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Re: Patch for e2fsprogs and a question about msync()



Svante Signell, le Tue 22 Nov 2011 15:51:18 +0100, a écrit :
> #ifdef MS_SYNC
>         if (tdb->map_ptr) {
>                 tdb_off_t moffset = offset & ~(tdb->page_size-1);
>                 if (msync(moffset + (char *)tdb->map_ptr,
>                           length + (offset - moffset), MS_SYNC) != 0) {
>                         tdb->ecode = TDB_ERR_IO;
>                         TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_transaction:
> msync failed - %s\n",
>                                  strerror(errno)));
>                         return -1;
>                 }
>         }
> #endif

That code should check for ENOSYS and EOPNOTSUPP, as it seems to be fine
with not calling msync at all if MS_SYNC is not available...

> tdb.c:(.text+0x2cc6): warning: warning: msync is not implemented and
> will always fail
> make[1]: Leaving directory
> `.../e2fsprogs-1.42~WIP-2011-11-20.modified/debian/BUILD-STD/e2fsck'
> 
> Consequences when this code is executed??

An error, which has never been spotted before, but probably just by
luck.

> diff -ur e2fsprogs-1.42~WIP-2011-11-20/e2fsck/quota.c e2fsprogs-1.42~WIP-2011-11-20.modified/e2fsck/quota.c
> --- e2fsprogs-1.42~WIP-2011-11-20/e2fsck/quota.c	2011-11-14 16:55:54.000000000 +0100
> +++ e2fsprogs-1.42~WIP-2011-11-20.modified/e2fsck/quota.c	2011-11-22 11:30:13.000000000 +0100
> @@ -24,7 +24,7 @@
>  	ext2_ino_t		ino;
>  	struct ext2_inode	inode;
>  	errcode_t		retval;
> -	char			qf_name[255];
> +	char			*qf_name;
>  
>  	if (ext2fs_read_inode(fs, from_ino, &inode))
>  		return;
> @@ -38,7 +38,7 @@
>  
>  	ext2fs_write_new_inode(fs, to_ino, &inode);
>  	/* unlink the old inode */
> -	quota_get_qf_name(qtype, QFMT_VFS_V1, qf_name);
> +	qf_name = quota_get_qf_name(qtype, QFMT_VFS_V1);
>  	ext2fs_unlink(fs, EXT2_ROOT_INO, qf_name, from_ino, 0);
>  	ext2fs_inode_alloc_stats(fs, from_ino, -1);
>  }

Missing free for qf_name.

> diff -ur e2fsprogs-1.42~WIP-2011-11-20/lib/quota/mkquota.c e2fsprogs-1.42~WIP-2011-11-20.modified/lib/quota/mkquota.c
> --- e2fsprogs-1.42~WIP-2011-11-20/lib/quota/mkquota.c	2011-11-14 17:36:12.000000000 +0100
> +++ e2fsprogs-1.42~WIP-2011-11-20.modified/lib/quota/mkquota.c	2011-11-22 12:53:53.000000000 +0100
> @@ -67,14 +67,15 @@
>   */
>  int quota_file_exists(ext2_filsys fs, int qtype, int fmt)
>  {
> -	char qf_name[256];
> +	char *qf_name;
>  	errcode_t ret;
>  	ext2_ino_t ino;
>  
>  	if (qtype >= MAXQUOTAS)
>  		return -EINVAL;
>  
> -	quota_get_qf_name(qtype, fmt, qf_name);
> +	if ((qf_name = quota_get_qf_name(qtype, fmt)) == NULL)
> +		return 0;
>  
>  	ret = ext2fs_lookup(fs, EXT2_ROOT_INO, qf_name, strlen(qf_name), 0,
>  			    &ino);

Same here.

> diff -ur e2fsprogs-1.42~WIP-2011-11-20/lib/quota/mkquota.h e2fsprogs-1.42~WIP-2011-11-20.modified/lib/quota/mkquota.h
> --- e2fsprogs-1.42~WIP-2011-11-20/lib/quota/mkquota.h	2011-11-14 16:58:28.000000000 +0100
> +++ e2fsprogs-1.42~WIP-2011-11-20.modified/lib/quota/mkquota.h	2011-11-22 12:53:05.000000000 +0100
> @@ -61,7 +61,7 @@
>  void quota_set_sb_inum(ext2_filsys fs, ext2_ino_t ino, int qtype);
>  
>  /* In quotaio.c */
> -const char *quota_get_qf_name(int type, int fmt, char *buf);
> +char *quota_get_qf_name(int type, int fmt);
>  const char *quota_get_qf_path(const char *mntpt, int qtype, int fmt,
>  			      char *path_buf, size_t path_buf_size);
>  
> diff -ur e2fsprogs-1.42~WIP-2011-11-20/lib/quota/quotaio.c e2fsprogs-1.42~WIP-2011-11-20.modified/lib/quota/quotaio.c
> --- e2fsprogs-1.42~WIP-2011-11-20/lib/quota/quotaio.c	2011-11-14 17:37:26.000000000 +0100
> +++ e2fsprogs-1.42~WIP-2011-11-20.modified/lib/quota/quotaio.c	2011-11-22 11:46:36.000000000 +0100
> @@ -52,11 +52,15 @@
>  /**
>   * Creates a quota file name for given type and format.
>   */
> -const char *quota_get_qf_name(int type, int fmt, char *buf)
> +char *quota_get_qf_name(int type, int fmt)
>  {
> -	if (!buf)
> +	int len;
> +	char *buf = NULL;
> +
> +	len = strlen(basenames[fmt]) + 1 + strlen(extensions[type]) + 1;
> +	if( (buf = malloc(len)) == NULL)
>  		return NULL;
> -	snprintf(buf, PATH_MAX, "%s.%s",
> +	snprintf(buf, len, "%s.%s",
>  		 basenames[fmt], extensions[type]);

Looks good.

>  	return buf;
> @@ -66,14 +70,16 @@
>  			      char *path_buf, size_t path_buf_size)
>  {
>  	struct stat	qf_stat;
> -	char qf_name[PATH_MAX] = {0};
> +	char *qf_name = NULL;
>  
>  	if (!mntpt || !path_buf || !path_buf_size)
>  		return NULL;
>  
>  	strncpy(path_buf, mntpt, path_buf_size);
>  	strncat(path_buf, "/", 1);
> -	strncat(path_buf, quota_get_qf_name(qtype, fmt, qf_name),
> +	if ((qf_name = quota_get_qf_name(qtype, fmt)) == NULL)
> +		return NULL;
> +	strncat(path_buf, qf_name,
>  		path_buf_size - strlen(path_buf));
>  
>  	return path_buf;

Missing free here too.

Samuel


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