2019-05-29 11:37:03

by Mathieu Malaterre

Subject: [PATCH] hfsplus: Replace strncpy with memcpy

Function strncpy was used to copy a fixed size buffer. Since
NUL-terminating string is not required here, prefer a memcpy function.
The generated code (ppc32) remains the same.

Silence the following warning triggered using W=1:

fs/hfsplus/xattr.c:410:3: warning: 'strncpy' output truncated before terminating nul copying 4 bytes from a string of the same length [-Wstringop-truncation]

Signed-off-by: Mathieu Malaterre <[email protected]>
---
fs/hfsplus/xattr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index d5403b4004c9..bb0b27d88e50 100644
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -407,7 +407,7 @@ static int copy_name(char *buffer, const char *xattr_name, int name_len)
int offset = 0;

if (!is_known_namespace(xattr_name)) {
- strncpy(buffer, XATTR_MAC_OSX_PREFIX, XATTR_MAC_OSX_PREFIX_LEN);
+ memcpy(buffer, XATTR_MAC_OSX_PREFIX, XATTR_MAC_OSX_PREFIX_LEN);
offset += XATTR_MAC_OSX_PREFIX_LEN;
len += XATTR_MAC_OSX_PREFIX_LEN;
}
--
2.20.1

2019-05-29 16:51:02

by Viacheslav Dubeyko

Subject: Re: [PATCH] hfsplus: Replace strncpy with memcpy

On Wed, 2019-05-29 at 13:33 +0200, Mathieu Malaterre wrote:
> Function strncpy was used to copy a fixed size buffer. Since
> NUL-terminating string is not required here, prefer a memcpy
> function.
> The generated code (ppc32) remains the same.
>
> Silence the following warning triggered using W=1:
>
>   fs/hfsplus/xattr.c:410:3: warning: 'strncpy' output truncated
> before terminating nul copying 4 bytes from a string of the same
> length [-Wstringop-truncation]
>
> Signed-off-by: Mathieu Malaterre <[email protected]>
> ---
>  fs/hfsplus/xattr.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
> index d5403b4004c9..bb0b27d88e50 100644
> --- a/fs/hfsplus/xattr.c
> +++ b/fs/hfsplus/xattr.c
> @@ -407,7 +407,7 @@ static int copy_name(char *buffer, const char
> *xattr_name, int name_len)
>   int offset = 0;
>  
>   if (!is_known_namespace(xattr_name)) {
> - strncpy(buffer, XATTR_MAC_OSX_PREFIX,
> XATTR_MAC_OSX_PREFIX_LEN);
> + memcpy(buffer, XATTR_MAC_OSX_PREFIX,
> XATTR_MAC_OSX_PREFIX_LEN);
>   offset += XATTR_MAC_OSX_PREFIX_LEN;
>   len += XATTR_MAC_OSX_PREFIX_LEN;
>   }

Looks good. I don't see any troubles here.

Reviewed-by: Vyacheslav Dubeyko <[email protected]>

Thanks,
Vyacheslav Dubeyko.