2018-05-10 12:52:43

by Colin King

Subject: [PATCH][next] net: aquantia: fix unsigned numvecs comparison with less than zero

From: Colin Ian King <[email protected]>

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 <[email protected]>
---
drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c b/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c
index a50e08bb4748..750007513f9d 100644
--- 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 *pdev,
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;

--
2.17.0

2018-05-10 15:37:28

by Igor Russkikh

Subject: Re: [PATCH][next] net: aquantia: fix unsigned numvecs comparison with less than zero

Thanks, Colin!

> 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 <[email protected]>
> ---

Acked-by: Igor Russkikh <[email protected]>

2018-05-10 21:54:43

by David Miller

Subject: Re: [PATCH][next] net: aquantia: fix unsigned numvecs comparison with less than zero

From: Colin King <[email protected]>
Date: Thu, 10 May 2018 13:52:01 +0100

> From: Colin Ian King <[email protected]>
>
> 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 <[email protected]>

This doesn't apply to net-next.

2018-05-11 12:42:30

by Igor Russkikh

Subject: Re: [PATCH][next] net: aquantia: fix unsigned numvecs comparison with less than zero

>> Fixes: a09bd81b5413 ("net: aquantia: Limit number of vectors to actually allocated irqs")
>> Signed-off-by: Colin Ian King <[email protected]>
>
> This doesn't apply to net-next.
>

Colin, believe thats because you should target to net, not net-next.

BR, Igor