __alloc_skb+0x7e/0x580 net/core/skbuff.c:199 alloc_skb include/linux/skbuff.h:1101 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1185 [inline] netlink_sendmsg+0x7a4/0xd00 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x597/0x8e0 net/socket.c:2343 ___sys_sendmsg net/socket.c:2397 [inline] __sys_sendmsg+0x37b/0x460 net/socket.c:2430 Memory state around the buggy address: ffff88810e66e300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88810e66e380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88810e66e400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88810e66e480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88810e66e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================