net: Properly typecast int values to set sk_max_pacing_rate
In setsockopt(SO_MAX_PACING_RATE) on 64bit systems, sk_max_pacing_rate, after extended from 'u32' to 'unsigned long', takes unintentionally hiked value whenever assigned from an 'int' value with MSB=1, due to binary sign extension in promoting s32 to u64, e.g. 0x80000000 becomes 0xFFFFFFFF80000000. Thus inflated sk_max_pacing_rate causes subsequent getsockopt to return ~0U unexpectedly. It may also result in increased pacing rate. Fix by explicitly casting the 'int' value to 'unsigned int' before assigning it to sk_max_pacing_rate, for zero extension to happen. Fixes: 76a9ebe8 ("net: extend sk_pacing_rate to unsigned long") Signed-off-by: Ji Li <jli@akamai.com> Signed-off-by: Ke Li <keli@akamai.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20201022064146.79873-1-keli@akamai.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>
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