Re: [PATCH] scsi: target: configfs: Remove redundant assignment to ret

From: Bodo Stroesser
Date: Fri Apr 30 2021 - 10:29:20 EST


On 30.04.21 11:23, Jiapeng Chong wrote:
Variable ret is set to '-EINVAL' but this value is never read as it is
overwritten later on, hence it is a redundant assignment and can be
removed.

Clean up the following clang-analyzer warning:

drivers/target/target_core_configfs.c:2037:5: warning: Value stored to
'ret' is never read [clang-analyzer-deadcode.DeadStores].

drivers/target/target_core_configfs.c:1973:5: warning: Value stored to
'ret' is never read [clang-analyzer-deadcode.DeadStores].

drivers/target/target_core_configfs.c:1959:5: warning: Value stored to
'ret' is never read [clang-analyzer-deadcode.DeadStores].

Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
Signed-off-by: Jiapeng Chong <jiapeng.chong@xxxxxxxxxxxxxxxxx>
---
drivers/target/target_core_configfs.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c
index 4b2e493..bda05c3 100644
--- a/drivers/target/target_core_configfs.c
+++ b/drivers/target/target_core_configfs.c
@@ -1956,7 +1956,6 @@ static ssize_t target_pr_res_aptpl_metadata_store(struct config_item *item,
pr_err("APTPL metadata initiator_node="
" exceeds PR_APTPL_MAX_IPORT_LEN: %d\n",
PR_APTPL_MAX_IPORT_LEN);
- ret = -EINVAL;
break;
}
break;
@@ -1970,7 +1969,6 @@ static ssize_t target_pr_res_aptpl_metadata_store(struct config_item *item,
pr_err("APTPL metadata initiator_isid"
"= exceeds PR_REG_ISID_LEN: %d\n",
PR_REG_ISID_LEN);
- ret = -EINVAL;
break;
}
break;
@@ -2034,7 +2032,6 @@ static ssize_t target_pr_res_aptpl_metadata_store(struct config_item *item,
pr_err("APTPL metadata target_node="
" exceeds PR_APTPL_MAX_TPORT_LEN: %d\n",
PR_APTPL_MAX_TPORT_LEN);
- ret = -EINVAL;
break;
}
break;


I don't think storing -EINVAL in ret is wrong. But maybe the "break" in
the next line should better be "goto out"?

AFAICS, the "break" finally leads to calling
core_scsi3_alloc_aptpl_registration () despite a too long string in
i_port, isid or t_port. Is this behaviour intentional?

BTW: why is "initiator_sid" input handled as string?
core_scsi3_alloc_aptpl_registration later calls get_unaligned_be64 for
that string. I don't think this makes sense.

Finally, I think there is a possible memory leak. If the input written
to res_aptpl_metadata for example contains "initiator_sid=xxxxx" more
than once, a previously created string isid ("isid = match_strdup(args)")
is not freed before it is overwritten in the loop. The same is true for
all tokens handled with match_strdup.