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BUG: KASAN: stack-out-of-bounds in iov_iter_revert+0x249/0xa60 lib/iov_iter.c:1100
Read of size 8 at addr ffff8881d1717cd8 by task syz-executor.3/16296

CPU: 1 PID: 16296 Comm: syz-executor.3 Not tainted 5.4.68-syzkaller-00471-g6fa60aa03b21 #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+0x1b0/0x21e lib/dump_stack.c:118
 print_address_description+0x96/0x5d0 mm/kasan/report.c:374
 __kasan_report+0x14b/0x1c0 mm/kasan/report.c:506
 kasan_report+0x27/0x50 mm/kasan/common.c:634
 iov_iter_revert+0x249/0xa60 lib/iov_iter.c:1100
 generic_file_read_iter+0x1d8f/0x20a0 mm/filemap.c:2308
 fuse_cache_read_iter fs/fuse/file.c:1018 [inline]
 fuse_file_read_iter+0x3ec/0x4e0 fs/fuse/file.c:1576
 call_read_iter include/linux/fs.h:1952 [inline]
 new_sync_read fs/read_write.c:414 [inline]
 __vfs_read+0x576/0x6f0 fs/read_write.c:427
 vfs_read+0x166/0x380 fs/read_write.c:461
 ksys_read+0x168/0x2a0 fs/read_write.c:587
 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45dd99
Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f508f480c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000026500 RCX: 000000000045dd99
RDX: 00000000200041e0 RSI: 00000000200021c0 RDI: 0000000000000005
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007fffa1644abf R14: 00007f508f4819c0 R15: 000000000118bf2c

The buggy address belongs to the page:
page:ffffea000745c5c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffffff07450101 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

addr ffff8881d1717cd8 is located in stack of task syz-executor.3/16296 at offset 24 in frame:
 __vfs_read+0x0/0x6f0 fs/read_write.c:39

this frame has 3 objects:
 [32, 48) 'iov.i'
 [64, 112) 'kiocb.i'
 [144, 184) 'iter.i'

Memory state around the buggy address:
 ffff8881d1717b80: f1 f1 f1 f1 00 00 00 00 00 00 00 00 00 f3 f3 f3
 ffff8881d1717c00: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881d1717c80: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 f2 f2
                                                    ^
 ffff8881d1717d00: 00 00 00 00 00 00 f2 f2 f2 f2 00 00 00 00 00 f3
 ffff8881d1717d80: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
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