net: mvneta: Prevent out of bounds read in mvneta_config_rss()

[ Upstream commit e8b4fc13900b8e8be48debffd0dfd391772501f7 ]

The pp->indir[0] value comes from the user.  It is passed to:

	if (cpu_online(pp->rxq_def))

inside the mvneta_percpu_elect() function.  It needs bounds checkeding
to ensure that it is not beyond the end of the cpu bitmap.

Fixes: cad5d847a093 ("net: mvneta: Fix the CPU choice in mvneta_percpu_elect")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index ccacdcfb593216d7b924d92597cb4104078bdfc4..86eb258ed8112beb8cde28ec7eee7fa5a440a46a 100644 (file)
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -3761,6 +3761,9 @@ static int  mvneta_config_rss(struct mvneta_port *pp)
                napi_disable(&pcpu_port->napi);
        }
 
+       if (pp->indir[0] >= nr_cpu_ids)
+               return -EINVAL;
+
        pp->rxq_def = pp->indir[0];
 
        /* Update unicast mapping */