2023-05-30 16:06:07

by Azeem Shaikh

[permalink] [raw]
Subject: [PATCH] scsi: libfcoe: 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/fcoe/fcoe_transport.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/fcoe/fcoe_transport.c b/drivers/scsi/fcoe/fcoe_transport.c
index 46b0bf237be1..a48d24af9ac3 100644
--- a/drivers/scsi/fcoe/fcoe_transport.c
+++ b/drivers/scsi/fcoe/fcoe_transport.c
@@ -711,7 +711,7 @@ static struct net_device *fcoe_if_to_netdev(const char *buffer)
char ifname[IFNAMSIZ + 2];

if (buffer) {
- strlcpy(ifname, buffer, IFNAMSIZ);
+ strscpy(ifname, buffer, IFNAMSIZ);
cp = ifname + strlen(ifname);
while (--cp >= ifname && *cp == '\n')
*cp = '\0';



2023-05-30 23:30:11

by Kees Cook

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

On Tue, May 30, 2023 at 03:58:18PM +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

2023-05-31 22:29:18

by Martin K. Petersen

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


Azeem,

> 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 6.5/scsi-staging!

PS. It would help if you could submit changes like these as a series in
the future so I don't have to track each patch individually.

--
Martin K. Petersen Oracle Linux Engineering

2023-05-31 23:19:57

by Azeem Shaikh

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

On Wed, May 31, 2023 at 6:03 PM Martin K. Petersen
<[email protected]> wrote:
>
>
> Azeem,
>
> > 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 6.5/scsi-staging!

Thanks Martin!

>
> PS. It would help if you could submit changes like these as a series in
> the future so I don't have to track each patch individually.
>

Sure, I can do that.

2023-06-08 01:56:10

by Martin K. Petersen

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

On Tue, 30 May 2023 15:58:18 +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 6.5/scsi-queue, thanks!

[1/1] scsi: libfcoe: Replace all non-returning strlcpy with strscpy
https://git.kernel.org/mkp/scsi/c/4dae0262fb99

--
Martin K. Petersen Oracle Linux Engineering