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

[Richard Fitzgerald <rf@opensource.cirrus.com>]

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: f6bc909e7673 ("firmware: cs_dsp: add driver to support firmware loading on Cirrus Logic DSPs")
---
 drivers/firmware/cirrus/cs_dsp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/cirrus/cs_dsp.c b/drivers/firmware/cirrus/cs_dsp.c
index d2aa0980ed78..0a504a3c4375 100644
--- a/drivers/firmware/cirrus/cs_dsp.c
+++ b/drivers/firmware/cirrus/cs_dsp.c
@@ -1166,7 +1166,7 @@ static inline void cs_dsp_coeff_parse_alg(struct cs_dsp *dsp, const u8 **data,
 
 		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);
 		break;
 	default:
@@ -1199,7 +1199,7 @@ static inline void cs_dsp_coeff_parse_coeff(struct cs_dsp *dsp, const u8 **data,
 		blk->offset = le16_to_cpu(raw->hdr.offset);
 		blk->mem_type = le16_to_cpu(raw->hdr.type);
 		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);
-- 
2.39.2