[PATCH 0/3] PCI: Replace use of snprintf() with scnprintf() in show() functions

[PATCH 0/3] PCI: Replace use of snprintf() with scnprintf() in show() functions

[Krzysztof Wilczyński]

Replace use of snprintf() with scnprintf() in order to adhere to the
rules in Documentation/filesystems/sysfs.txt, as per:

  show() must not use snprintf() when formatting the value to be
  returned to user space. If you can guarantee that an overflow
  will never happen you can use sprintf() otherwise you must use
  scnprintf().

Also resolve the following Coccinelle warnings, for example:

  drivers/pci/p2pdma.c:69:8-16: WARNING: use scnprintf or sprintf
  drivers/pci/p2pdma.c:78:8-16: WARNING: use scnprintf or sprintf
  drivers/pci/p2pdma.c:56:8-16: WARNING: use scnprintf or sprintf

The Coccinelle warning was added in commit abfc19ff202d ("coccinelle:
api: add device_attr_show script").

There is no change to the functionality.

Related:
  https://patchwork.kernel.org/patch/9946759/#20969333
  https://lwn.net/Articles/69419

Krzysztof Wilczyński (3):
  PCI: Replace use of snprintf() with scnprintf() in
    resource_alignment_show()
  PCI: sysfs: Replace use of snprintf() with scnprintf() in
    driver_override_show()
  PCI/P2PDMA: Replace use of snprintf() with scnprintf() in show()
    functions

 drivers/pci/p2pdma.c    | 8 ++++----
 drivers/pci/pci-sysfs.c | 2 +-
 drivers/pci/pci.c       | 2 +-
 3 files changed, 6 insertions(+), 6 deletions(-)

-- 
2.28.0

[PATCH 1/3] PCI: Replace use of snprintf() with scnprintf() in resource_alignment_show()

[Krzysztof Wilczyński]

Replace use of snprintf() with scnprintf() in order to adhere to the
rules in Documentation/filesystems/sysfs.txt, as per:

  show() must not use snprintf() when formatting the value to be
  returned to user space. If you can guarantee that an overflow
  will never happen you can use sprintf() otherwise you must use
  scnprintf().

There is no change to the functionality.

Related:
  https://patchwork.kernel.org/patch/9946759/#20969333
  https://lwn.net/Articles/69419

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
---
 drivers/pci/pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index e39c5499770f..e6c904cbf983 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -6350,7 +6350,7 @@ static ssize_t resource_alignment_show(struct bus_type *bus, char *buf)
 
 	spin_lock(&resource_alignment_lock);
 	if (resource_alignment_param)
-		count = snprintf(buf, PAGE_SIZE, "%s", resource_alignment_param);
+		count = scnprintf(buf, PAGE_SIZE, "%s", resource_alignment_param);
 	spin_unlock(&resource_alignment_lock);
 
 	/*
-- 
2.28.0

[PATCH 2/3] PCI: sysfs: Replace use of snprintf() with scnprintf() in driver_override_show()

[Krzysztof Wilczyński]

Replace use of snprintf() with scnprintf() in order to adhere to the
rules in Documentation/filesystems/sysfs.txt, as per:

  show() must not use snprintf() when formatting the value to be
  returned to user space. If you can guarantee that an overflow
  will never happen you can use sprintf() otherwise you must use
  scnprintf().

There is no change to the functionality.

Related:
  https://patchwork.kernel.org/patch/9946759/#20969333
  https://lwn.net/Articles/69419

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
---
 drivers/pci/pci-sysfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 6d78df981d41..ed66d387e913 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -574,7 +574,7 @@ static ssize_t driver_override_show(struct device *dev,
 	ssize_t len;
 
 	device_lock(dev);
-	len = snprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override);
+	len = scnprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override);
 	device_unlock(dev);
 	return len;
 }
-- 
2.28.0

[PATCH 3/3] PCI/P2PDMA: Replace use of snprintf() with scnprintf() in show() functions

[Krzysztof Wilczyński]

Replace use of snprintf() with scnprintf() in the functions size_show(),
available_show() and published_show() in order to adhere to the rules in
Documentation/filesystems/sysfs.txt, as per:

  show() must not use snprintf() when formatting the value to be
  returned to user space. If you can guarantee that an overflow
  will never happen you can use sprintf() otherwise you must use
  scnprintf().

