* [PATCH] [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
@ 2021-09-27 10:02 ` Arnd Bergmann
0 siblings, 0 replies; 8+ messages in thread
From: Arnd Bergmann @ 2021-09-27 10:02 UTC (permalink / raw)
To: Giuseppe Cavallaro, Alexandre Torgue, Jose Abreu,
David S. Miller, Jakub Kicinski, Voon Weifeng, Ong Boon Leong
Cc: Arnd Bergmann, kernel test robot, Dan Carpenter, netdev,
linux-arm-kernel, linux-kernel
From: Arnd Bergmann <arnd@arndb.de>
gcc-10 and later warn about a theoretical array overrun when
accessing priv->int_name_rx_irq[i] with an out of bounds value
of 'i':
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c: In function 'stmmac_request_irq_multi_msi':
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3528:17: error: 'snprintf' argument 4 may overlap destination object 'dev' [-Werror=restrict]
3528 | snprintf(int_name, int_name_len, "%s:%s-%d", dev->name, "tx", i);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3404:60: note: destination object referenced by 'restrict'-qualified argument 1 was declared here
3404 | static int stmmac_request_irq_multi_msi(struct net_device *dev)
| ~~~~~~~~~~~~~~~~~~~^~~
The warning is a bit strange since it's not actually about the array
bounds but rather about possible string operations with overlapping
arguments, but it's not technically wrong.
Avoid the warning by adding an extra bounds check.
Fixes: 8532f613bc78 ("net: stmmac: introduce MSI Interrupt routines for mac, safety, RX & TX")
Link: https://lore.kernel.org/all/20210421134743.3260921-1-arnd@kernel.org/
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 553c4403258a..640c0ffdff3d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3502,6 +3502,8 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)
/* Request Rx MSI irq */
for (i = 0; i < priv->plat->rx_queues_to_use; i++) {
+ if (i > MTL_MAX_RX_QUEUES)
+ break;
if (priv->rx_irq[i] == 0)
continue;
@@ -3525,6 +3527,8 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)
/* Request Tx MSI irq */
for (i = 0; i < priv->plat->tx_queues_to_use; i++) {
+ if (i > MTL_MAX_TX_QUEUES)
+ break;
if (priv->tx_irq[i] == 0)
continue;
--
2.29.2
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^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH] [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
2021-09-27 10:02 ` Arnd Bergmann
@ 2021-09-27 13:00 ` patchwork-bot+netdevbpf
-1 siblings, 0 replies; 8+ messages in thread
From: patchwork-bot+netdevbpf @ 2021-09-27 13:00 UTC (permalink / raw)
To: Arnd Bergmann
Cc: peppe.cavallaro, alexandre.torgue, joabreu, davem, kuba,
weifeng.voon, boon.leong.ong, arnd, lkp, dan.carpenter, netdev,
linux-arm-kernel, linux-kernel
Hello:
This patch was applied to netdev/net-next.git (refs/heads/master):
On Mon, 27 Sep 2021 12:02:44 +0200 you wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>
> gcc-10 and later warn about a theoretical array overrun when
> accessing priv->int_name_rx_irq[i] with an out of bounds value
> of 'i':
>
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c: In function 'stmmac_request_irq_multi_msi':
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3528:17: error: 'snprintf' argument 4 may overlap destination object 'dev' [-Werror=restrict]
> 3528 | snprintf(int_name, int_name_len, "%s:%s-%d", dev->name, "tx", i);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3404:60: note: destination object referenced by 'restrict'-qualified argument 1 was declared here
> 3404 | static int stmmac_request_irq_multi_msi(struct net_device *dev)
> | ~~~~~~~~~~~~~~~~~~~^~~
>
> [...]
