[PATCH] scsi: ibmvscsi: Replace all non-returning strlcpy with strscpy

[PATCH] scsi: ibmvscsi: Replace all non-returning strlcpy with strscpy

[Azeem Shaikh]

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
---
 drivers/scsi/ibmvscsi/ibmvscsi.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index 63f32f843e75..59599299615d 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -250,7 +250,7 @@ static void gather_partition_info(void)
 
 	ppartition_name = of_get_property(of_root, "ibm,partition-name", NULL);
 	if (ppartition_name)
-		strlcpy(partition_name, ppartition_name,
+		strscpy(partition_name, ppartition_name,
 				sizeof(partition_name));
 	p_number_ptr = of_get_property(of_root, "ibm,partition-no", NULL);
 	if (p_number_ptr)
@@ -1282,12 +1282,12 @@ static void send_mad_capabilities(struct ibmvscsi_host_data *hostdata)
 	if (hostdata->client_migrated)
 		hostdata->caps.flags |= cpu_to_be32(CLIENT_MIGRATED);
 
-	strlcpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
+	strscpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
 		sizeof(hostdata->caps.name));
 
 	location = of_get_property(of_node, "ibm,loc-code", NULL);
 	location = location ? location : dev_name(hostdata->dev);
-	strlcpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
+	strscpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
 
 	req->common.type = cpu_to_be32(VIOSRP_CAPABILITIES_TYPE);
 	req->buffer = cpu_to_be64(hostdata->caps_addr);

Re: [PATCH] scsi: ibmvscsi: Replace all non-returning strlcpy with strscpy

[Kees Cook]

On Wed, May 17, 2023 at 02:34:09PM +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> No return values were used, so direct replacement is safe.
> 
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> [2] https://github.com/KSPP/linux/issues/89
> 
> Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook

Re: [PATCH] scsi: ibmvscsi: Replace all non-returning strlcpy with strscpy

[Tyrel Datwyler]

On 5/17/23 07:34, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> No return values were used, so direct replacement is safe.
> 
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> [2] https://github.com/KSPP/linux/issues/89
> 
> Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>

Acked-by: Tyrel Datwyler <tyreld@linux.ibm.com>

Re: [PATCH] scsi: ibmvscsi: Replace all non-returning strlcpy with strscpy

[Kees Cook]

On Wed, 17 May 2023 14:34:09 +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> No return values were used, so direct replacement is safe.
> 
> [...]

Applied to for-next/hardening, thanks!

[1/1] scsi: ibmvscsi: Replace all non-returning strlcpy with strscpy
      https://git.kernel.org/kees/c/015f6618194e

-- 
Kees Cook