==================================================================
BUG: KCSAN: data-race in ext4_handle_inode_extension / filemap_read

write to 0xffff88810d8fc2d0 of 8 bytes by task 11384 on cpu 1:
 i_size_write include/linux/fs.h:872 [inline]
 ext4_update_inode_size fs/ext4/ext4.h:3289 [inline]
 ext4_handle_inode_extension+0x226/0x550 fs/ext4/file.c:331
 ext4_dio_write_iter fs/ext4/file.c:557 [inline]
 ext4_file_write_iter+0xef4/0x10b0 fs/ext4/file.c:661
 call_write_iter include/linux/fs.h:1977 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1319 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88810d8fc2d0 of 8 bytes by task 11387 on cpu 0:
 i_size_read include/linux/fs.h:850 [inline]
 filemap_read+0x1dc/0x7b0 mm/filemap.c:2470
 generic_file_read_iter+0x82/0x410 mm/filemap.c:2609
 ext4_file_read_iter+0x2e0/0x420 fs/ext4/file.c:74
 __kernel_read+0x306/0x580 fs/read_write.c:454
 integrity_kernel_read+0x4c/0x70 security/integrity/iint.c:191
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:484 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:515 [inline]
 ima_calc_file_hash+0x929/0x1310 security/integrity/ima/ima_crypto.c:572
 ima_collect_measurement+0x168/0x310 security/integrity/ima/ima_api.c:252
 process_measurement+0xa88/0x10f0 security/integrity/ima/ima_main.c:330
 ima_file_check+0x75/0xa0 security/integrity/ima/ima_main.c:499
 do_open fs/namei.c:3367 [inline]
 path_openat+0x19c5/0x21b0 fs/namei.c:3498
 do_filp_open+0xbd/0x1d0 fs/namei.c:3525
 do_sys_openat2+0xa3/0x250 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_openat fs/open.c:1219 [inline]
 __se_sys_openat fs/open.c:1214 [inline]
 __x64_sys_openat+0xef/0x110 fs/open.c:1214
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11387 Comm: syz-executor.0 Not tainted 5.12.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================