Here is the summary with links:
- [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
https://git.kernel.org/netdev/net-next/c/3e0d5699a975
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
@ 2021-09-27 13:00 ` patchwork-bot+netdevbpf
0 siblings, 0 replies; 8+ messages in thread
From: patchwork-bot+netdevbpf @ 2021-09-27 13:00 UTC (permalink / raw)
To: Arnd Bergmann
Cc: peppe.cavallaro, alexandre.torgue, joabreu, davem, kuba,
weifeng.voon, boon.leong.ong, arnd, lkp, dan.carpenter, netdev,
linux-arm-kernel, linux-kernel
Hello:
This patch was applied to netdev/net-next.git (refs/heads/master):
On Mon, 27 Sep 2021 12:02:44 +0200 you wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>
> gcc-10 and later warn about a theoretical array overrun when
> accessing priv->int_name_rx_irq[i] with an out of bounds value
> of 'i':
>
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c: In function 'stmmac_request_irq_multi_msi':
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3528:17: error: 'snprintf' argument 4 may overlap destination object 'dev' [-Werror=restrict]
> 3528 | snprintf(int_name, int_name_len, "%s:%s-%d", dev->name, "tx", i);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3404:60: note: destination object referenced by 'restrict'-qualified argument 1 was declared here
> 3404 | static int stmmac_request_irq_multi_msi(struct net_device *dev)
> | ~~~~~~~~~~~~~~~~~~~^~~
>
> [...]
Here is the summary with links:
- [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
https://git.kernel.org/netdev/net-next/c/3e0d5699a975
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
2021-09-27 10:02 ` Arnd Bergmann
@ 2021-09-27 13:26 ` Russell King (Oracle)
-1 siblings, 0 replies; 8+ messages in thread
From: Russell King (Oracle) @ 2021-09-27 13:26 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Giuseppe Cavallaro, Alexandre Torgue, Jose Abreu,
David S. Miller, Jakub Kicinski, Voon Weifeng, Ong Boon Leong,
Arnd Bergmann, kernel test robot, Dan Carpenter, netdev,
linux-arm-kernel, linux-kernel
On Mon, Sep 27, 2021 at 12:02:44PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>
> gcc-10 and later warn about a theoretical array overrun when
> accessing priv->int_name_rx_irq[i] with an out of bounds value
> of 'i':
>
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c: In function 'stmmac_request_irq_multi_msi':
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3528:17: error: 'snprintf' argument 4 may overlap destination object 'dev' [-Werror=restrict]
> 3528 | snprintf(int_name, int_name_len, "%s:%s-%d", dev->name, "tx", i);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3404:60: note: destination object referenced by 'restrict'-qualified argument 1 was declared here
> 3404 | static int stmmac_request_irq_multi_msi(struct net_device *dev)
> | ~~~~~~~~~~~~~~~~~~~^~~
>
> The warning is a bit strange since it's not actually about the array
> bounds but rather about possible string operations with overlapping
> arguments, but it's not technically wrong.
>
> Avoid the warning by adding an extra bounds check.
>
> Fixes: 8532f613bc78 ("net: stmmac: introduce MSI Interrupt routines for mac, safety, RX & TX")
> Link: https://lore.kernel.org/all/20210421134743.3260921-1-arnd@kernel.org/
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 553c4403258a..640c0ffdff3d 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -3502,6 +3502,8 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)
>
> /* Request Rx MSI irq */
> for (i = 0; i < priv->plat->rx_queues_to_use; i++) {
> + if (i > MTL_MAX_RX_QUEUES)
> + break;
> if (priv->rx_irq[i] == 0)
> continue;
This looks rather weird. rx_irq[] is defined as:
int rx_irq[MTL_MAX_RX_QUEUES];
If "i" were to become MTL_MAX_RX_QUEUES, then the above code overlows
the array.
So while this may stop gcc-10 complaining, I'd argue that making the
new test ">=" rather than ">" would have also made it look correct.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
@ 2021-09-27 13:26 ` Russell King (Oracle)
0 siblings, 0 replies; 8+ messages in thread
From: Russell King (Oracle) @ 2021-09-27 13:26 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Giuseppe Cavallaro, Alexandre Torgue, Jose Abreu,
David S. Miller, Jakub Kicinski, Voon Weifeng, Ong Boon Leong,
Arnd Bergmann, kernel test robot, Dan Carpenter, netdev,
linux-arm-kernel, linux-kernel
On Mon, Sep 27, 2021 at 12:02:44PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>
> gcc-10 and later warn about a theoretical array overrun when
> accessing priv->int_name_rx_irq[i] with an out of bounds value
> of 'i':
>
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c: In function 'stmmac_request_irq_multi_msi':
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3528:17: error: 'snprintf' argument 4 may overlap destination object 'dev' [-Werror=restrict]
> 3528 | snprintf(int_name, int_name_len, "%s:%s-%d", dev->name, "tx", i);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:3404:60: note: destination object referenced by 'restrict'-qualified argument 1 was declared here
> 3404 | static int stmmac_request_irq_multi_msi(struct net_device *dev)
> | ~~~~~~~~~~~~~~~~~~~^~~
>
> The warning is a bit strange since it's not actually about the array
> bounds but rather about possible string operations with overlapping
> arguments, but it's not technically wrong.
