Commit 44d95cc6 authored May 01, 2020 by Colin Ian King Committed by David S. Miller May 04, 2020

net: stmmac: gmac5+: fix potential integer overflow on 32 bit multiply



The multiplication of cfg->ctr[1] by 1000000000 is performed using a
32 bit multiplication (since cfg->ctr[1] is a u32) and this can lead
to a potential overflow. Fix this by making the constant a ULL to
ensure a 64 bit multiply occurs.

Fixes: 504723af ("net: stmmac: Add basic EST support for GMAC5+")
Addresses-Coverity: ("Unintentional integer overflow")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent a7df4870

drivers/net/ethernet/stmicro/stmmac/dwmac5.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -624,7 +624,7 @@ int dwmac5_est_configure(void __iomem ioaddr, struct stmmac_est cfg,
		total_offset += offset;
		}

		total_ctr = cfg->ctr[0] + cfg->ctr[1] * 1000000000;
		total_ctr = cfg->ctr[0] + cfg->ctr[1] * 1000000000ULL;
		total_ctr += total_offset;

		ctr_low = do_div(total_ctr, 1000000000);

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