target: fix PR state file path truncation

If an LIO backstore is configured with a sufficiently long Unit Serial
string, alongside a similarly long dbroot path, then a truncated
Persistent Reservation APTPL state file path will be used. This
truncation can unintentionally lead to two LUs with differing serial
numbers sharing PR state file.

Fixes: fdddf93226 ("target: use new "dbroot" target attribute")
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
David Disseldorp 2017-10-19 01:39:19 +02:00 коммит произвёл Nicholas Bellinger
Родитель 1ae01724ae
Коммит bdc79f0ed1
1 изменённых файлов: 7 добавлений и 9 удалений

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@ -1973,24 +1973,21 @@ static int __core_scsi3_write_aptpl_to_file(
struct t10_wwn *wwn = &dev->t10_wwn;
struct file *file;
int flags = O_RDWR | O_CREAT | O_TRUNC;
char path[512];
char *path;
u32 pr_aptpl_buf_len;
int ret;
loff_t pos = 0;
memset(path, 0, 512);
path = kasprintf(GFP_KERNEL, "%s/pr/aptpl_%s", db_root,
&wwn->unit_serial[0]);
if (!path)
return -ENOMEM;
if (strlen(&wwn->unit_serial[0]) >= 512) {
pr_err("WWN value for struct se_device does not fit"
" into path buffer\n");
return -EMSGSIZE;
}
snprintf(path, 512, "%s/pr/aptpl_%s", db_root, &wwn->unit_serial[0]);
file = filp_open(path, flags, 0600);
if (IS_ERR(file)) {
pr_err("filp_open(%s) for APTPL metadata"
" failed\n", path);
kfree(path);
return PTR_ERR(file);
}
@ -2001,6 +1998,7 @@ static int __core_scsi3_write_aptpl_to_file(
if (ret < 0)
pr_debug("Error writing APTPL metadata file: %s\n", path);
fput(file);
kfree(path);
return (ret < 0) ? -EIO : 0;
}