[PATCH v3] wifi: cfg80211: replace strlcpy() with strscpy()

[PATCH v3] wifi: cfg80211: replace 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().

Direct replacement is safe here since WIPHY_ASSIGN is only used by
TRACE macros and the return values are ignored.

[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>
---
v1: https://lore.kernel.org/all/20230612232301.2572316-1-azeemshaikh38@gmail.com/
v2: https://lore.kernel.org/all/20230614134552.2108471-1-azeemshaikh38@gmail.com/

Changes from v1 and v2 - updated patch title.

 net/wireless/trace.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 716a1fa70069..a00da3ebfed5 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -22,7 +22,7 @@
 
 #define MAXNAME		32
 #define WIPHY_ENTRY	__array(char, wiphy_name, 32)
-#define WIPHY_ASSIGN	strlcpy(__entry->wiphy_name, wiphy_name(wiphy), MAXNAME)
+#define WIPHY_ASSIGN	strscpy(__entry->wiphy_name, wiphy_name(wiphy), MAXNAME)
 #define WIPHY_PR_FMT	"%s"
 #define WIPHY_PR_ARG	__entry->wiphy_name
 
-- 
2.41.0.162.gfafddb0af9-goog

Re: [PATCH v3] wifi: cfg80211: replace strlcpy() with strscpy()

[Kalle Valo]

Azeem Shaikh <azeemshaikh38@gmail.com> writes:

> 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().
>
> Direct replacement is safe here since WIPHY_ASSIGN is only used by
> TRACE macros and the return values are ignored.
>
> [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>
> ---
> v1: https://lore.kernel.org/all/20230612232301.2572316-1-azeemshaikh38@gmail.com/
> v2: https://lore.kernel.org/all/20230614134552.2108471-1-azeemshaikh38@gmail.com/

In the change log (after the "---" line) you should also describe what
changes you made, more info in the wiki below. In this case it's clear
as the patch is simple but please keep this in mind for future patches.

No need to resend because of this.

-- 
https://patchwork.kernel.org/project/linux-wireless/list/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

Re: [PATCH v3] wifi: cfg80211: replace strlcpy() with strscpy()

[Azeem Shaikh]

On Wed, Jun 14, 2023 at 10:24 AM Kalle Valo <kvalo@kernel.org> wrote:
>
> Azeem Shaikh <azeemshaikh38@gmail.com> writes:
>
> > 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().
> >
> > Direct replacement is safe here since WIPHY_ASSIGN is only used by
> > TRACE macros and the return values are ignored.
> >
> > [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>
> > ---
> > v1: https://lore.kernel.org/all/20230612232301.2572316-1-azeemshaikh38@gmail.com/
> > v2: https://lore.kernel.org/all/20230614134552.2108471-1-azeemshaikh38@gmail.com/
>
> In the change log (after the "---" line) you should also describe what
> changes you made, more info in the wiki below. In this case it's clear
> as the patch is simple but please keep this in mind for future patches.
>
> No need to resend because of this.
>

Thanks Kalle. I did have the below line in my changelog. For future
patches, do you mean that changelog descriptions need to be more
specific than this? For example - updated title from "x" -> "y"?

> Changes from v1 and v2 - updated patch title.

Re: [PATCH v3] wifi: cfg80211: replace strlcpy() with strscpy()

[Kalle Valo]

Azeem Shaikh <azeemshaikh38@gmail.com> writes:

> On Wed, Jun 14, 2023 at 10:24 AM Kalle Valo <kvalo@kernel.org> wrote:
>
>>
>> Azeem Shaikh <azeemshaikh38@gmail.com> writes:
>>
>> > 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().
>> >
>> > Direct replacement is safe here since WIPHY_ASSIGN is only used by
>> > TRACE macros and the return values are ignored.
>> >
>> > [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>
>> > ---
>> > v1: https://lore.kernel.org/all/20230612232301.2572316-1-azeemshaikh38@gmail.com/
>> > v2: https://lore.kernel.org/all/20230614134552.2108471-1-azeemshaikh38@gmail.com/
>>
>> In the change log (after the "---" line) you should also describe what
>> changes you made, more info in the wiki below. In this case it's clear
>> as the patch is simple but please keep this in mind for future patches.
>>
>> No need to resend because of this.
>>
>
> Thanks Kalle. I did have the below line in my changelog. For future
> patches, do you mean that changelog descriptions need to be more
> specific than this? For example - updated title from "x" -> "y"?
>
>> Changes from v1 and v2 - updated patch title.

Ah, I missed that because the format was not what we usually use. I
recommend something like this:

v3:

* add bar

v2:

* https://
* fix foo

v1:

* https://

-- 
https://patchwork.kernel.org/project/linux-wireless/list/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

Re: [PATCH v3] wifi: cfg80211: replace strlcpy() with strscpy()

[Azeem Shaikh]

On Wed, Jun 14, 2023 at 11:15 AM Kalle Valo <kvalo@kernel.org> wrote:
>
> Azeem Shaikh <azeemshaikh38@gmail.com> writes:
>
> > On Wed, Jun 14, 2023 at 10:24 AM Kalle Valo <kvalo@kernel.org> wrote:
> >
> >>
> >> Azeem Shaikh <azeemshaikh38@gmail.com> writes:
> >>
> >> > 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().
> >> >
> >> > Direct replacement is safe here since WIPHY_ASSIGN is only used by
> >> > TRACE macros and the return values are ignored.
> >> >
> >> > [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>
> >> > ---
> >> > v1: https://lore.kernel.org/all/20230612232301.2572316-1-azeemshaikh38@gmail.com/
> >> > v2: https://lore.kernel.org/all/20230614134552.2108471-1-azeemshaikh38@gmail.com/
> >>
> >> In the change log (after the "---" line) you should also describe what
> >> changes you made, more info in the wiki below. In this case it's clear
> >> as the patch is simple but please keep this in mind for future patches.
> >>
> >> No need to resend because of this.
> >>
> >
> > Thanks Kalle. I did have the below line in my changelog. For future
> > patches, do you mean that changelog descriptions need to be more
> > specific than this? For example - updated title from "x" -> "y"?
> >
> >> Changes from v1 and v2 - updated patch title.
>
> Ah, I missed that because the format was not what we usually use. I
> recommend something like this:
>
> v3:
>
> * add bar
>
> v2:
>
> * https://
> * fix foo
>
> v1:
>
> * https://
>

Got it, thanks a lot!