EXT4-fs (loop5): bad geometry: block count 515 exceeds size of device (512 blocks)
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BUG: KCSAN: data-race in data_push_tail / number

write to 0xffffffff86dbb757 of 1 bytes by task 28392 on cpu 0:
 number+0x846/0xb60 lib/vsprintf.c:556
 vsnprintf+0xb6d/0xed0 lib/vsprintf.c:2861
 vscnprintf+0x29/0x80 lib/vsprintf.c:2898
 printk_sprint kernel/printk/printk.c:2076 [inline]
 vprintk_store+0x638/0xbb0 kernel/printk/printk.c:2186
 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2229
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2256
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x97 kernel/printk/printk.c:2266
 set_capacity_and_notify+0x170/0x1d0 block/genhd.c:89
 loop_set_size drivers/block/loop.c:232 [inline]
 loop_configure+0xd53/0xf50 drivers/block/loop.c:1060
 lo_ioctl+0x633/0x1260
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:588
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff86dbb750 of 8 bytes by task 28383 on cpu 1:
 data_make_reusable kernel/printk/printk_ringbuffer.c:587 [inline]
 data_push_tail+0x138/0x470 kernel/printk/printk_ringbuffer.c:672
 data_alloc+0xbc/0x2b0 kernel/printk/printk_ringbuffer.c:1043
 prb_reserve+0x920/0xbf0 kernel/printk/printk_ringbuffer.c:1549
 vprintk_store+0x560/0xbb0 kernel/printk/printk.c:2176
 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2229
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2256
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x97 kernel/printk/printk.c:2266
 __ext4_msg+0x16d/0x180 fs/ext4/super.c:944
 __ext4_fill_super+0x2315/0x59b0
 ext4_fill_super+0x10b/0x2f0 fs/ext4/super.c:5554
 get_tree_bdev+0x2c2/0x3d0 fs/super.c:1292
 vfs_get_tree+0x4a/0x1a0 fs/super.c:1497
 do_new_mount fs/namespace.c:3024 [inline]
 path_mount+0x11cf/0x1c40 fs/namespace.c:3354
 do_mount fs/namespace.c:3367 [inline]
 __do_sys_mount fs/namespace.c:3575 [inline]
 __se_sys_mount+0x24b/0x2f0 fs/namespace.c:3552
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3552
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000100005e53 -> 0x00206d6f72662065

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 28383 Comm: syz-executor.5 Not tainted 5.17.0-rc8-syzkaller-00003-g56e337f2cf13-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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