hfs: unable to locate alternate MDB hfs: continuing without an alternate MDB kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 0 PID: 4467 Comm: syzkaller143800 Not tainted 4.16.0-rc7+ #9 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:hfs_find_init+0x76/0x180 fs/hfs/bfind.c:21 RSP: 0018:ffff8801acbe6bd0 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffff8801acbe6c58 RCX: ffffffff820dd056 RDX: 0000000000000008 RSI: ffff8801acbe6c58 RDI: ffff8801acbe6c70 RBP: ffff8801acbe6bf0 R08: ffffffff820f0430 R09: 0000000000000000 R10: ffff8801acbe6ce0 R11: ffffed003597cc6f R12: 0000000000000000 R13: 0000000000000040 R14: ffff8801ad972080 R15: ffff8801acbe6cb8 FS: 0000000001e2d880(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe9b457a9b8 CR3: 00000001ac89e004 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hfs_ext_read_extent+0x197/0xb50 fs/hfs/extent.c:196 hfs_get_block+0x4cc/0x7a0 fs/hfs/extent.c:360 block_read_full_page+0x293/0x990 fs/buffer.c:2259 hfs_readpage+0x1c/0x20 fs/hfs/inode.c:38 do_read_cache_page+0x637/0x11b0 mm/filemap.c:2804 read_cache_page+0x61/0x80 mm/filemap.c:2892 read_mapping_page include/linux/pagemap.h:402 [inline] hfs_btree_open+0x536/0x1630 fs/hfs/btree.c:78 hfs_mdb_get+0x16ab/0x22c0 fs/hfs/mdb.c:193 hfs_fill_super+0x1023/0x1930 fs/hfs/super.c:413 mount_bdev+0x2b7/0x370 fs/super.c:1119 hfs_mount+0x34/0x40 fs/hfs/super.c:463 mount_fs+0x66/0x2d0 fs/super.c:1222 vfs_kern_mount.part.26+0xc6/0x4a0 fs/namespace.c:1037 vfs_kern_mount fs/namespace.c:2509 [inline] do_new_mount fs/namespace.c:2512 [inline] do_mount+0xea4/0x2bb0 fs/namespace.c:2842 SYSC_mount fs/namespace.c:3058 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3035 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x442daa RSP: 002b:00007ffd0232faf8 EFLAGS: 00000297 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000258 RCX: 0000000000442daa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffd0232fb00 RBP: 0000000000000003 R08: 00000000200001c0 R09: 000000000000000a R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000004 R13: 0000000000401ca0 R14: 0000000000000000 R15: 0000000000000000 Code: c1 ea 03 80 3c 02 00 0f 85 f2 00 00 00 4d 8d 6c 24 40 48 b8 00 00 00 00 00 fc ff df 48 c7 43 18 00 00 00 00 4c 89 ea 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e b0 00 00 00 41 8b 44 24 40 RIP: hfs_find_init+0x76/0x180 fs/hfs/bfind.c:21 RSP: ffff8801acbe6bd0 ---[ end trace 5617fd7a7b5bfbcd ]---