================================================================== BUG: KCSAN: data-race in data_push_tail / number write to 0xffffffff8415a588 of 1 bytes by task 16352 on cpu 0: number+0x72b/0xb50 lib/vsprintf.c:543 vsnprintf+0xb6d/0xed0 lib/vsprintf.c:2863 va_format lib/vsprintf.c:1694 [inline] pointer+0x47b/0x820 lib/vsprintf.c:2427 vsnprintf+0x8a1/0xed0 lib/vsprintf.c:2801 vscnprintf+0x29/0x80 lib/vsprintf.c:2900 printk_sprint kernel/printk/printk.c:2012 [inline] vprintk_store+0x4c1/0x9c0 kernel/printk/printk.c:2115 vprintk_emit+0xca/0x3d0 kernel/printk/printk.c:2157 vprintk_default+0x22/0x30 kernel/printk/printk.c:2185 vprintk+0x15a/0x170 kernel/printk/printk_safe.c:392 printk+0x62/0x87 kernel/printk/printk.c:2216 fat_msg+0x80/0xaf fs/fat/misc.c:56 fat_fill_super+0x23bc/0x2a80 fs/fat/inode.c:1740 vfat_fill_super+0x2c/0x40 fs/fat/namei_vfat.c:1051 mount_bdev+0x1e8/0x290 fs/super.c:1368 vfat_mount+0x2d/0x40 fs/fat/namei_vfat.c:1058 legacy_get_tree+0x70/0xc0 fs/fs_context.c:610 vfs_get_tree+0x4a/0x1a0 fs/super.c:1498 do_new_mount fs/namespace.c:2919 [inline] path_mount+0x11d4/0x1ce0 fs/namespace.c:3249 do_mount fs/namespace.c:3262 [inline] __do_sys_mount fs/namespace.c:3470 [inline] __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3447 __x64_sys_mount+0x63/0x70 fs/namespace.c:3447 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffffffff8415a588 of 8 bytes by task 16349 on cpu 1: data_make_reusable kernel/printk/printk_ringbuffer.c:587 [inline] data_push_tail+0x125/0x460 kernel/printk/printk_ringbuffer.c:672 data_alloc+0xbc/0x2b0 kernel/printk/printk_ringbuffer.c:1043 prb_reserve+0x8f0/0xbc0 kernel/printk/printk_ringbuffer.c:1549 vprintk_store+0x3e9/0x9c0 kernel/printk/printk.c:2105 vprintk_emit+0xca/0x3d0 kernel/printk/printk.c:2157 vprintk_default+0x22/0x30 kernel/printk/printk.c:2185 vprintk+0x15a/0x170 kernel/printk/printk_safe.c:392 printk+0x62/0x87 kernel/printk/printk.c:2216 fat_msg+0x80/0xaf fs/fat/misc.c:56 fat_fill_super+0x23bc/0x2a80 fs/fat/inode.c:1740 vfat_fill_super+0x2c/0x40 fs/fat/namei_vfat.c:1051 mount_bdev+0x1e8/0x290 fs/super.c:1368 vfat_mount+0x2d/0x40 fs/fat/namei_vfat.c:1058 legacy_get_tree+0x70/0xc0 fs/fs_context.c:610 vfs_get_tree+0x4a/0x1a0 fs/super.c:1498 do_new_mount fs/namespace.c:2919 [inline] path_mount+0x11d4/0x1ce0 fs/namespace.c:3249 do_mount fs/namespace.c:3262 [inline] __do_sys_mount fs/namespace.c:3470 [inline] __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3447 __x64_sys_mount+0x63/0x70 fs/namespace.c:3447 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000001000055ea -> 0x726f746365732820 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 16349 Comm: syz-executor.1 Not tainted 5.14.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================