Hello, syzbot found the following issue on: HEAD commit: f7dc24b34138 Add linux-next specific files for 20230807 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=12a0862ba80000 kernel config: https://syzkaller.appspot.com/x/.config?x=d7847c9dca13d6c5 dashboard link: https://syzkaller.appspot.com/bug?extid=26860029a4d562566231 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=179704c9a80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17868ba9a80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/24eb0299fcf6/disk-f7dc24b3.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d1dc5212ed72/vmlinux-f7dc24b3.xz kernel image: https://storage.googleapis.com/syzbot-assets/062c8c075e0c/bzImage-f7dc24b3.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/8e4e0cc06a40/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+26860029a4d562566231@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in btrfs_open_devices+0xb8/0xc0 fs/btrfs/volumes.c:1281 Read of size 4 at addr ffff8880293c8d30 by task syz-executor243/5048 CPU: 0 PID: 5048 Comm: syz-executor243 Not tainted 6.5.0-rc5-next-20230807-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 btrfs_open_devices+0xb8/0xc0 fs/btrfs/volumes.c:1281 btrfs_mount_root+0x681/0xda0 fs/btrfs/super.c:1505 legacy_get_tree+0x109/0x220 fs/fs_context.c:611 vfs_get_tree+0x88/0x350 fs/super.c:1544 fc_mount fs/namespace.c:1112 [inline] vfs_kern_mount.part.0+0xcb/0x170 fs/namespace.c:1142 vfs_kern_mount+0x3f/0x60 fs/namespace.c:1129 btrfs_mount+0x292/0xb10 fs/btrfs/super.c:1578 legacy_get_tree+0x109/0x220 fs/fs_context.c:611 vfs_get_tree+0x88/0x350 fs/super.c:1544 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fc50e075e9a Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd2e2532d8 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007ffd2e2532f0 RCX: 00007fc50e075e9a RDX: 00000000200051c0 RSI: 0000000020005200 RDI: 00007ffd2e2532f0 RBP: 0000000000000004 R08: 00007ffd2e253330 R09: 00000000000051a5 R10: 0000000001000008 R11: 0000000000000282 R12: 0000000001000008 R13: 00007ffd2e253330 R14: 0000000000000003 R15: 0000000001000000 </TASK> Allocated by task 5043: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] kzalloc include/linux/slab.h:720 [inline] alloc_fs_devices+0x54/0x2b0 fs/btrfs/volumes.c:375 device_list_add.constprop.0+0x3eb/0x1db0 fs/btrfs/volumes.c:807 btrfs_scan_one_device+0x1b7/0x2a0 fs/btrfs/volumes.c:1405 btrfs_mount_root+0x4a8/0xda0 fs/btrfs/super.c:1482 legacy_get_tree+0x109/0x220 fs/fs_context.c:611 vfs_get_tree+0x88/0x350 fs/super.c:1544 fc_mount fs/namespace.c:1112 [inline] vfs_kern_mount.part.0+0xcb/0x170 fs/namespace.c:1142 vfs_kern_mount+0x3f/0x60 fs/namespace.c:1129 btrfs_mount+0x292/0xb10 fs/btrfs/super.c:1578 legacy_get_tree+0x109/0x220 fs/fs_context.c:611 vfs_get_tree+0x88/0x350 fs/super.c:1544 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5043: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15e/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3822 btrfs_close_devices+0x4cd/0x610 fs/btrfs/volumes.c:1207 open_ctree+0x1c1/0x5710 fs/btrfs/disk-io.c:3612 btrfs_fill_super fs/btrfs/super.c:1158 [inline] btrfs_mount_root+0x976/0xda0 fs/btrfs/super.c:1520 legacy_get_tree+0x109/0x220 fs/fs_context.c:611 vfs_get_tree+0x88/0x350 fs/super.c:1544 fc_mount fs/namespace.c:1112 [inline] vfs_kern_mount.part.0+0xcb/0x170 fs/namespace.c:1142 vfs_kern_mount+0x3f/0x60 fs/namespace.c:1129 btrfs_mount+0x292/0xb10 fs/btrfs/super.c:1578 legacy_get_tree+0x109/0x220 fs/fs_context.c:611 vfs_get_tree+0x88/0x350 fs/super.c:1544 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880293c8c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 304 bytes inside of freed 512-byte region [ffff8880293c8c00, ffff8880293c8e00) The buggy address belongs to the physical page: page:ffffea0000a4f200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x293c8 head:ffffea0000a4f200 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000010200 ffff888012841c80 ffffea00008f2d00 dead000000000002 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4147, tgid 4147 (kworker/u4:3), ts 10970429937, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d2/0x350 mm/page_alloc.c:1567 prep_new_page mm/page_alloc.c:1574 [inline] get_page_from_freelist+0x10d7/0x31b0 mm/page_alloc.c:3253 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4509 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2298 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x24e/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8bc/0x1570 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x137/0x350 mm/slub.c:3517 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1114 kmalloc include/linux/slab.h:599 [inline] kzalloc include/linux/slab.h:720 [inline] alloc_bprm+0x51/0xaf0 fs/exec.c:1514 kernel_execve+0xaf/0x4e0 fs/exec.c:1989 call_usermodehelper_exec_async+0x256/0x4c0 kernel/umh.c:110 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 page_owner free stack trace missing Memory state around the buggy address: ffff8880293c8c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880293c8c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880293c8d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880293c8d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880293c8e00: fc fc fc fc fc fc fc fc fc fc fc fc 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@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, 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 change bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
