loop5: detected capacity change from 0 to 2048 EXT4-fs (loop5): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. ================================================================== BUG: KCSAN: data-race in filemap_read / filemap_read read to 0xffff8881425aa090 of 8 bytes by task 1394 on cpu 0: filemap_read+0x89/0x680 mm/filemap.c:2628 generic_file_read_iter+0x78/0x330 mm/filemap.c:2831 ext4_file_read_iter+0x1d8/0x2a0 call_read_iter include/linux/fs.h:1950 [inline] copy_splice_read+0x26b/0x4b0 fs/splice.c:364 vfs_splice_read fs/splice.c:992 [inline] splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069 do_splice_direct+0x10d/0x190 fs/splice.c:1194 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64 fs/read_write.c:1308 [inline] __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308 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 write to 0xffff8881425aa090 of 8 bytes by task 1393 on cpu 1: filemap_read+0x605/0x680 mm/filemap.c:2721 generic_file_read_iter+0x78/0x330 mm/filemap.c:2831 ext4_file_read_iter+0x1d8/0x2a0 call_read_iter include/linux/fs.h:1950 [inline] copy_splice_read+0x26b/0x4b0 fs/splice.c:364 vfs_splice_read fs/splice.c:992 [inline] splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069 do_splice_direct+0x10d/0x190 fs/splice.c:1194 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64 fs/read_write.c:1308 [inline] __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308 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: 0x00000000000005f0 -> 0x00000000000005f4 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 1393 Comm: syz-executor.5 Not tainted 6.6.0-rc6-syzkaller-00207-gc8045b4a33a5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 ==================================================================