releases/4.16.17/net-aquantia-fix-unsigned-numvecs-comparison-with-less-than-zero.patch

From 58d813afbe89658a5972747460a5fe19dec4dbcb Mon Sep 17 00:00:00 2001
From: Colin Ian King <colin.king@canonical.com>
Date: Thu, 7 Jun 2018 17:54:37 -0400
Subject: net: aquantia: fix unsigned numvecs comparison with less than zero

From: Colin Ian King <colin.king@canonical.com>

commit 58d813afbe89658a5972747460a5fe19dec4dbcb upstream.

This was originally mistakenly submitted to net-next. Resubmitting to net.

The comparison of numvecs < 0 is always false because numvecs is a u32
and hence the error return from a failed call to pci_alloc_irq_vectores
is never detected.  Fix this by using the signed int ret to handle the
error return and assign numvecs to err.

Detected by CoverityScan, CID#1468650 ("Unsigned compared against 0")

Fixes: a09bd81b5413 ("net: aquantia: Limit number of vectors to actually allocated irqs")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Igor Russkikh <igor.russkikh@aquantia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c |   11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

--- a/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c
@@ -267,14 +267,13 @@ static int aq_pci_probe(struct pci_dev *
 	numvecs = min(numvecs, num_online_cpus());
 	/*enable interrupts */
 #if !AQ_CFG_FORCE_LEGACY_INT
-	numvecs = pci_alloc_irq_vectors(self->pdev, 1, numvecs,
-					PCI_IRQ_MSIX | PCI_IRQ_MSI |
-					PCI_IRQ_LEGACY);
+	err = pci_alloc_irq_vectors(self->pdev, 1, numvecs,
+				    PCI_IRQ_MSIX | PCI_IRQ_MSI |
+				    PCI_IRQ_LEGACY);
 
-	if (numvecs < 0) {
-		err = numvecs;
+	if (err < 0)
 		goto err_hwinit;
-	}
+	numvecs = err;
 #endif
 	self->irqvecs = numvecs;