================================================================== BUG: KASAN: use-after-free in crc16+0x1c0/0x280 lib/crc16.c:58 Read of size 1 at addr ffff88801d210000 by task syz-executor.0/29485 CPU: 0 PID: 29485 Comm: syz-executor.0 Not tainted 6.2.0-rc8-syzkaller-00021-ge1c04510f521 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x163/0x4f0 mm/kasan/report.c:417 kasan_report+0x13a/0x170 mm/kasan/report.c:517 crc16+0x1c0/0x280 lib/crc16.c:58 ext4_group_desc_csum+0x90f/0xc50 fs/ext4/super.c:3187 ext4_group_desc_csum_set+0x19b/0x240 fs/ext4/super.c:3210 ext4_mb_mark_diskspace_used+0xbeb/0x1480 fs/ext4/mballoc.c:3826 ext4_mb_new_blocks+0x1418/0x4b30 fs/ext4/mballoc.c:5623 ext4_ext_map_blocks+0x1d18/0x7c20 fs/ext4/extents.c:4286 ext4_map_blocks+0xa4c/0x1cf0 fs/ext4/inode.c:651 _ext4_get_block+0x23f/0x670 fs/ext4/inode.c:808 ext4_block_write_begin+0x635/0x1400 fs/ext4/inode.c:1098 ext4_write_begin+0x6dc/0x1050 ext4_da_write_begin+0x4c2/0xac0 fs/ext4/inode.c:3058 generic_perform_write+0x300/0x5e0 mm/filemap.c:3772 ext4_buffered_write_iter+0x122/0x3a0 fs/ext4/file.c:285 ext4_file_write_iter+0x1d6/0x1910 call_write_iter include/linux/fs.h:2189 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x7b2/0xbb0 fs/read_write.c:584 ksys_write+0x1a0/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f019068c0f9 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:00007f0191471168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f01907abf80 RCX: 00007f019068c0f9 RDX: 0000000000000009 RSI: 0000000020000440 RDI: 0000000000000006 RBP: 00007f01906e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd323ab68f R14: 00007f0191471300 R15: 0000000000022000 Allocated by task 29330: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x80 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x9b/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:968 [inline] __kmalloc_node+0xb3/0x190 mm/slab_common.c:975 kmalloc_node include/linux/slab.h:610 [inline] kvmalloc_node+0x72/0x180 mm/util.c:581 kvmalloc include/linux/slab.h:737 [inline] seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x202/0xd10 fs/seq_file.c:210 call_read_iter include/linux/fs.h:2183 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x7e2/0xbe0 fs/read_write.c:470 ksys_read+0x1a0/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 29330: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x80 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:523 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook mm/slub.c:1807 [inline] slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0x264/0x3c0 mm/slub.c:3800 seq_release+0x57/0x70 fs/seq_file.c:355 kernfs_fop_release+0x133/0x190 fs/kernfs/file.c:806 __fput+0x3b7/0x890 fs/file_table.c:320 task_work_run+0x24a/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x64/0x2e0 kernel/entry/common.c:296 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88801d210000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 0 bytes inside of 4096-byte region [ffff88801d210000, ffff88801d211000) The buggy address belongs to the physical page: page:ffffea0000748400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d210 head:ffffea0000748400 order:3 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 memcg:ffff88807f2e8501 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff88801244f500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88807f2e8501 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 23634, tgid 23634 (udevadm), ts 735980830100, free_ts 735967132974 prep_new_page mm/page_alloc.c:2531 [inline] get_page_from_freelist+0x3449/0x35c0 mm/page_alloc.c:4283 __alloc_pages+0x291/0x7e0 mm/page_alloc.c:5549 alloc_slab_page+0x6a/0x160 mm/slub.c:1851 allocate_slab mm/slub.c:1998 [inline] new_slab+0x84/0x2f0 mm/slub.c:2051 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3193 __slab_alloc mm/slub.c:3292 [inline] __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x1b8/0x2a0 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:967 [inline] __kmalloc_node+0xa2/0x190 mm/slab_common.c:975 kmalloc_node include/linux/slab.h:610 [inline] kvmalloc_node+0x72/0x180 mm/util.c:581 kvmalloc include/linux/slab.h:737 [inline] seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x202/0xd10 fs/seq_file.c:210 call_read_iter include/linux/fs.h:2183 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x7e2/0xbe0 fs/read_write.c:470 ksys_read+0x1a0/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1446 [inline] free_pcp_prepare mm/page_alloc.c:1496 [inline] free_unref_page_prepare+0xf3a/0x1040 mm/page_alloc.c:3369 free_unref_page+0x37/0x3f0 mm/page_alloc.c:3464 discard_slab mm/slub.c:2098 [inline] __unfreeze_partials+0x1b1/0x1f0 mm/slub.c:2637 put_cpu_partial+0x116/0x180 mm/slub.c:2713 qlist_free_all+0x22/0x60 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x15a/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x68/0x390 mm/slab.h:761 slab_alloc_node mm/slub.c:3452 [inline] __kmem_cache_alloc_node+0x14c/0x2a0 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:967 [inline] __kmalloc_node+0xa2/0x190 mm/slab_common.c:975 kmalloc_array_node include/linux/slab.h:697 [inline] kcalloc_node include/linux/slab.h:702 [inline] memcg_alloc_slab_cgroups+0x81/0x120 mm/memcontrol.c:2889 account_slab mm/slab.h:645 [inline] allocate_slab mm/slub.c:2016 [inline] new_slab+0xc0/0x2f0 mm/slub.c:2051 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3193 __slab_alloc mm/slub.c:3292 [inline] __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x1b8/0x2a0 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:967 [inline] __kmalloc_node+0xa2/0x190 mm/slab_common.c:975 kmalloc_node include/linux/slab.h:610 [inline] kvmalloc_node+0x72/0x180 mm/util.c:581 Memory state around the buggy address: ffff88801d20ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801d20ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88801d210000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801d210080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801d210100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================