syzbot

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BUG: KCSAN: data-race in block_page_mkwrite / generic_write_end

write to 0xffff888106386a88 of 8 bytes by task 9893 on cpu 0:
 i_size_write include/linux/fs.h:901 [inline]
 generic_write_end+0x9f/0x240 fs/buffer.c:2304
 ext4_da_write_end+0x49e/0x700 fs/ext4/inode.c:2988
 generic_perform_write+0x26d/0x410 mm/filemap.c:3934
 ext4_buffered_write_iter+0x1f6/0x370 fs/ext4/file.c:299
 ext4_file_write_iter+0x283/0x1230
 call_write_iter include/linux/fs.h:1877 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x4ab/0x7d0 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 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

read to 0xffff888106386a88 of 8 bytes by task 9890 on cpu 1:
 i_size_read include/linux/fs.h:879 [inline]
 block_page_mkwrite+0xd3/0x400 fs/buffer.c:2638
 ext4_page_mkwrite+0x782/0xba0 fs/ext4/inode.c:6061
 do_page_mkwrite mm/memory.c:2942 [inline]
 wp_page_shared mm/memory.c:3294 [inline]
 do_wp_page+0x7f4/0x1fd0 mm/memory.c:3376
 handle_pte_fault mm/memory.c:4955 [inline]
 __handle_mm_fault mm/memory.c:5079 [inline]
 handle_mm_fault+0x589/0x2c10 mm/memory.c:5233
 do_user_addr_fault arch/x86/mm/fault.c:1392 [inline]
 handle_page_fault arch/x86/mm/fault.c:1486 [inline]
 exc_page_fault+0x24d/0x650 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
 __put_user_nocheck_4+0xb/0x20 arch/x86/lib/putuser.S:99
 ____sys_recvmsg+0x20f/0x310 net/socket.c:2726
 ___sys_recvmsg net/socket.c:2755 [inline]
 do_recvmmsg+0x2eb/0x720 net/socket.c:2849
 __sys_recvmmsg net/socket.c:2928 [inline]
 __do_sys_recvmmsg net/socket.c:2951 [inline]
 __se_sys_recvmmsg net/socket.c:2944 [inline]
 __x64_sys_recvmmsg+0xe2/0x160 net/socket.c:2944
 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

value changed: 0x0000000000eab000 -> 0x0000000000eac000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9890 Comm: syz-executor.3 Not tainted 6.5.0-rc5-syzkaller-00182-g25aa0bebba72 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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