Date:   Sun, 29 Jan 2023 23:47:20 +0100
From:   Vasily Gorbik <gor@linux.ibm.com>
To:     Heiko Carstens <hca@linux.ibm.com>,
        Alexander Egorenkov <egorenar@linux.ibm.com>
Cc:     Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Nick Terrell <terrelln@fb.com>, linux-s390@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org
Subject: [PATCH 0/1] s390: fix initrd corruption in decompressor with new
 zstd version
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The new version of zstd library integrated in the kernel since v6.2-rc1
https://lore.kernel.org/all/20221024202606.404049-1-nickrterrell@gmail.com/
contains commit
https://github.com/facebook/zstd/commit/6a7ede3dfccb
which introduces a side effect for historical usage of __decompress() function,
i.e. not specifying "out_len" parameter and expecting that no writes beyond
uncompressed kernel image are performed. More details are in follow up fix.

From architectures which claim HAVE_KERNEL_ZSTD, s390 and MIPS use
__decompress() without specifying "out_len". On s390 this leads to
initrd corruption.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2003348

I haven't looked in details for MIPS but I've added Thomas as the
maintainer and MIPS list in Cc.

The follow up fix addresses that for s390.

Vasily Gorbik (1):
  s390/decompressor: specify __decompress() buf len to avoid overflow

 arch/s390/boot/decompressor.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

-- 
2.38.1