firmware: cs_dsp: Use strnlen() on name fields in V1 wmfw files

jira LE-3201
cve CVE-2024-41056
Rebuild_History Non-Buildable kernel-rt-4.18.0-553.22.1.rt7.363.el8_10
commit-author Richard Fitzgerald <rf@opensource.cirrus.com>
commit 680e126

Use strnlen() instead of strlen() on the algorithm and coefficient name
string arrays in V1 wmfw files.

In V1 wmfw files the name is a NUL-terminated string in a fixed-size
array. cs_dsp should protect against overrunning the array if the NUL
terminator is missing.

	Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: f6bc909 ("firmware: cs_dsp: add driver to support firmware loading on Cirrus Logic DSPs")
Link: https://patch.msgid.link/20240708144855.385332-1-rf@opensource.cirrus.com
	Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 680e126)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

Author: PlaidCat

drivers/firmware/cirrus/cs_dsp.c

@@ -1128,7 +1128,7 @@ static int cs_dsp_coeff_parse_alg(struct cs_dsp *dsp,
 
 		blk->id = le32_to_cpu(raw->id);
 		blk->name = raw->name;
-		blk->name_len = strlen(raw->name);
+		blk->name_len = strnlen(raw->name, ARRAY_SIZE(raw->name));
 		blk->ncoeff = le32_to_cpu(raw->ncoeff);
 
 		pos = sizeof(*raw);
@@ -1204,7 +1204,7 @@ static int cs_dsp_coeff_parse_coeff(struct cs_dsp *dsp,
 			return -EOVERFLOW;
 
 		blk->name = raw->name;
-		blk->name_len = strlen(raw->name);
+		blk->name_len = strnlen(raw->name, ARRAY_SIZE(raw->name));
 		blk->ctl_type = le16_to_cpu(raw->ctl_type);
 		blk->flags = le16_to_cpu(raw->flags);
 		blk->len = le32_to_cpu(raw->len);