From: Ke Li Date: Thu, 22 Oct 2020 06:41:46 +0000 (-0400) Subject: net: Properly typecast int values to set sk_max_pacing_rate X-Git-Tag: v5.8.17~589 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f6bb7b012676fa37d40a28c9ea0463ec951a5599;p=thirdparty%2Fkernel%2Fstable.git net: Properly typecast int values to set sk_max_pacing_rate [ Upstream commit 700465fd338fe5df08a1b2e27fa16981f562547f ] 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: 76a9ebe811fb ("net: extend sk_pacing_rate to unsigned long") Signed-off-by: Ji Li Signed-off-by: Ke Li Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/20201022064146.79873-1-keli@akamai.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/core/filter.c b/net/core/filter.c index 0261531d4fda6..3e4de9e461bd0 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -4323,7 +4323,8 @@ static int _bpf_setsockopt(struct sock *sk, int level, int optname, cmpxchg(&sk->sk_pacing_status, SK_PACING_NONE, SK_PACING_NEEDED); - sk->sk_max_pacing_rate = (val == ~0U) ? ~0UL : val; + sk->sk_max_pacing_rate = (val == ~0U) ? + ~0UL : (unsigned int)val; sk->sk_pacing_rate = min(sk->sk_pacing_rate, sk->sk_max_pacing_rate); break; diff --git a/net/core/sock.c b/net/core/sock.c index a562b70f69d6d..25968369fe7f6 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1184,7 +1184,7 @@ set_sndbuf: case SO_MAX_PACING_RATE: { - unsigned long ulval = (val == ~0U) ? ~0UL : val; + unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val; if (sizeof(ulval) != sizeof(val) && optlen >= sizeof(ulval) &&