From f06d0ca45827a5790d7508de4759aed976933d4d Mon Sep 17 00:00:00 2001 From: Yamin Friedman Date: Tue, 23 Jul 2019 10:22:47 +0300 Subject: linux/dim: Fix overflow in dim calculation While using net_dim, a dim_sample was used without ever initializing the comps value. Added use of DIV_ROUND_DOWN_ULL() to prevent potential overflow, it should not be a problem to save the final result in an int because after the division by epms the value should not be larger than a few thousand. [ 1040.127124] UBSAN: Undefined behaviour in lib/dim/dim.c:78:23 [ 1040.130118] signed integer overflow: [ 1040.131643] 134718714 * 100 cannot be represented in type 'int' Fixes: 398c2b05bbee ("linux/dim: Add completions count to dim_sample") Signed-off-by: Yamin Friedman Signed-off-by: Leon Romanovsky Acked-by: Saeed Mahameed Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bcmsysport.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/ethernet/broadcom/bcmsysport.c') diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c index b9c5cea8db16..9483553ce444 100644 --- a/drivers/net/ethernet/broadcom/bcmsysport.c +++ b/drivers/net/ethernet/broadcom/bcmsysport.c @@ -992,7 +992,7 @@ static int bcm_sysport_poll(struct napi_struct *napi, int budget) { struct bcm_sysport_priv *priv = container_of(napi, struct bcm_sysport_priv, napi); - struct dim_sample dim_sample; + struct dim_sample dim_sample = {}; unsigned int work_done = 0; work_done = bcm_sysport_desc_rx(priv, budget); -- cgit v1.2.3