target: fix ALUA state file path truncation

A sufficiently long Unit Serial string, dbroot path, and/or ALUA target
portal group name may result in truncation of the ALUA state file path
prior to usage. Fix this by using kasprintf() instead.

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 01:39:20 +02:00 committed by Nicholas Bellinger
parent bdc79f0ed1
commit 55435badda
2 changed files with 28 additions and 32 deletions

View File

@ -918,7 +918,7 @@ static int core_alua_update_tpg_primary_metadata(
{
unsigned char *md_buf;
struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
char path[ALUA_METADATA_PATH_LEN];
char *path;
int len, rc;
md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
@ -927,8 +927,6 @@ static int core_alua_update_tpg_primary_metadata(
return -ENOMEM;
}
memset(path, 0, ALUA_METADATA_PATH_LEN);
len = snprintf(md_buf, ALUA_MD_BUF_LEN,
"tg_pt_gp_id=%hu\n"
"alua_access_state=0x%02x\n"
@ -937,11 +935,14 @@ static int core_alua_update_tpg_primary_metadata(
tg_pt_gp->tg_pt_gp_alua_access_state,
tg_pt_gp->tg_pt_gp_alua_access_status);
snprintf(path, ALUA_METADATA_PATH_LEN,
"%s/alua/tpgs_%s/%s", db_root, &wwn->unit_serial[0],
config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
rc = core_alua_write_tpg_metadata(path, md_buf, len);
rc = -ENOMEM;
path = kasprintf(GFP_KERNEL, "%s/alua/tpgs_%s/%s", db_root,
&wwn->unit_serial[0],
config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
if (path) {
rc = core_alua_write_tpg_metadata(path, md_buf, len);
kfree(path);
}
kfree(md_buf);
return rc;
}
@ -1209,7 +1210,7 @@ static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
{
struct se_portal_group *se_tpg = lun->lun_tpg;
unsigned char *md_buf;
char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
char *path;
int len, rc;
mutex_lock(&lun->lun_tg_pt_md_mutex);
@ -1221,28 +1222,32 @@ static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
goto out_unlock;
}
memset(path, 0, ALUA_METADATA_PATH_LEN);
memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
"alua_tg_pt_status=0x%02x\n",
atomic_read(&lun->lun_tg_pt_secondary_offline),
lun->lun_tg_pt_secondary_stat);
snprintf(path, ALUA_METADATA_PATH_LEN, "%s/alua/%s/%s/lun_%llu",
db_root, se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
lun->unpacked_lun);
if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL) {
path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s+%hu/lun_%llu",
db_root, se_tpg->se_tpg_tfo->get_fabric_name(),
se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg),
lun->unpacked_lun);
} else {
path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s/lun_%llu",
db_root, se_tpg->se_tpg_tfo->get_fabric_name(),
se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
lun->unpacked_lun);
}
if (!path) {
rc = -ENOMEM;
goto out_free;
}
rc = core_alua_write_tpg_metadata(path, md_buf, len);
kfree(path);
out_free:
kfree(md_buf);
out_unlock:
mutex_unlock(&lun->lun_tg_pt_md_mutex);
return rc;

View File

@ -71,15 +71,6 @@
*/
#define ALUA_DEFAULT_IMPLICIT_TRANS_SECS 0
#define ALUA_MAX_IMPLICIT_TRANS_SECS 255
/*
* Used by core_alua_update_tpg_primary_metadata() and
* core_alua_update_tpg_secondary_metadata()
*/
#define ALUA_METADATA_PATH_LEN 512
/*
* Used by core_alua_update_tpg_secondary_metadata()
*/
#define ALUA_SECONDARY_METADATA_WWN_LEN 256
/* Used by core_alua_update_tpg_(primary,secondary)_metadata */
#define ALUA_MD_BUF_LEN 1024