[PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[Thorsten Blum]

The symlink name was previously duplicated using an explicit kmalloc()
followed by strcpy(), which is deprecated [1]. Replace this open-coded
string duplication with kstrdup(), which allocates and copies the
symlink name with a single helper function.

Remove the local variable 'size' and set 'i_size' directly using
strlen(cp), which is equivalent to the previous value of 'size'.

This simplifies the code, uses common string-handling helpers, and
removes the deprecated use of strcpy().

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 fs/autofs/root.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/autofs/root.c b/fs/autofs/root.c
index 2c31002b314a..186e960f1e23 100644
--- a/fs/autofs/root.c
+++ b/fs/autofs/root.c
@@ -7,6 +7,7 @@
 
 #include <linux/capability.h>
 #include <linux/compat.h>
+#include <linux/string.h>
 
 #include "autofs_i.h"
 
@@ -578,7 +579,6 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
 	struct autofs_info *ino = autofs_dentry_ino(dentry);
 	struct autofs_info *p_ino;
 	struct inode *inode;
-	size_t size = strlen(symname);
 	char *cp;
 
 	pr_debug("%s <- %pd\n", symname, dentry);
@@ -589,19 +589,17 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
 
 	autofs_del_active(dentry);
 
-	cp = kmalloc(size + 1, GFP_KERNEL);
+	cp = kstrdup(symname, GFP_KERNEL);
 	if (!cp)
 		return -ENOMEM;
 
-	strcpy(cp, symname);
-
 	inode = autofs_get_inode(dir->i_sb, S_IFLNK | 0555);
 	if (!inode) {
 		kfree(cp);
 		return -ENOMEM;
 	}
 	inode->i_private = cp;
-	inode->i_size = size;
+	inode->i_size = strlen(cp);
 
 	d_make_persistent(dentry, inode);
 	p_ino = autofs_dentry_ino(dentry->d_parent);
-- 
Thorsten Blum <thorsten.blum@linux.dev>
GPG: 1D60 735E 8AEF 3BE4 73B6  9D84 7336 78FD 8DFE EAD4

[PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[Thorsten Blum]

The symlink name was previously duplicated using an explicit kmalloc()
followed by strcpy(), which is deprecated [1]. Replace this open-coded
string duplication with kstrdup(), which allocates and copies the
symlink name with a single helper function.

Remove the local variable 'size' and set 'i_size' directly using
strlen(cp), which is equivalent to the previous value of 'size'.

This simplifies the code, uses common string-handling helpers, and
removes the deprecated use of strcpy().

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 fs/autofs/root.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/autofs/root.c b/fs/autofs/root.c
index 2c31002b314a..186e960f1e23 100644
--- a/fs/autofs/root.c
+++ b/fs/autofs/root.c
@@ -7,6 +7,7 @@
 
 #include <linux/capability.h>
 #include <linux/compat.h>
+#include <linux/string.h>
 
 #include "autofs_i.h"
 
@@ -578,7 +579,6 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
 	struct autofs_info *ino = autofs_dentry_ino(dentry);
 	struct autofs_info *p_ino;
 	struct inode *inode;
-	size_t size = strlen(symname);
 	char *cp;
 
 	pr_debug("%s <- %pd\n", symname, dentry);
@@ -589,19 +589,17 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
 
 	autofs_del_active(dentry);
 
-	cp = kmalloc(size + 1, GFP_KERNEL);
+	cp = kstrdup(symname, GFP_KERNEL);
 	if (!cp)
 		return -ENOMEM;
 
-	strcpy(cp, symname);
-
 	inode = autofs_get_inode(dir->i_sb, S_IFLNK | 0555);
 	if (!inode) {
 		kfree(cp);
 		return -ENOMEM;
 	}
 	inode->i_private = cp;
-	inode->i_size = size;
+	inode->i_size = strlen(cp);
 
 	d_make_persistent(dentry, inode);
 	p_ino = autofs_dentry_ino(dentry->d_parent);
-- 
Thorsten Blum <thorsten.blum@linux.dev>
GPG: 1D60 735E 8AEF 3BE4 73B6  9D84 7336 78FD 8DFE EAD4

Re: [PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[Ian Kent]

On 27/1/26 09:36, Thorsten Blum wrote:
> The symlink name was previously duplicated using an explicit kmalloc()
> followed by strcpy(), which is deprecated [1]. Replace this open-coded
> string duplication with kstrdup(), which allocates and copies the
> symlink name with a single helper function.
>
> Remove the local variable 'size' and set 'i_size' directly using
> strlen(cp), which is equivalent to the previous value of 'size'.
>
> This simplifies the code, uses common string-handling helpers, and
> removes the deprecated use of strcpy().
>
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
> ---
>   fs/autofs/root.c | 8 +++-----
>   1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/fs/autofs/root.c b/fs/autofs/root.c
> index 2c31002b314a..186e960f1e23 100644
> --- a/fs/autofs/root.c
> +++ b/fs/autofs/root.c
> @@ -7,6 +7,7 @@
>   
>   #include <linux/capability.h>
>   #include <linux/compat.h>
> +#include <linux/string.h>
>   
>   #include "autofs_i.h"
>   
> @@ -578,7 +579,6 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
>   	struct autofs_info *ino = autofs_dentry_ino(dentry);
>   	struct autofs_info *p_ino;
>   	struct inode *inode;
> -	size_t size = strlen(symname);
>   	char *cp;
>   
>   	pr_debug("%s <- %pd\n", symname, dentry);
> @@ -589,19 +589,17 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
>   
>   	autofs_del_active(dentry);
>   
> -	cp = kmalloc(size + 1, GFP_KERNEL);
> +	cp = kstrdup(symname, GFP_KERNEL);
>   	if (!cp)
>   		return -ENOMEM;
>   
> -	strcpy(cp, symname);
> -
>   	inode = autofs_get_inode(dir->i_sb, S_IFLNK | 0555);
>   	if (!inode) {
>   		kfree(cp);
>   		return -ENOMEM;
>   	}
>   	inode->i_private = cp;
> -	inode->i_size = size;
> +	inode->i_size = strlen(cp);
>   
>   	d_make_persistent(dentry, inode);
>   	p_ino = autofs_dentry_ino(dentry->d_parent);

Looks fine to me.

Acked by: Ian Kent <raven@themaw.net>

Christian, is there anything else I need to do for this?


Ian

Re: [PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[Thorsten Blum]

On 27. Jan 2026, at 03:14, Ian Kent wrote:
> On 27/1/26 09:36, Thorsten Blum wrote:
>> The symlink name was previously duplicated using an explicit kmalloc()
>> followed by strcpy(), which is deprecated [1]. Replace this open-coded
>> string duplication with kstrdup(), which allocates and copies the
>> symlink name with a single helper function.
>> 
>> Remove the local variable 'size' and set 'i_size' directly using
>> strlen(cp), which is equivalent to the previous value of 'size'.
>> 
>> This simplifies the code, uses common string-handling helpers, and
>> removes the deprecated use of strcpy().
>> 
>> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
>> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
>> ---
>>  fs/autofs/root.c | 8 +++-----
>>  1 file changed, 3 insertions(+), 5 deletions(-)
>> 
>> [...]
> 
> Looks fine to me.
> 
> Acked by: Ian Kent <raven@themaw.net>

Your tag is missing a hyphen and tools like b4 don't recognize it like
this. Correct would be:

	Acked-by: Ian Kent <raven@themaw.net>

> Christian, is there anything else I need to do for this?

Thanks,
Thorsten

[PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[Thorsten Blum]

The symlink name was previously duplicated using an explicit kmalloc()
followed by strcpy(), which is deprecated [1]. Replace this open-coded
string duplication with kstrdup(), which allocates and copies the
symlink name with a single helper function.

Remove the local variable 'size' and set 'i_size' directly using
strlen(cp), which is equivalent to the previous value of 'size'.

This simplifies the code, uses common string-handling helpers, and
removes the deprecated use of strcpy().

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 fs/autofs/root.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/autofs/root.c b/fs/autofs/root.c
index 2c31002b314a..186e960f1e23 100644
--- a/fs/autofs/root.c
+++ b/fs/autofs/root.c
@@ -7,6 +7,7 @@
 
 #include <linux/capability.h>
 #include <linux/compat.h>
+#include <linux/string.h>
 
 #include "autofs_i.h"
 
@@ -578,7 +579,6 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
 	struct autofs_info *ino = autofs_dentry_ino(dentry);
 	struct autofs_info *p_ino;
 	struct inode *inode;
-	size_t size = strlen(symname);
 	char *cp;
 
 	pr_debug("%s <- %pd\n", symname, dentry);
@@ -589,19 +589,17 @@ static int autofs_dir_symlink(struct mnt_idmap *idmap,
 
 	autofs_del_active(dentry);
 
-	cp = kmalloc(size + 1, GFP_KERNEL);
+	cp = kstrdup(symname, GFP_KERNEL);
 	if (!cp)
 		return -ENOMEM;
 
-	strcpy(cp, symname);
-
 	inode = autofs_get_inode(dir->i_sb, S_IFLNK | 0555);
 	if (!inode) {
 		kfree(cp);
 		return -ENOMEM;
 	}
 	inode->i_private = cp;
-	inode->i_size = size;
+	inode->i_size = strlen(cp);
 
 	d_make_persistent(dentry, inode);
 	p_ino = autofs_dentry_ino(dentry->d_parent);

Re: [PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[Christian Brauner]

On Wed, 18 Mar 2026 01:12:21 +0100, Thorsten Blum wrote:
> The symlink name was previously duplicated using an explicit kmalloc()
> followed by strcpy(), which is deprecated [1]. Replace this open-coded
> string duplication with kstrdup(), which allocates and copies the
> symlink name with a single helper function.
> 
> Remove the local variable 'size' and set 'i_size' directly using
> strlen(cp), which is equivalent to the previous value of 'size'.
> 
> [...]

Applied to the vfs-7.1.misc branch of the vfs/vfs.git tree.
Patches in the vfs-7.1.misc branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs-7.1.misc

[1/1] autofs: replace manual symlink buffer allocation in autofs_dir_symlink
      https://git.kernel.org/vfs/vfs/c/f8909447894a

Re: [PATCH RESEND] autofs: replace manual symlink buffer allocation in autofs_dir_symlink

[Christian Brauner]

On Wed, Mar 18, 2026 at 01:12:21AM +0100, Thorsten Blum wrote:
> The symlink name was previously duplicated using an explicit kmalloc()
> followed by strcpy(), which is deprecated [1]. Replace this open-coded
> string duplication with kstrdup(), which allocates and copies the
> symlink name with a single helper function.
> 
> Remove the local variable 'size' and set 'i_size' directly using
> strlen(cp), which is equivalent to the previous value of 'size'.
> 
> This simplifies the code, uses common string-handling helpers, and
> removes the deprecated use of strcpy().
> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
> Acked-by: Ian Kent <raven@themaw.net>
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
> ---

Ideally always Cc fsdevel. This way the tooling sees it right away.