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Florian Westphal
ddbd8be689
On some platforms there is a padding hole in the nft_verdict
structure, between the verdict code and the chain pointer.
On element insertion, if the new element clashes with an existing one and
NLM_F_EXCL flag isn't set, we want to ignore the -EEXIST error as long as
the data associated with duplicated element is the same as the existing
one. The data equality check uses memcmp.
For normal data (NFT_DATA_VALUE) this works fine, but for NFT_DATA_VERDICT
padding area leads to spurious failure even if the verdict data is the
same.
This then makes the insertion fail with 'already exists' error, even
though the new "key : data" matches an existing entry and userspace
told the kernel that it doesn't want to receive an error indication.
Fixes: c016c7e45d ("netfilter: nf_tables: honor NLM_F_EXCL flag in set element insertion")
Signed-off-by: Florian Westphal <fw@strlen.de>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
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Please read the Documentation/process/changes.rst file, as it contains the
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the problems which may result by upgrading your kernel.