Hello, syzbot found the following issue on: HEAD commit: fbafc3e621c3 Merge tag 'for_linus' of git://git.kernel.org.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=11b0a595e80000 kernel config: https://syzkaller.appspot.com/x/.config?x=e0c7078a6b901aa3 dashboard link: https://syzkaller.appspot.com/bug?extid=6c746eea496f34b3161d 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=169fac19e80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14aafc81e80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/1520f7b6daa4/disk-fbafc3e6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/8b490af009d5/vmlinux-fbafc3e6.xz kernel image: https://storage.googleapis.com/syzbot-assets/202ca200f4a4/bzImage-fbafc3e6.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/fcf70b38bafb/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6c746eea496f34b3161d@xxxxxxxxxxxxxxxxxxxxxxxxx loop0: detected capacity change from 0 to 16 erofs: (device loop0): mounted with root inode @ nid 36. erofs: (device loop0): z_erofs_lz4_decompress_mem: failed to decompress -12 in[46, 4050] out[917] ===================================================== BUG: KMSAN: uninit-value in hex_dump_to_buffer+0xae9/0x10f0 lib/hexdump.c:194 hex_dump_to_buffer+0xae9/0x10f0 lib/hexdump.c:194 print_hex_dump+0x13d/0x3e0 lib/hexdump.c:276 z_erofs_lz4_decompress_mem fs/erofs/decompressor.c:252 [inline] z_erofs_lz4_decompress+0x257e/0x2a70 fs/erofs/decompressor.c:311 z_erofs_decompress_pcluster fs/erofs/zdata.c:1290 [inline] z_erofs_decompress_queue+0x338c/0x6460 fs/erofs/zdata.c:1372 z_erofs_runqueue+0x36cd/0x3830 z_erofs_read_folio+0x435/0x810 fs/erofs/zdata.c:1843 filemap_read_folio+0xce/0x370 mm/filemap.c:2323 do_read_cache_folio+0x3b4/0x11e0 mm/filemap.c:3691 read_cache_folio+0x60/0x80 mm/filemap.c:3723 erofs_bread+0x286/0x6f0 fs/erofs/data.c:46 erofs_find_target_block fs/erofs/namei.c:103 [inline] erofs_namei+0x2fe/0x1790 fs/erofs/namei.c:177 erofs_lookup+0x100/0x3c0 fs/erofs/namei.c:206 lookup_one_qstr_excl+0x233/0x520 fs/namei.c:1609 filename_create+0x2fc/0x6d0 fs/namei.c:3876 do_mkdirat+0x69/0x800 fs/namei.c:4121 __do_sys_mkdirat fs/namei.c:4144 [inline] __se_sys_mkdirat fs/namei.c:4142 [inline] __x64_sys_mkdirat+0xc8/0x120 fs/namei.c:4142 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was created at: __alloc_pages+0x9a4/0xe00 mm/page_alloc.c:4591 alloc_pages_mpol+0x62b/0x9d0 mm/mempolicy.c:2133 alloc_pages mm/mempolicy.c:2204 [inline] folio_alloc+0x1da/0x380 mm/mempolicy.c:2211 filemap_alloc_folio+0xa5/0x430 mm/filemap.c:974 do_read_cache_folio+0x163/0x11e0 mm/filemap.c:3655 read_cache_folio+0x60/0x80 mm/filemap.c:3723 erofs_bread+0x286/0x6f0 fs/erofs/data.c:46 erofs_find_target_block fs/erofs/namei.c:103 [inline] erofs_namei+0x2fe/0x1790 fs/erofs/namei.c:177 erofs_lookup+0x100/0x3c0 fs/erofs/namei.c:206 lookup_one_qstr_excl+0x233/0x520 fs/namei.c:1609 filename_create+0x2fc/0x6d0 fs/namei.c:3876 do_mkdirat+0x69/0x800 fs/namei.c:4121 __do_sys_mkdirat fs/namei.c:4144 [inline] __se_sys_mkdirat fs/namei.c:4142 [inline] __x64_sys_mkdirat+0xc8/0x120 fs/namei.c:4142 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b CPU: 1 PID: 5006 Comm: syz-executor342 Not tainted 6.7.0-rc7-syzkaller-00003-gfbafc3e621c3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 ===================================================== --- 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 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