[PATCH 5.11 066/210] i40e: Fix sparse errors in i40e_txrx.c

Greg Kroah-Hartman
2021-04-12T09:31:05Z

From: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>

commit 12738ac4754ec92a6a45bf3677d8da780a1412b3 upstream.

Remove error handling through pointers. Instead use plain int
to return value from i40e_run_xdp(...).

Previously:
- sparse errors were produced during compilation:
i40e_txrx.c:2338 i40e_run_xdp() error: (-2147483647) too low for ERR_PTR
i40e_txrx.c:2558 i40e_clean_rx_irq() error: 'skb' dereferencing possible ERR_PTR()

- sk_buff* was used to return value, but it has never had valid
pointer to sk_buff. Returned value was always int handled as
a pointer.

Fixes: 0c8493d90b6b ("i40e: add XDP support for pass and drop actions")
Fixes: 2e6893123830 ("i40e: split XDP_TX tail and XDP_REDIRECT map flushing")
Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Tested-by: Dave Switzer <david.switzer@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/intel/i40e/i40e_txrx.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -2198,8 +2198,7 @@ int i40e_xmit_xdp_tx_ring(struct xdp_buf
* @rx_ring: Rx ring being processed
* @xdp: XDP buffer containing the frame
**/
-static struct sk_buff *i40e_run_xdp(struct i40e_ring *rx_ring,
- struct xdp_buff *xdp)
+static int i40e_run_xdp(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
{
int err, result = I40E_XDP_PASS;
struct i40e_ring *xdp_ring;
@@ -2238,7 +2237,7 @@ static struct sk_buff *i40e_run_xdp(stru
}
xdp_out:
rcu_read_unlock();
- return ERR_PTR(-result);
+ return result;
}

/**
@@ -2350,6 +2349,7 @@ static int i40e_clean_rx_irq(struct i40e
unsigned int xdp_xmit = 0;
bool failure = false;
struct xdp_buff xdp;
+ int xdp_res = 0;

#if (PAGE_SIZE < 8192)
xdp.frame_sz = i40e_rx_frame_truesize(rx_ring, 0);
@@ -2416,12 +2416,10 @@ static int i40e_clean_rx_irq(struct i40e
/* At larger PAGE_SIZE, frame_sz depend on len size */
xdp.frame_sz = i40e_rx_frame_truesize(rx_ring, size);
#endif
- skb = i40e_run_xdp(rx_ring, &xdp);
+ xdp_res = i40e_run_xdp(rx_ring, &xdp);
}

- if (IS_ERR(skb)) {
- unsigned int xdp_res = -PTR_ERR(skb);
-
+ if (xdp_res) {
if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
xdp_xmit |= xdp_res;
i40e_rx_buffer_flip(rx_ring, rx_buffer, size);