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agk@redhat.com, bmarzins@redhat.com, dm-devel@lists.linux.dev, linux-kernel@vger.kernel.org, mpatocka@redhat.com, snitzer@kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 330517c63aa9 Merge tag 'char-misc-7.4-rc1' of git://git.ke.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13608531580000 kernel config: https://syzkaller.appspot.com/x/.config?x=b03c85f3988bfcd5 dashboard link: https://syzkaller.appspot.com/bug?extid=9519233e6d144970bbc2 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11bd638e580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15bd638e580000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-330517c6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/ecb230491807/vmlinux-330517c6.xz kernel image: https://storage.googleapis.com/syzbot-assets/ace3132a7acc/bzImage-330517c6.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9519233e6d144970bbc2@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:650 [inline] BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:732 Read of size 1 at addr ffff888030bb3db4 by task syz.0.17/6012 CPU: 0 UID: 0 PID: 6012 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 string_nocheck lib/vsprintf.c:650 [inline] string+0x471/0x4d0 lib/vsprintf.c:732 vsnprintf+0x422/0x1300 lib/vsprintf.c:2948 vprintk_store+0x3b3/0xbe0 kernel/printk/printk.c:2307 vprintk_emit+0x139/0x6b0 kernel/printk/printk.c:2455 _printk+0xcf/0x110 kernel/printk/printk.c:2504 dm_put_device+0x2fa/0x3a0 drivers/md/dm-table.c:467 pool_ctr+0x3b8/0x2380 drivers/md/dm-thin.c:3431 dm_table_add_target+0x58b/0xee0 drivers/md/dm-table.c:749 populate_table drivers/md/dm-ioctl.c:1602 [inline] table_load+0x3b9/0x7b0 drivers/md/dm-ioctl.c:1645 ctl_ioctl+0x4d2/0xcc0 drivers/md/dm-ioctl.c:2221 dm_ctl_ioctl+0x22/0x30 drivers/md/dm-ioctl.c:2243 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcd6159f559 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffcc68ce338 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fcd61825fa0 RCX: 00007fcd6159f559 RDX: 00002000000004c0 RSI: 00000000c138fd09 RDI: 0000000000000003 RBP: 00007fcd61636b20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcd61825fac R14: 00007fcd61825fa0 R15: 00007fcd61825fa0 Allocated by task 6012: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:409 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:426 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_node_noprof+0x30c/0x710 mm/slub.c:5699 _kmalloc_node_noprof include/linux/slab.h:1196 [inline] open_table_device drivers/md/dm.c:733 [inline] dm_get_table_device+0x2fc/0x820 drivers/md/dm.c:821 dm_get_device+0x525/0x7e0 drivers/md/dm-table.c:388 pool_ctr+0x2a8/0x2380 drivers/md/dm-thin.c:3329 dm_table_add_target+0x58b/0xee0 drivers/md/dm-table.c:749 populate_table drivers/md/dm-ioctl.c:1602 [inline] table_load+0x3b9/0x7b0 drivers/md/dm-ioctl.c:1645 ctl_ioctl+0x4d2/0xcc0 drivers/md/dm-ioctl.c:2221 dm_ctl_ioctl+0x22/0x30 drivers/md/dm-ioctl.c:2243 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6012: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:264 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:296 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2780 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x22b/0x6d0 mm/slub.c:6923 close_table_device drivers/md/dm.c:798 [inline] dm_put_table_device+0x2bf/0x380 drivers/md/dm.c:841 upgrade_mode drivers/md/dm-table.c:326 [inline] dm_get_device+0x3f1/0x7e0 drivers/md/dm-table.c:399 pool_ctr+0x362/0x2380 drivers/md/dm-thin.c:3336 dm_table_add_target+0x58b/0xee0 drivers/md/dm-table.c:749 populate_table drivers/md/dm-ioctl.c:1602 [inline] table_load+0x3b9/0x7b0 drivers/md/dm-ioctl.c:1645 ctl_ioctl+0x4d2/0xcc0 drivers/md/dm-ioctl.c:2221 dm_ctl_ioctl+0x22/0x30 drivers/md/dm-ioctl.c:2243 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888030bb3d80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 52 bytes inside of freed 96-byte region [ffff888030bb3d80, ffff888030bb3de0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888030bb3c80 pfn:0x30bb3 flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000200 ffff88801d442280 ffffea00008fef50 ffffea0000ba1e50 raw: ffff888030bb3c80 0000000000200016 00000000f5000000 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 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 446, tgid 446 (kworker/u33:10), ts 8752841003 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1854 prep_new_page mm/page_alloc.c:1862 [inline] get_page_from_freelist+0x1113/0x35e0 mm/page_alloc.c:3933 __alloc_frozen_pages_noprof+0x2f6/0x3190 mm/page_alloc.c:5429 alloc_slab_page mm/slub.c:3384 [inline] allocate_slab mm/slub.c:3499 [inline] new_slab+0xb1/0x6d0 mm/slub.c:3550 refill_objects+0xe3/0x410 mm/slub.c:7539 refill_sheaf mm/slub.c:2917 [inline] __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4811 alloc_from_pcs mm/slub.c:4887 [inline] slab_alloc_node mm/slub.c:5021 [inline] __kmalloc_cache_node_noprof+0x517/0x710 mm/slub.c:5695 _kmalloc_node_noprof include/linux/slab.h:1196 [inline] __get_vm_area_node+0x124/0x350 mm/vmalloc.c:3237 __vmalloc_node_range_noprof+0x2ad/0x1440 mm/vmalloc.c:4079 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4180 alloc_thread_stack_node kernel/fork.c:359 [inline] dup_task_struct kernel/fork.c:930 [inline] copy_process+0x80b/0x84c0 kernel/fork.c:2141 kernel_clone+0x176/0x9d0 kernel/fork.c:2783 user_mode_thread+0xd1/0x120 kernel/fork.c:2860 call_usermodehelper_exec_work kernel/umh.c:169 [inline] call_usermodehelper_exec_work+0xcb/0x180 kernel/umh.c:155 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3495 process_scheduled_works kernel/workqueue.c:3578 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3659 page last free pid 446 tgid 446 ts 8752713246 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1401 [inline] __free_frozen_pages+0x7b4/0x1110 mm/page_alloc.c:2952 __kasan_populate_vmalloc_do mm/kasan/shadow.c:393 [inline] __kasan_populate_vmalloc+0x1ea/0x210 mm/kasan/shadow.c:424 kasan_populate_vmalloc include/linux/kasan.h:580 [inline] alloc_vmap_area+0x963/0x2bc0 mm/vmalloc.c:2145 __get_vm_area_node+0x1ed/0x350 mm/vmalloc.c:3248 __vmalloc_node_range_noprof+0x2ad/0x1440 mm/vmalloc.c:4079 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4180 alloc_thread_stack_node kernel/fork.c:359 [inline] dup_task_struct kernel/fork.c:930 [inline] copy_process+0x80b/0x84c0 kernel/fork.c:2141 kernel_clone+0x176/0x9d0 kernel/fork.c:2783 user_mode_thread+0xd1/0x120 kernel/fork.c:2860 call_usermodehelper_exec_work kernel/umh.c:169 [inline] call_usermodehelper_exec_work+0xcb/0x180 kernel/umh.c:155 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3495 process_scheduled_works kernel/workqueue.c:3578 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3659 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888030bb3c80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888030bb3d00: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc >ffff888030bb3d80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff888030bb3e00: 00 00 00 00 00 00 00 00 00 03 fc fc fc fc fc fc ffff888030bb3e80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup