[PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()

[PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()

[Ajith P V]

The `strcpy()` function is deprecated and moving towards code-tree
elimination. Replacing it with `strscpy()` fixes potential buffer
overflow vectors by ensuring safe NULL-termination based on the
destination buffer size limit [1][2].

In `tipc_bearer_get_name()`, the 'name' parameter decays into a pointer,
meaning `sizeof()` cannot capture the underlying array bounds directly.
However, all parent callers allocate this buffer using the
TIPC_MAX_BEARER_NAME macro.

Replace strcpy() with strscpy() using TIPC_MAX_BEARER_NAME as the
explicit destination bound length.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
Link: https://github.com/KSPP/linux/issues/88 [2]

Signed-off-by: Ajith P V <ajithpv.linux@gmail.com>
---
v3:
  - Fix patch title as suggested by Tung Quang Nguyen.
  - No code changes from v2.
v2:
  - Target net-next tree instead of standard net tree as requested by Tung Quang Nguyen.
  - No code changes from v1.

 net/tipc/bearer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index 05dcd2f9e887..951bb474c7d4 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -209,7 +209,7 @@ int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id)
 	if (!b)
 		return -EINVAL;
 
-	strcpy(name, b->name);
+	strscpy(name, b->name, TIPC_MAX_BEARER_NAME);
 	return 0;
 }
 
-- 
2.43.0

Re: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()

[Tung Quang Nguyen]

> Subject: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()
It seems your patch is not based on net-next tree:
"Conflicts with pending/net patches (net-next-2026-08-13--12-00): error: patch failed: net/tipc/bearer.c:209 error: net/tipc/bearer.c: patch does not apply"

Could you please apply your patch to net-next tree and resubmit ?

Re: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()

[Ajith P V]

> It seems your patch is not based on net-next tree:
> "Conflicts with pending/net patches (net-next-2026-08-13--12-00): error: patch failed: net/tipc/bearer.c:209 error: net/tipc/bearer.c: patch does not apply"

> Could you please apply your patch to net-next tree and resubmit ?

First time net contributor and I'm a bit confused here. When I cloned the net-next, it applied the same patch without the error as shown below:
<path of the linux tree >net-next$ ls
arch   certs    CREDITS  Documentation  fs       init      ipc     Kconfig  lib       MAINTAINERS  mm   README  samples  security  tools  virt
block  COPYING  crypto   drivers        include  io_uring  Kbuild  kernel   LICENSES  Makefile     net  rust    scripts  sound     usr
<path of the linux tree/net-next$ git remote -v
origin	https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git (fetch)
origin	https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git (push)
<path of the linux tree/net-next$ git branch
* main
<path of the linux tree/net-next$ git am ../../patches/v3-0001-tipc-replace-deprecated-strcpy-with-strscpy-in-ti.patch
Applying: tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()
<path of the linux tree/net-next$

May I know the correct way of getting the latest net-next so that I can reproduce the same error and patch on top of it?

Re: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()

[Tung Quang Nguyen]

> May I know the correct way of getting the latest net-next so that I can reproduce the same error and patch on top of it?
net tree: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git
net-next tree: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git

Re: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()

[Ajith P V]

> net tree: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git
> net-next tree: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git

Thank you. I tried the correct net-next tree. The same patch applied successfully here also as shown below.

<path of the linux tree>/net-next$ ls
arch   certs    CREDITS  Documentation  fs       init      ipc     Kconfig  lib       MAINTAINERS  mm   README  samples  security  tools  virt
block  COPYING  crypto   drivers        include  io_uring  Kbuild  kernel   LICENSES  Makefile     net  rust    scripts  sound     usr
<path of the linux tree>/net-next$ git remote -v
origin	https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git (fetch)
origin	https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git (push)
<path of the linux tree>/net-next$ git am ../../patches/v3-0001-tipc-replace-deprecated-strcpy-with-strscpy-in-ti.patch
Applying: tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()
<path of the linux tree>/net-next$ git branch
* main
<path of the linux tree>/net-next$

Am I missing something?

RE: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()

[Tung Quang Nguyen]

>Subject: Re: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in
>tipc_bearer_get_name()
>
>> net tree:
>> https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git
>> net-next tree:
>> https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
>
>Thank you. I tried the correct net-next tree. The same patch applied
>successfully here also as shown below.
>
><path of the linux tree>/net-next$ ls
>arch   certs    CREDITS  Documentation  fs       init      ipc     Kconfig  lib
>MAINTAINERS  mm   README  samples  security  tools  virt
>block  COPYING  crypto   drivers        include  io_uring  Kbuild  kernel   LICENSES
>Makefile     net  rust    scripts  sound     usr
><path of the linux tree>/net-next$ git remote -v
>origin	https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
>(fetch)
>origin	https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
>(push)
><path of the linux tree>/net-next$ git am ../../patches/v3-0001-tipc-replace-
>deprecated-strcpy-with-strscpy-in-ti.patch
>Applying: tipc: replace deprecated strcpy with strscpy in
>tipc_bearer_get_name() <path of the linux tree>/net-next$ git branch
>* main
><path of the linux tree>/net-next$
>
>Am I missing something?

I see that your patch was applied again successfully after failure.
There is one feedback from AI review that I see valid:
[...]
> @@ -209,7 +209,7 @@ int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id)
>  	if (!b)
>  		return -EINVAL;
>  
> -	strcpy(name, b->name);
> +	strscpy(name, b->name, TIPC_MAX_BEARER_NAME);
This isn't a bug, but the destination capacity is now hard-coded in the
body while the interface says nothing about it.  The declaration in
net/tipc/bearer.h is still:
	int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id);
and the comment directly above the implementation only says:
	 *     @name: a pointer to the buffer where the name will be stored.
Should the TIPC_MAX_BEARER_NAME requirement be spelled out in the comment
or in the prototype, so that the interface and the body agree?
In the current tree there is no behavioural change: the only caller is
__tipc_nl_add_monitor() in net/tipc/monitor.c, which declares
char bearer_name[TIPC_MAX_BEARER_NAME], and the source is
char name[TIPC_MAX_BEARER_NAME] in struct tipc_bearer, so the copy can
neither truncate nor overflow.
The strscpy() return value is also discarded, so a future caller passing a
smaller buffer would get a silently truncated name plus a return of 0.
Would passing a size_t len from the caller (sizeof(bearer_name)) and
forwarding strscpy()'s -E2BIG through the existing int return be preferable
to a hard-coded bound?
[...]

Please update your patch and send the new version after Aug 31st. (Because net-next is closed now)

Re: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in tipc_bearer_get_name()

[David Laight]

On Mon, 17 Aug 2026 07:53:53 +0000
Tung Quang Nguyen <tung.quang.nguyen@est.tech> wrote:

> >Subject: Re: [PATCH net-next v3] tipc: replace deprecated strcpy with strscpy in
> >tipc_bearer_get_name()
> >  
> >> net tree:
> >> https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git
> >> net-next tree:
> >> https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git  
> >
> >Thank you. I tried the correct net-next tree. The same patch applied
> >successfully here also as shown below.
> >
> ><path of the linux tree>/net-next$ ls
> >arch   certs    CREDITS  Documentation  fs       init      ipc     Kconfig  lib
> >MAINTAINERS  mm   README  samples  security  tools  virt
> >block  COPYING  crypto   drivers        include  io_uring  Kbuild  kernel   LICENSES
> >Makefile     net  rust    scripts  sound     usr
> ><path of the linux tree>/net-next$ git remote -v
> >origin	https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
> >(fetch)
> >origin	https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
> >(push)
> ><path of the linux tree>/net-next$ git am ../../patches/v3-0001-tipc-replace-
> >deprecated-strcpy-with-strscpy-in-ti.patch
> >Applying: tipc: replace deprecated strcpy with strscpy in
> >tipc_bearer_get_name() <path of the linux tree>/net-next$ git branch
> >* main
> ><path of the linux tree>/net-next$
> >
> >Am I missing something?  
> 
> I see that your patch was applied again successfully after failure.
> There is one feedback from AI review that I see valid:
> [...]
> > @@ -209,7 +209,7 @@ int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id)
> >  	if (!b)
> >  		return -EINVAL;
> >  
> > -	strcpy(name, b->name);
> > +	strscpy(name, b->name, TIPC_MAX_BEARER_NAME);  
> This isn't a bug, but the destination capacity is now hard-coded in the
> body while the interface says nothing about it.  The declaration in
> net/tipc/bearer.h is still:
> 	int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id);
> and the comment directly above the implementation only says:
> 	 *     @name: a pointer to the buffer where the name will be stored.
> Should the TIPC_MAX_BEARER_NAME requirement be spelled out in the comment
> or in the prototype, so that the interface and the body agree?
> In the current tree there is no behavioural change: the only caller is
> __tipc_nl_add_monitor() in net/tipc/monitor.c, which declares
> char bearer_name[TIPC_MAX_BEARER_NAME], and the source is
> char name[TIPC_MAX_BEARER_NAME] in struct tipc_bearer, so the copy can
> neither truncate nor overflow.
> The strscpy() return value is also discarded, so a future caller passing a
> smaller buffer would get a silently truncated name plus a return of 0.
> Would passing a size_t len from the caller (sizeof(bearer_name)) and
> forwarding strscpy()'s -E2BIG through the existing int return be preferable
> to a hard-coded bound?
> [...]
> 
> Please update your patch and send the new version after Aug 31st. (Because net-next is closed now)
> 

One 'solution' to the non-problem is to embed the array in a struct.
Although (IIRC) this is a uapi constant so that may not be completely
possible.

Otherwise I'd ignore the AI review.

	David