[syzbot] [block?] WARNING: zero-size vmalloc in disksize_store

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    73ae59e97596 Merge tag 'erofs-for-7.3-rc1-2' of git://git...
git tree:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master
console output: https://syzkaller.appspot.com/x/log.txt?x=11d5d525580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c35e49327a11721f
dashboard link: https://syzkaller.appspot.com/bug?extid=fb23651a7efbea8868ed
compiler:       aarch64-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=175514c9580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=123b1005580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/fa3fbcfdac58/non_bootable_disk-73ae59e9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9a72e0bdbe94/vmlinux-73ae59e9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d050a726f316/Image-73ae59e9.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fb23651a7efbea8868ed@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: mm/vmalloc.c:4038 at __vmalloc_node_range_noprof+0x798/0x8ec mm/vmalloc.c:4038, CPU#0: syz.2.17/3661
Modules linked in:
CPU: 0 UID: 0 PID: 3661 Comm: syz.2.17 Tainted: G        W           syzkaller #0 PREEMPT 
Tainted: [W]=WARN
Hardware name: linux,dummy-virt (DT)
pstate: 01402009 (nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : __vmalloc_node_range_noprof+0x798/0x8ec mm/vmalloc.c:4038
lr : __vmalloc_node_noprof mm/vmalloc.c:4166 [inline]
lr : vzalloc_noprof+0x94/0xa4 mm/vmalloc.c:4244
sp : ffff800089a53b20
x29: ffff800089a53b30 x28: fcf00000046e0000 x27: 00000000ffffffff
x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000
x23: 0000000000000000 x22: f3f00000057d3140 x21: 0000000000000012
x20: 0000000000000000 x19: f3f00000057d3100 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000020000000
x14: 0000000000000000 x13: 0000000000000000 x12: 0000000080000000
x11: 0000000000000000 x10: 0fffffffffffffff x9 : 0000000000000010
x8 : 00000000ffffffbf x7 : 00000000ffffffff x6 : 0000000000000000
x5 : 00e8000000000403 x4 : 0000000000000dc0 x3 : ffffc1ffbf800000
x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 __vmalloc_node_range_noprof+0x798/0x8ec mm/vmalloc.c:4038 (P)
 __vmalloc_node_noprof mm/vmalloc.c:4166 [inline]
 vzalloc_noprof+0x94/0xa4 mm/vmalloc.c:4244
 zram_meta_alloc drivers/block/zram/zram_drv.c:1982 [inline]
 disksize_store+0x64/0x1b0 drivers/block/zram/zram_drv.c:2872
 dev_attr_store+0x18/0x2c drivers/base/core.c:2509
 sysfs_kf_write+0x7c/0x98 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x138/0x200 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x244/0x36c fs/read_write.c:687
 ksys_write+0x70/0x108 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __arm64_sys_write+0x18/0x24 fs/read_write.c:747
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x54/0x10c arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x1c/0x34 arch/arm64/kernel/syscall.c:140
 el0_svc+0x38/0x1fc arch/arm64/kernel/entry-common.c:758
 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:777
 el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:590
---[ end trace 0000000000000000 ]---


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