2023-05-17 14:52:18

by Azeem Shaikh

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

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 <[email protected]>
---
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);



2023-05-17 19:23:42

by Kees Cook

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

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 <[email protected]>

Reviewed-by: Kees Cook <[email protected]>

--
Kees Cook

2023-05-17 21:24:36

by Tyrel Datwyler

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

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 <[email protected]>

Acked-by: Tyrel Datwyler <[email protected]>


2023-05-22 20:14:54

by Kees Cook

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

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