[PATCH] firmware: ti_sci: Fix an off-by-one in ti_sci_debugfs_create()

From: Christophe JAILLET
Date: Sun Oct 29 2023 - 03:52:49 EST


The ending NULL is not taken into account by strncat(), so switch to
strlcat() to correctly compute the size of the available memory when
building 'debug_name'.

Because of the difference in the return type between strncat() and
strlcat(), some code shuffling is needed.

Fixes: aa276781a64a ("firmware: Add basic support for TI System Control Interface (TI-SCI) protocol")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
drivers/firmware/ti_sci.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index 7041befc756a..1036c6b0f3eb 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -181,10 +181,9 @@ static int ti_sci_debugfs_create(struct platform_device *pdev,
/* Setup NULL termination */
info->debug_buffer[info->debug_region_size] = 0;

- info->d = debugfs_create_file(strncat(debug_name, dev_name(dev),
- sizeof(debug_name) -
- sizeof("ti_sci_debug@")),
- 0444, NULL, info, &ti_sci_debug_fops);
+ strlcat(debug_name, dev_name(dev), sizeof(debug_name));
+ info->d = debugfs_create_file(debug_name, 0444, NULL, info,
+ &ti_sci_debug_fops);
if (IS_ERR(info->d))
return PTR_ERR(info->d);

--
2.34.1