Re: [PATCH] Increase buffer for sysfs path

[Jes Sorensen <Jes.Sorensen@redhat.com>]

Tomasz Majchrzak <tomasz.majchrzak@intel.com> writes:
> 'unacknowledged_bad_blocks' is a long name for sysfs property and it
> makes sysfs path over 50 characters long. Increase buffer to the double
> length of the longest path available in sysfs at the moment.
>
> Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
> ---
>  sysfs.c | 36 ++++++++++++++++++++----------------
>  1 file changed, 20 insertions(+), 16 deletions(-)

Applied!

Thanks,
Jes

>
> diff --git a/sysfs.c b/sysfs.c
> index c7a8e66..fc1f01e 100644
> --- a/sysfs.c
> +++ b/sysfs.c
> @@ -27,6 +27,8 @@
>  #include	<dirent.h>
>  #include	<ctype.h>
>  
> +#define MAX_SYSFS_PATH_LEN	120
> +
>  int load_sys(char *path, char *buf, int len)
>  {
>  	int fd = open(path, O_RDONLY);
> @@ -63,15 +65,15 @@ void sysfs_free(struct mdinfo *sra)
>  
>  int sysfs_open(char *devnm, char *devname, char *attr)
>  {
> -	char fname[50];
> +	char fname[MAX_SYSFS_PATH_LEN];
>  	int fd;
>  
> -	sprintf(fname, "/sys/block/%s/md/", devnm);
> +	snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/", devnm);
>  	if (devname) {
> -		strcat(fname, devname);
> -		strcat(fname, "/");
> +		strncat(fname, devname, MAX_SYSFS_PATH_LEN - strlen(fname));
> +		strncat(fname, "/", MAX_SYSFS_PATH_LEN - strlen(fname));
>  	}
> -	strcat(fname, attr);
> +	strncat(fname, attr, MAX_SYSFS_PATH_LEN - strlen(fname));
>  	fd = open(fname, O_RDWR);
>  	if (fd < 0 && errno == EACCES)
>  		fd = open(fname, O_RDONLY);
> @@ -396,15 +398,17 @@ unsigned long long get_component_size(int fd)
>  	 * This returns in units of sectors.
>  	 */
>  	struct stat stb;
> -	char fname[50];
> +	char fname[MAX_SYSFS_PATH_LEN];
>  	int n;
>  	if (fstat(fd, &stb))
>  		return 0;
>  	if (major(stb.st_rdev) != (unsigned)get_mdp_major())
> -		sprintf(fname, "/sys/block/md%d/md/component_size",
> +		snprintf(fname, MAX_SYSFS_PATH_LEN,
> +			"/sys/block/md%d/md/component_size",
>  			(int)minor(stb.st_rdev));
>  	else
> -		sprintf(fname, "/sys/block/md_d%d/md/component_size",
> +		snprintf(fname, MAX_SYSFS_PATH_LEN,
> +			"/sys/block/md_d%d/md/component_size",
>  			(int)minor(stb.st_rdev)>>MdpMinorShift);
>  	fd = open(fname, O_RDONLY);
>  	if (fd < 0)
> @@ -420,11 +424,11 @@ unsigned long long get_component_size(int fd)
>  int sysfs_set_str(struct mdinfo *sra, struct mdinfo *dev,
>  		  char *name, char *val)
>  {
> -	char fname[50];
> +	char fname[MAX_SYSFS_PATH_LEN];
>  	unsigned int n;
>  	int fd;
>  
> -	sprintf(fname, "/sys/block/%s/md/%s/%s",
> +	snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/%s/%s",
>  		sra->sys_name, dev?dev->sys_name:"", name);
>  	fd = open(fname, O_WRONLY);
>  	if (fd < 0)
> @@ -457,11 +461,11 @@ int sysfs_set_num_signed(struct mdinfo *sra, struct mdinfo *dev,
>  
>  int sysfs_uevent(struct mdinfo *sra, char *event)
>  {
> -	char fname[50];
> +	char fname[MAX_SYSFS_PATH_LEN];
>  	int n;
>  	int fd;
>  
> -	sprintf(fname, "/sys/block/%s/uevent",
> +	snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/uevent",
>  		sra->sys_name);
>  	fd = open(fname, O_WRONLY);
>  	if (fd < 0)
> @@ -478,10 +482,10 @@ int sysfs_uevent(struct mdinfo *sra, char *event)
>  
>  int sysfs_attribute_available(struct mdinfo *sra, struct mdinfo *dev, char *name)
>  {
> -	char fname[50];
> +	char fname[MAX_SYSFS_PATH_LEN];
>  	struct stat st;
>  
> -	sprintf(fname, "/sys/block/%s/md/%s/%s",
> +	snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/%s/%s",
>  		sra->sys_name, dev?dev->sys_name:"", name);
>  
>  	return stat(fname, &st) == 0;
> @@ -490,10 +494,10 @@ int sysfs_attribute_available(struct mdinfo *sra, struct mdinfo *dev, char *name
>  int sysfs_get_fd(struct mdinfo *sra, struct mdinfo *dev,
>  		       char *name)
>  {
> -	char fname[50];
> +	char fname[MAX_SYSFS_PATH_LEN];
>  	int fd;
>  
> -	sprintf(fname, "/sys/block/%s/md/%s/%s",
> +	snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/%s/%s",
>  		sra->sys_name, dev?dev->sys_name:"", name);
>  	fd = open(fname, O_RDWR);
>  	if (fd < 0)