>
> Avoid the warning by adding an extra bounds check.
>
> Fixes: 8532f613bc78 ("net: stmmac: introduce MSI Interrupt routines for mac, safety, RX & TX")
> Link: https://lore.kernel.org/all/20210421134743.3260921-1-arnd@kernel.org/
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 553c4403258a..640c0ffdff3d 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -3502,6 +3502,8 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)
>
> /* Request Rx MSI irq */
> for (i = 0; i < priv->plat->rx_queues_to_use; i++) {
> + if (i > MTL_MAX_RX_QUEUES)
> + break;
> if (priv->rx_irq[i] == 0)
> continue;
This looks rather weird. rx_irq[] is defined as:
int rx_irq[MTL_MAX_RX_QUEUES];
If "i" were to become MTL_MAX_RX_QUEUES, then the above code overlows
the array.
So while this may stop gcc-10 complaining, I'd argue that making the
new test ">=" rather than ">" would have also made it look correct.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
2021-09-27 13:26 ` Russell King (Oracle)
@ 2021-09-27 13:59 ` Arnd Bergmann
-1 siblings, 0 replies; 8+ messages in thread
From: Arnd Bergmann @ 2021-09-27 13:59 UTC (permalink / raw)
To: Russell King (Oracle)
Cc: Giuseppe Cavallaro, Alexandre Torgue, Jose Abreu,
David S. Miller, Jakub Kicinski, Voon Weifeng, Ong Boon Leong,
Arnd Bergmann, kernel test robot, Dan Carpenter, Networking,
Linux ARM, Linux Kernel Mailing List
On Mon, Sep 27, 2021 at 3:27 PM Russell King (Oracle)
<linux@armlinux.org.uk> wrote:
> On Mon, Sep 27, 2021 at 12:02:44PM +0200, Arnd Bergmann wrote:
>
> This looks rather weird. rx_irq[] is defined as:
>
> int rx_irq[MTL_MAX_RX_QUEUES];
>
> If "i" were to become MTL_MAX_RX_QUEUES, then the above code overlows
> the array.
>
> So while this may stop gcc-10 complaining, I'd argue that making the
> new test ">=" rather than ">" would have also made it look correct.
Indeed, thanks for pointing this out. I have sent a follow-up with
that change now.
Arnd
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] [RESEND] net: stmmac: fix gcc-10 -Wrestrict warning
@ 2021-09-27 13:59 ` Arnd Bergmann
0 siblings, 0 replies; 8+ messages in thread
From: Arnd Bergmann @ 2021-09-27 13:59 UTC (permalink / raw)
To: Russell King (Oracle)
Cc: Giuseppe Cavallaro, Alexandre Torgue, Jose Abreu,
David S. Miller, Jakub Kicinski, Voon Weifeng, Ong Boon Leong,
Arnd Bergmann, kernel test robot, Dan Carpenter, Networking,
Linux ARM, Linux Kernel Mailing List
On Mon, Sep 27, 2021 at 3:27 PM Russell King (Oracle)
<linux@armlinux.org.uk> wrote:
> On Mon, Sep 27, 2021 at 12:02:44PM +0200, Arnd Bergmann wrote:
>
> This looks rather weird. rx_irq[] is defined as:
>
> int rx_irq[MTL_MAX_RX_QUEUES];
>
> If "i" were to become MTL_MAX_RX_QUEUES, then the above code overlows
> the array.
>
> So while this may stop gcc-10 complaining, I'd argue that making the
> new test ">=" rather than ">" would have also made it look correct.
Indeed, thanks for pointing this out. I have sent a follow-up with
that change now.
Arnd
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 8+ messages in thread