Hello, syzbot found the following issue on: HEAD commit: 69b8923f5003 Merge tag 'for-linus-6.14-ofs4' of git://git... git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=1258aeb0580000 kernel config: https://syzkaller.appspot.com/x/.config?x=57ab43c279fa614d dashboard link: https://syzkaller.appspot.com/bug?extid=48a99e426f29859818c0 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=15825724580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1658aeb0580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/ea84ac864e92/disk-69b8923f.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6a465997b4e0/vmlinux-69b8923f.xz kernel image: https://storage.googleapis.com/syzbot-assets/d72b67b2bd15/bzImage-69b8923f.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/7c2919610764/mount_0.gz The issue was bisected to: commit bae80473f7b0b25772619e7692019b1549d4a82c Author: Mateusz Guzik <mjguzik@xxxxxxxxx> Date: Wed Nov 20 11:20:35 2024 +0000 ext4: use inode_set_cached_link() bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1248c3df980000 final oops: https://syzkaller.appspot.com/x/report.txt?x=1148c3df980000 console output: https://syzkaller.appspot.com/x/log.txt?x=1648c3df980000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+48a99e426f29859818c0@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: bae80473f7b0 ("ext4: use inode_set_cached_link()") EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback. usercopy: Kernel memory exposure attempt detected from SLUB object 'ext4_inode_cache' (offset 0, size 176)! ------------[ cut here ]------------ kernel BUG at mm/usercopy.c:102! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 UID: 0 PID: 5826 Comm: syz-executor349 Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:usercopy_abort+0x84/0x90 mm/usercopy.c:102 Code: 49 89 ce 48 c7 c3 80 5f 18 8c 48 0f 44 de 48 c7 c7 20 5e 18 8c 4c 89 de 48 89 c1 41 52 41 56 53 e8 d1 3a f5 fe 48 83 c4 18 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90003fa7c90 EFLAGS: 00010296 RAX: 000000000000006b RBX: ffffffff8c185f80 RCX: ba71ae4bd9cf0200 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff819f1fbc R09: 1ffff920007f4f2c R10: dffffc0000000000 R11: fffff520007f4f2d R12: ffffea0001e70200 R13: 00000000000000b0 R14: 0000000000000000 R15: 00000000000000b0 FS: 00005555602a7380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000066c7e0 CR3: 0000000078aac000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __check_heap_object+0xb1/0x100 mm/slub.c:5818 check_heap_object mm/usercopy.c:196 [inline] __check_object_size+0x1da/0x730 mm/usercopy.c:251 check_object_size include/linux/thread_info.h:228 [inline] check_copy_size include/linux/thread_info.h:264 [inline] copy_to_user include/linux/uaccess.h:219 [inline] readlink_copy fs/namei.c:5284 [inline] vfs_readlink+0x1cf/0x550 fs/namei.c:5307 do_readlinkat+0x249/0x3a0 fs/stat.c:576 __do_sys_readlinkat fs/stat.c:593 [inline] __se_sys_readlinkat fs/stat.c:590 [inline] __x64_sys_readlinkat+0x9a/0xb0 fs/stat.c:590 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdaffabc639 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:00007ffeb88c4948 EFLAGS: 00000246 ORIG_RAX: 000000000000010b RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007fdaffabc639 RDX: 00000000200002c0 RSI: 0000000020000240 RDI: 00000000ffffff9c RBP: 00007fdaffb30610 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000000b0 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffeb88c4b18 R14: 0000000000000001 R15: 0000000000000001 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:usercopy_abort+0x84/0x90 mm/usercopy.c:102 Code: 49 89 ce 48 c7 c3 80 5f 18 8c 48 0f 44 de 48 c7 c7 20 5e 18 8c 4c 89 de 48 89 c1 41 52 41 56 53 e8 d1 3a f5 fe 48 83 c4 18 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90003fa7c90 EFLAGS: 00010296 RAX: 000000000000006b RBX: ffffffff8c185f80 RCX: ba71ae4bd9cf0200 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff819f1fbc R09: 1ffff920007f4f2c R10: dffffc0000000000 R11: fffff520007f4f2d R12: ffffea0001e70200 R13: 00000000000000b0 R14: 0000000000000000 R15: 00000000000000b0 FS: 00005555602a7380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055dd00353bf8 CR3: 0000000078aac000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 --- 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
