2020-09-16 20:52:40

by Alex Dewar

Subject: [PATCH] i40e: Fix use of uninitialized variable

In i40e_clean_rx_irq_zc(), the variable failure is only set when a
condition is met, but then its value is used unconditionally. Fix this.

Addresses-Coverity: 1496986 ("Uninitialized value")
Fixes: 8cbf74149903 ("i40e, xsk: move buffer allocation out of the Rx processing loop")
Signed-off-by: Alex Dewar <[email protected]>
---
drivers/net/ethernet/intel/i40e/i40e_xsk.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
index 6acede0acdca..18c05d23e15e 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c
@@ -364,8 +364,8 @@ int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
napi_gro_receive(&rx_ring->q_vector->napi, skb);
}

- if (cleaned_count >= I40E_RX_BUFFER_WRITE)
- failure = !i40e_alloc_rx_buffers_zc(rx_ring, cleaned_count);
+ failure = (cleaned_count >= I40E_RX_BUFFER_WRITE) &&
+ !i40e_alloc_rx_buffers_zc(rx_ring, cleaned_count);

i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
--
2.28.0

2020-09-17 21:22:18

by Tony Nguyen

Subject: Re: [PATCH] i40e: Fix use of uninitialized variable

On Wed, 2020-09-16 at 21:49 +0100, Alex Dewar wrote:
> In i40e_clean_rx_irq_zc(), the variable failure is only set when a
> condition is met, but then its value is used unconditionally. Fix
> this.
>
> Addresses-Coverity: 1496986 ("Uninitialized value")
> Fixes: 8cbf74149903 ("i40e, xsk: move buffer allocation out of the Rx
> processing loop")
> Signed-off-by: Alex Dewar <[email protected]>

Thanks for the patch Alex, however, Dan Carpenter has already submitted
a patch for the same reported issue:
https://patchwork.ozlabs.org/project/intel-wired-lan/patch/20200916143228.GA764370@mwanda/

Thanks,
Tony