Hello, syzbot found the following issue on: HEAD commit: 3bd7d7488169 Merge tag 'io_uring-6.7-2023-12-15' of git://.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=13732cc6e80000 kernel config: https://syzkaller.appspot.com/x/.config?x=53ec3da1d259132f dashboard link: https://syzkaller.appspot.com/bug?extid=33f23b49ac24f986c9e8 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16d8ba06e80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=136fd5b2e80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/99b3f103aa0b/disk-3bd7d748.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/32f8e3e696ce/vmlinux-3bd7d748.xz kernel image: https://storage.googleapis.com/syzbot-assets/cb20a5445c11/bzImage-3bd7d748.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/4f5365674997/mount_0.gz The issue was bisected to: commit 9974d37ea75f01b47d16072b5dad305bd8d23fcc Author: Liu Jian <liujian56@xxxxxxxxxx> Date: Tue Jun 28 12:36:16 2022 +0000 skmsg: Fix invalid last sg check in sk_msg_recvmsg() bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=172b998ae80000 final oops: https://syzkaller.appspot.com/x/report.txt?x=14ab998ae80000 console output: https://syzkaller.appspot.com/x/log.txt?x=10ab998ae80000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+33f23b49ac24f986c9e8@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 9974d37ea75f ("skmsg: Fix invalid last sg check in sk_msg_recvmsg()") BTRFS info (device loop0): clearing compat-ro feature flag for FREE_SPACE_TREE_VALID (0x2) ================================================================== BUG: KASAN: slab-out-of-bounds in strlen+0x58/0x70 lib/string.c:418 Read of size 1 at addr ffff88801d7f2a28 by task syz-executor424/5057 CPU: 1 PID: 5057 Comm: syz-executor424 Not tainted 6.7.0-rc5-syzkaller-00200-g3bd7d7488169 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x142/0x170 mm/kasan/report.c:588 strlen+0x58/0x70 lib/string.c:418 getname_kernel+0x1d/0x2e0 fs/namei.c:226 kern_path+0x1d/0x50 fs/namei.c:2609 lookup_bdev block/bdev.c:979 [inline] bdev_open_by_path+0xd1/0x540 block/bdev.c:901 btrfs_init_dev_replace_tgtdev fs/btrfs/dev-replace.c:260 [inline] btrfs_dev_replace_start fs/btrfs/dev-replace.c:638 [inline] btrfs_dev_replace_by_ioctl+0x41b/0x2010 fs/btrfs/dev-replace.c:747 btrfs_ioctl_dev_replace+0x2c9/0x390 fs/btrfs/ioctl.c:3299 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f8e8ffdc079 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe15cbe138 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffe15cbe308 RCX: 00007f8e8ffdc079 RDX: 0000000020000540 RSI: 00000000ca289435 RDI: 0000000000000005 RBP: 00007f8e90054610 R08: 00007ffe15cbe308 R09: 00007ffe15cbe308 R10: 00007ffe15cbe308 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe15cbe2f8 R14: 0000000000000001 R15: 0000000000000001 </TASK> Allocated by task 5057: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node_track_caller+0xb1/0x190 mm/slab_common.c:1027 memdup_user+0x2b/0xc0 mm/util.c:197 btrfs_ioctl_dev_replace+0xb8/0x390 fs/btrfs/ioctl.c:3286 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff88801d7f2000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 0 bytes to the right of allocated 2600-byte region [ffff88801d7f2000, ffff88801d7f2a28) The buggy address belongs to the physical page: page:ffffea000075fc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d7f0 head:ffffea000075fc00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888012c42140 ffffea00007b5600 0000000000000002 raw: 0000000000000000 0000000080040004 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4716, tgid 4716 (ifup), ts 29920494589, free_ts 29905444571 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0x33ea/0x3570 mm/page_alloc.c:3312 __alloc_pages+0x255/0x680 mm/page_alloc.c:4568 alloc_pages_mpol+0x3de/0x640 mm/mempolicy.c:2133 alloc_slab_page+0x6a/0x170 mm/slub.c:1870 allocate_slab mm/slub.c:2017 [inline] new_slab+0x84/0x2f0 mm/slub.c:2070 ___slab_alloc+0xc8a/0x1330 mm/slub.c:3223 __slab_alloc mm/slub.c:3322 [inline] __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x21d/0x300 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa2/0x1a0 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x255/0x500 security/tomoyo/file.c:771 security_file_open+0x63/0xa0 security/security.c:2836 do_dentry_open+0x327/0x1590 fs/open.c:935 do_open fs/namei.c:3622 [inline] path_openat+0x2849/0x3290 fs/namei.c:3779 do_filp_open+0x234/0x490 fs/namei.c:3809 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1137 [inline] free_unref_page_prepare+0x931/0xa60 mm/page_alloc.c:2347 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487 discard_slab mm/slub.c:2116 [inline] __unfreeze_partials+0x1e0/0x220 mm/slub.c:2655 put_cpu_partial+0x17b/0x250 mm/slub.c:2731 __slab_free+0x2b6/0x390 mm/slub.c:3679 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x14b/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x23/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6c/0x3c0 mm/slab.h:763 slab_alloc_node mm/slub.c:3478 [inline] __kmem_cache_alloc_node+0x1d0/0x300 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa2/0x1a0 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2b7/0x730 security/tomoyo/file.c:822 security_inode_getattr+0xd3/0x120 security/security.c:2153 vfs_getattr+0x46/0x430 fs/stat.c:173 vfs_fstat fs/stat.c:198 [inline] vfs_fstatat+0xd6/0x190 fs/stat.c:295 Memory state around the buggy address: ffff88801d7f2900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801d7f2980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88801d7f2a00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88801d7f2a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801d7f2b00: 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. For information about bisection process see: https://goo.gl/tpsmEJ#bisection 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