Re: [PATCH v2] pstore/zone: avoid dereferencing zero sized ptr after init zones

[Kees Cook]

On Fri, 10 Jan 2025 14:57:14 +0200, Eugen Hristev wrote:
> In psz_init_zones, if the requested area has a total_size less than
> record_size, kcalloc will be called with c == 0 and will return
> ZERO_SIZE_PTR.
> Further, this will lead to an oops.
> 
> With this patch, in this scenario, it will look like this :
> [    6.865545] pstore_zone:     total size : 28672 Bytes
> [    6.865547] pstore_zone:     kmsg size : 65536 Bytes
> [    6.865549] pstore_zone:     pmsg size : 0 Bytes
> [    6.865551] pstore_zone:     console size : 0 Bytes
> [    6.865553] pstore_zone:     ftrace size : 0 Bytes
> [    6.872095] pstore_zone: zone dmesg total_size too small
> [    6.878234] pstore_zone: alloc zones failed
> 
> [...]

Applied to for-next/pstore, thanks!

[1/1] pstore/zone: avoid dereferencing zero sized ptr after init zones
      https://git.kernel.org/kees/c/067cdf020329

Take care,

-- 
Kees Cook