Also resolve the following Coccinelle warnings:

  drivers/pci/p2pdma.c:69:8-16: WARNING: use scnprintf or sprintf
  drivers/pci/p2pdma.c:78:8-16: WARNING: use scnprintf or sprintf
  drivers/pci/p2pdma.c:56:8-16: WARNING: use scnprintf or sprintf

The Coccinelle warning was added in commit abfc19ff202d ("coccinelle:
api: add device_attr_show script").

There is no change to the functionality.

Related:
  https://patchwork.kernel.org/patch/9946759/#20969333
  https://lwn.net/Articles/69419

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
---
 drivers/pci/p2pdma.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
index f357f9a32b3a..c4714438d39c 100644
--- a/drivers/pci/p2pdma.c
+++ b/drivers/pci/p2pdma.c
@@ -53,7 +53,7 @@ static ssize_t size_show(struct device *dev, struct device_attribute *attr,
 	if (pdev->p2pdma->pool)
 		size = gen_pool_size(pdev->p2pdma->pool);
 
-	return snprintf(buf, PAGE_SIZE, "%zd\n", size);
+	return scnprintf(buf, PAGE_SIZE, "%zd\n", size);
 }
 static DEVICE_ATTR_RO(size);
 
@@ -66,7 +66,7 @@ static ssize_t available_show(struct device *dev, struct device_attribute *attr,
 	if (pdev->p2pdma->pool)
 		avail = gen_pool_avail(pdev->p2pdma->pool);
 
-	return snprintf(buf, PAGE_SIZE, "%zd\n", avail);
+	return scnprintf(buf, PAGE_SIZE, "%zd\n", avail);
 }
 static DEVICE_ATTR_RO(available);
 
@@ -75,8 +75,8 @@ static ssize_t published_show(struct device *dev, struct device_attribute *attr,
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n",
-			pdev->p2pdma->p2pmem_published);
+	return scnprintf(buf, PAGE_SIZE, "%d\n",
+			 pdev->p2pdma->p2pmem_published);
 }
 static DEVICE_ATTR_RO(published);
 
-- 
2.28.0

Re: [PATCH 0/3] PCI: Replace use of snprintf() with scnprintf() in show() functions

[Bjorn Helgaas]

On Mon, Aug 24, 2020 at 11:39:15PM +0000, Krzysztof Wilczyński wrote:
> Replace use of snprintf() with scnprintf() in order to adhere to the
> rules in Documentation/filesystems/sysfs.txt, as per:
> 
>   show() must not use snprintf() when formatting the value to be
>   returned to user space. If you can guarantee that an overflow
>   will never happen you can use sprintf() otherwise you must use
>   scnprintf().
> 
> Also resolve the following Coccinelle warnings, for example:
> 
>   drivers/pci/p2pdma.c:69:8-16: WARNING: use scnprintf or sprintf
>   drivers/pci/p2pdma.c:78:8-16: WARNING: use scnprintf or sprintf
>   drivers/pci/p2pdma.c:56:8-16: WARNING: use scnprintf or sprintf
> 
> The Coccinelle warning was added in commit abfc19ff202d ("coccinelle:
> api: add device_attr_show script").
> 
> There is no change to the functionality.
> 
> Related:
>   https://patchwork.kernel.org/patch/9946759/#20969333
>   https://lwn.net/Articles/69419
> 
> Krzysztof Wilczyński (3):
>   PCI: Replace use of snprintf() with scnprintf() in
>     resource_alignment_show()
>   PCI: sysfs: Replace use of snprintf() with scnprintf() in
>     driver_override_show()
>   PCI/P2PDMA: Replace use of snprintf() with scnprintf() in show()
>     functions
> 
>  drivers/pci/p2pdma.c    | 8 ++++----
>  drivers/pci/pci-sysfs.c | 2 +-
>  drivers/pci/pci.c       | 2 +-
>  3 files changed, 6 insertions(+), 6 deletions(-)

Squashed together and applied to pci/misc for v5.10, thanks!