Re: [PATCH net] crypto: af_alg: Fix merging of written data into spliced pages

[Herbert Xu]

On Tue, Jul 04, 2023 at 04:56:24PM +0100, David Howells wrote:
>     
> af_alg_sendmsg() takes data-to-be-copied that's provided by write(),
> send(), sendmsg() and similar into pages that it allocates and will merge
> new data into the last page in the list, based on the value of ctx->merge.
> 
> Now that af_alg_sendmsg() accepts MSG_SPLICE_PAGES, it adds spliced pages
> directly into the list and then incorrectly appends data to them if there's
> space left because ctx->merge says that it can.  This was cleared by
> af_alg_sendpage(), but that got lost.
> 
> Fix this by skipping the merge if MSG_SPLICE_PAGES is specified and
> clearing ctx->merge after MSG_SPLICE_PAGES has added stuff to the list.
> 
> Fixes: bf63e250c4b1 ("crypto: af_alg: Support MSG_SPLICE_PAGES")
> Reported-by: Ondrej Mosnáček <omosnacek@xxxxxxxxx>
> Link: https://lore.kernel.org/r/CAAUqJDvFuvms55Td1c=XKv6epfRnnP78438nZQ-JKyuCptGBiQ@xxxxxxxxxxxxxx/
> Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
> cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
> cc: Paolo Abeni <pabeni@xxxxxxxxxx>
> cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> cc: Eric Dumazet <edumazet@xxxxxxxxxx>
> cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> cc: linux-crypto@xxxxxxxxxxxxxxx
> cc: netdev@xxxxxxxxxxxxxxx
> ---
>  crypto/af_alg.c |    7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)

Patch appiled.  Thanks.
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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