loop0: detected capacity change from 0 to 64 hfs: unable to locate alternate MDB hfs: continuing without an alternate MDB Oops: general protection fault, probably for non-canonical address 0xdffffc0000000008: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000040-0x0000000000000047] CPU: 0 UID: 0 PID: 5992 Comm: syz-executor766 Not tainted 6.16.0-rc3-syzkaller-00072-gee88bddf7f2f #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:hfs_find_init+0x6a/0x1e0 fs/hfs/bfind.c:21 Code: 7e 18 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 b8 b4 8a ff 49 c7 07 00 00 00 00 48 8d 6b 40 49 89 ef 49 c1 ef 03 <43> 0f b6 04 2f 84 c0 0f 85 0c 01 00 00 8b 45 00 8d 3c 45 04 00 00 RSP: 0018:ffffc9000448f588 EFLAGS: 00010202 RAX: 1ffff92000891ecf RBX: 0000000000000000 RCX: ffff8880790bda00 RDX: 0000000000000000 RSI: ffffc9000448f660 RDI: ffffc9000448f670 RBP: 0000000000000040 R08: ffffc9000448f697 R09: 0000000000000000 R10: ffffc9000448f660 R11: fffff52000891ed3 R12: ffff88807c10c640 R13: dffffc0000000000 R14: ffffc9000448f660 R15: 0000000000000008 FS: 00007f62875f06c0(0000) GS:ffff888125c85000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff690947000 CR3: 0000000033252000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_get_block+0x51b/0xbd0 fs/hfs/extent.c:366 block_read_full_folio+0x29c/0x830 fs/buffer.c:2427 filemap_read_folio+0x117/0x380 mm/filemap.c:2412 do_read_cache_folio+0x350/0x590 mm/filemap.c:3894 do_read_cache_page mm/filemap.c:3960 [inline] read_cache_page+0x5d/0x170 mm/filemap.c:3969 read_mapping_page include/linux/pagemap.h:966 [inline] hfs_btree_open+0x55f/0x14f0 fs/hfs/btree.c:78 hfs_mdb_get+0x1327/0x2080 fs/hfs/mdb.c:199 hfs_fill_super+0x37b/0x640 fs/hfs/super.c:337 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1681 vfs_get_tree+0x8f/0x2b0 fs/super.c:1804 do_new_mount+0x24a/0xa40 fs/namespace.c:3902 do_mount fs/namespace.c:4239 [inline] __do_sys_mount fs/namespace.c:4450 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4427 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f628763ceea 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f62875f0088 EFLAGS: 00000286 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f62875f00a0 RCX: 00007f628763ceea RDX: 0000200000000000 RSI: 0000200000000100 RDI: 00007f62875f00a0 RBP: 0000200000000100 R08: 00007f62875f00e0 R09: 0000000000000333 R10: 0000000000000012 R11: 0000000000000286 R12: 0000200000000000 R13: 00007f62875f00e0 R14: 0000000000000003 R15: 0000000000000012 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:hfs_find_init+0x6a/0x1e0 fs/hfs/bfind.c:21 Code: 7e 18 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 b8 b4 8a ff 49 c7 07 00 00 00 00 48 8d 6b 40 49 89 ef 49 c1 ef 03 <43> 0f b6 04 2f 84 c0 0f 85 0c 01 00 00 8b 45 00 8d 3c 45 04 00 00 RSP: 0018:ffffc9000448f588 EFLAGS: 00010202 RAX: 1ffff92000891ecf RBX: 0000000000000000 RCX: ffff8880790bda00 RDX: 0000000000000000 RSI: ffffc9000448f660 RDI: ffffc9000448f670 RBP: 0000000000000040 R08: ffffc9000448f697 R09: 0000000000000000 R10: ffffc9000448f660 R11: fffff52000891ed3 R12: ffff88807c10c640 R13: dffffc0000000000 R14: ffffc9000448f660 R15: 0000000000000008 FS: 00007f62875f06c0(0000) GS:ffff888125c85000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff690947000 CR3: 0000000033252000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 7e 18 jle 0x1a 2: 4c 89 f8 mov %r15,%rax 5: 48 c1 e8 03 shr $0x3,%rax 9: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) e: 74 08 je 0x18 10: 4c 89 ff mov %r15,%rdi 13: e8 b8 b4 8a ff call 0xff8ab4d0 18: 49 c7 07 00 00 00 00 movq $0x0,(%r15) 1f: 48 8d 6b 40 lea 0x40(%rbx),%rbp 23: 49 89 ef mov %rbp,%r15 26: 49 c1 ef 03 shr $0x3,%r15 * 2a: 43 0f b6 04 2f movzbl (%r15,%r13,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 0c 01 00 00 jne 0x143 37: 8b 45 00 mov 0x0(%rbp),%eax 3a: 8d .byte 0x8d 3b: 3c 45 cmp $0x45,%al 3d: 04 00 add $0x0,%al