================================================================== BUG: KCSAN: data-race in mark_buffer_dirty_inode / mark_buffer_dirty_inode write to 0xffff888106d50468 of 8 bytes by task 21477 on cpu 0: mark_buffer_dirty_inode+0x18d/0x1c0 fs/buffer.c:684 fat_mirror_bhs+0x241/0x330 fs/fat/fatent.c:398 fat_alloc_clusters+0x994/0xa80 fs/fat/fatent.c:543 fat_add_cluster fs/fat/inode.c:108 [inline] __fat_get_block fs/fat/inode.c:155 [inline] fat_get_block+0x25c/0x5e0 fs/fat/inode.c:190 __block_write_begin_int+0x417/0xfa0 fs/buffer.c:2128 __block_write_begin fs/buffer.c:2177 [inline] block_write_begin+0x7b/0x170 fs/buffer.c:2236 cont_write_begin+0x486/0x6b0 fs/buffer.c:2590 fat_write_begin+0x61/0xf0 fs/fat/inode.c:230 cont_expand_zero fs/buffer.c:2517 [inline] cont_write_begin+0x186/0x6b0 fs/buffer.c:2580 fat_write_begin+0x61/0xf0 fs/fat/inode.c:230 generic_cont_expand_simple+0xaa/0x150 fs/buffer.c:2481 fat_cont_expand+0x3a/0x160 fs/fat/file.c:223 fat_setattr+0x2aa/0x840 fs/fat/file.c:513 notify_change+0x814/0x8a0 fs/attr.c:497 do_truncate fs/open.c:65 [inline] do_ftruncate+0x3e1/0x470 fs/open.c:181 do_sys_ftruncate fs/open.c:199 [inline] __do_sys_ftruncate fs/open.c:207 [inline] __se_sys_ftruncate fs/open.c:205 [inline] __x64_sys_ftruncate+0x6a/0xc0 fs/open.c:205 x64_sys_call+0x1f60/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:78 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff888106d50468 of 8 bytes by task 21479 on cpu 1: mark_buffer_dirty_inode+0x96/0x1c0 fs/buffer.c:680 fat_mirror_bhs+0x241/0x330 fs/fat/fatent.c:398 fat_alloc_clusters+0x994/0xa80 fs/fat/fatent.c:543 fat_add_cluster fs/fat/inode.c:108 [inline] __fat_get_block fs/fat/inode.c:155 [inline] fat_get_block+0x25c/0x5e0 fs/fat/inode.c:190 __block_write_begin_int+0x417/0xfa0 fs/buffer.c:2128 __block_write_begin fs/buffer.c:2177 [inline] block_write_begin+0x7b/0x170 fs/buffer.c:2236 cont_write_begin+0x486/0x6b0 fs/buffer.c:2590 fat_write_begin+0x61/0xf0 fs/fat/inode.c:230 cont_expand_zero fs/buffer.c:2517 [inline] cont_write_begin+0x186/0x6b0 fs/buffer.c:2580 fat_write_begin+0x61/0xf0 fs/fat/inode.c:230 generic_cont_expand_simple+0xaa/0x150 fs/buffer.c:2481 fat_cont_expand+0x3a/0x160 fs/fat/file.c:223 fat_setattr+0x2aa/0x840 fs/fat/file.c:513 notify_change+0x814/0x8a0 fs/attr.c:497 do_truncate fs/open.c:65 [inline] do_ftruncate+0x3e1/0x470 fs/open.c:181 do_sys_ftruncate fs/open.c:199 [inline] __do_sys_ftruncate fs/open.c:207 [inline] __se_sys_ftruncate fs/open.c:205 [inline] __x64_sys_ftruncate+0x6a/0xc0 fs/open.c:205 x64_sys_call+0x1f60/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:78 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x0000000000000000 -> 0xffff888106e71a50 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 21479 Comm: syz-executor.3 Tainted: G W 6.10.0-rc4-syzkaller-00052-ge5b3efbe1ab1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 ==================================================================