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BUG: KASAN: slab-out-of-bounds in iov_iter_alignment+0x6a1/0x7b0 lib/iov_iter.c:1225
Read of size 4 at addr ffff8880a03de7d4 by task syz-executor.0/12312

CPU: 1 PID: 12312 Comm: syz-executor.0 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fb/0x318 lib/dump_stack.c:118
 print_address_description+0x75/0x5c0 mm/kasan/report.c:374
 __kasan_report+0x14b/0x1c0 mm/kasan/report.c:506
 kasan_report+0x26/0x50 mm/kasan/common.c:634
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 iov_iter_alignment+0x6a1/0x7b0 lib/iov_iter.c:1225
 iomap_dio_bio_actor+0x1a7/0x11e0 fs/iomap/direct-io.c:203
 iomap_dio_actor+0x2b4/0x4a0 fs/iomap/direct-io.c:375
 iomap_apply+0x370/0x490 fs/iomap/apply.c:80
 iomap_dio_rw+0x8ad/0x1010 fs/iomap/direct-io.c:493
 ext4_dio_write_iter fs/ext4/file.c:438 [inline]
 ext4_file_write_iter+0x15a4/0x1f50 fs/ext4/file.c:545
 do_iter_readv_writev+0x651/0x8e0 include/linux/fs.h:1889
 do_iter_write+0x180/0x590 fs/read_write.c:970
 vfs_writev fs/read_write.c:1015 [inline]
 do_writev+0x239/0x490 fs/read_write.c:1058
 __do_sys_writev fs/read_write.c:1131 [inline]
 __se_sys_writev fs/read_write.c:1128 [inline]
 __x64_sys_writev+0x7d/0x90 fs/read_write.c:1128
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a679
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f9e09220c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679
RDX: 000000000000000a RSI: 00000000200007c0 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9e092216d4
R13: 00000000004c8116 R14: 00000000004e43c0 R15: 00000000ffffffff

Allocated by task 12312:
 save_stack mm/kasan/common.c:69 [inline]
 set_track mm/kasan/common.c:77 [inline]
 __kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:510
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524
 __do_kmalloc mm/slab.c:3655 [inline]
 __kmalloc+0x254/0x340 mm/slab.c:3664
 kmalloc_array+0x2f/0x50 include/linux/slab.h:618
 rw_copy_check_uvector+0x96/0x360 fs/read_write.c:792
 import_iovec+0x8c/0x2a0 lib/iov_iter.c:1678
 vfs_writev fs/read_write.c:1012 [inline]
 do_writev+0x156/0x490 fs/read_write.c:1058
 __do_sys_writev fs/read_write.c:1131 [inline]
 __se_sys_writev fs/read_write.c:1128 [inline]
 __x64_sys_writev+0x7d/0x90 fs/read_write.c:1128
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 11727:
 save_stack mm/kasan/common.c:69 [inline]
 set_track mm/kasan/common.c:77 [inline]
 kasan_set_free_info mm/kasan/common.c:332 [inline]
 __kasan_slab_free+0x12a/0x1e0 mm/kasan/common.c:471
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:480
 __cache_free mm/slab.c:3425 [inline]
 kfree+0x115/0x200 mm/slab.c:3756
 security_cred_free+0xcd/0x100 security/security.c:1548
 put_cred_rcu+0xcf/0x360 kernel/cred.c:114
 __rcu_reclaim kernel/rcu/rcu.h:222 [inline]
 rcu_do_batch kernel/rcu/tree.c:2183 [inline]
 rcu_core+0x833/0x10a0 kernel/rcu/tree.c:2408
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2417
 __do_softirq+0x333/0x7c4 arch/x86/include/asm/paravirt.h:762

The buggy address belongs to the object at ffff8880a03de700
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 20 bytes to the right of
 192-byte region [ffff8880a03de700, ffff8880a03de7c0)
The buggy address belongs to the page:
page:ffffea000280f780 refcount:1 mapcount:0 mapping:ffff8880aa400000 index:0x0
raw: 00fffe0000000200 ffffea00026080c8 ffffea00025e2fc8 ffff8880aa400000
raw: 0000000000000000 ffff8880a03de000 0000000100000010 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a03de680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880a03de700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880a03de780: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
                                                 ^
 ffff8880a03de800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880a03de880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
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