loop0: detected capacity change from 0 to 2048 EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 without journal. Quota mode: none. ext4 filesystem being mounted at /root/syzkaller-testdir2349860770/syzkaller.UarDul/1/bus supports timestamps until 2038-01-19 (0x7fffffff) ================================================================== BUG: KASAN: slab-out-of-bounds in crc16+0x21a/0x2a0 lib/crc16.c:58 Read of size 1 at addr ffff8881207e5000 by task syz-executor.0/348 CPU: 1 PID: 348 Comm: syz-executor.0 Not tainted 6.3.0-syzkaller-13027-g1a5304fecee5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x155/0x1c0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:351 [inline] print_report+0x15d/0x540 mm/kasan/report.c:462 kasan_report+0x16d/0x1a0 mm/kasan/report.c:572 __asan_report_load1_noabort+0x18/0x20 mm/kasan/report_generic.c:378 crc16+0x21a/0x2a0 lib/crc16.c:58 ext4_group_desc_csum+0x90f/0xc50 fs/ext4/super.c:3243 ext4_group_desc_csum_set+0x1dc/0x280 fs/ext4/super.c:3266 ext4_mb_clear_bb fs/ext4/mballoc.c:6206 [inline] ext4_free_blocks+0x1b14/0x2b90 fs/ext4/mballoc.c:6352 ext4_remove_blocks fs/ext4/extents.c:2527 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2710 [inline] ext4_ext_remove_space+0x27aa/0x4ef0 fs/ext4/extents.c:2958 ext4_ext_truncate+0x1f8/0x320 fs/ext4/extents.c:4416 ext4_truncate+0x976/0xfc0 fs/ext4/inode.c:4151 ext4_evict_inode+0xa1d/0x12d0 fs/ext4/inode.c:258 evict+0x2a3/0x630 fs/inode.c:665 iput_final fs/inode.c:1747 [inline] iput+0x64a/0x880 fs/inode.c:1773 do_unlinkat+0x4e5/0x920 fs/namei.c:4400 __do_sys_unlink fs/namei.c:4441 [inline] __se_sys_unlink fs/namei.c:4439 [inline] __x64_sys_unlink+0x4d/0x60 fs/namei.c:4439 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7ff136c8c0f9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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:00007ff137a26168 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 00007ff136dabf80 RCX: 00007ff136c8c0f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000200 RBP: 00007ff136ce7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd3d5e1e2f R14: 00007ff137a26300 R15: 0000000000022000 The buggy address belongs to the object at ffff8881207e5000 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 0 bytes inside of allocated 64-byte region [ffff8881207e5000, ffff8881207e5040) The buggy address belongs to the physical page: page:ffffea000481f940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1207e5 flags: 0x4000000000000200(slab|zone=1) page_type: 0xffffffff() raw: 4000000000000200 ffff888100041640 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 348, tgid 347 (syz-executor.0), ts 37328091310, free_ts 37320828815 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x223/0x230 mm/page_alloc.c:1722 prep_new_page mm/page_alloc.c:1729 [inline] get_page_from_freelist+0x3442/0x3510 mm/page_alloc.c:3493 __alloc_pages+0x3e7/0x890 mm/page_alloc.c:4759 allocate_slab mm/slub.c:1998 [inline] new_slab+0xce/0x4d0 mm/slub.c:2051 ___slab_alloc+0x701/0xb90 mm/slub.c:3192 __slab_alloc mm/slub.c:3291 [inline] __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] __kmem_cache_alloc_node+0x188/0x240 mm/slub.c:3490 kmalloc_trace+0x2e/0xb0 mm/slab_common.c:1057 kmalloc include/linux/slab.h:559 [inline] kmalloc_array include/linux/slab.h:595 [inline] kcalloc include/linux/slab.h:627 [inline] __list_lru_init+0xaa/0x370 mm/list_lru.c:571 alloc_super+0x6a1/0x7c0 fs/super.c:272 sget_fc+0x213/0x620 fs/super.c:581 get_tree_bdev+0x285/0x670 fs/super.c:1271 ext4_get_tree+0x20/0x30 fs/ext4/super.c:5703 vfs_get_tree+0x8c/0x290 fs/super.c:1510 do_new_mount+0x28f/0xad0 fs/namespace.c:3039 path_mount+0x677/0x1000 fs/namespace.c:3369 do_mount fs/namespace.c:3382 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount+0x2c8/0x3b0 fs/namespace.c:3568 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1302 [inline] free_unref_page_prepare+0x462/0x6a0 mm/page_alloc.c:2555 free_unref_page+0x3a/0x390 mm/page_alloc.c:2650 free_the_page mm/page_alloc.c:661 [inline] __free_pages+0x65/0x100 mm/page_alloc.c:4848 free_pages+0x80/0x90 mm/page_alloc.c:4859 tlb_batch_list_free mm/mmu_gather.c:113 [inline] tlb_finish_mmu+0x125/0x1f0 mm/mmu_gather.c:394 unmap_region+0x258/0x2a0 mm/mmap.c:2222 do_vmi_align_munmap+0xa08/0x1000 mm/mmap.c:2473 do_vmi_munmap+0x242/0x2b0 mm/mmap.c:2530 __vm_munmap+0x200/0x340 mm/mmap.c:2805 __do_sys_munmap mm/mmap.c:2830 [inline] __se_sys_munmap mm/mmap.c:2827 [inline] __x64_sys_munmap+0x64/0x70 mm/mmap.c:2827 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff8881207e4f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881207e4f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881207e5000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881207e5080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881207e5100: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ==================================================================