[alsa-devel] [PATCH] sound/pci/ice1712: replace strcpy() with scnprintf()

[Joey Pabalinas]

Replace unsafe uses of strcpy() to copy the name
argument into the sid.name buffer with scnprintf()
to guard against possible buffer overflows.

Even though we don't actually care about the return
value in this specific case, scnprintf() is still
preferred over snprintf() due to scnprintf() returning
the much more logical length of what was *actually* encoded
into the destination array instead of returning length
the resulting string *would* be, assuming it all fit
into the destination array as snprintf() does.

Maybe one day someone will use the return value, and
since the behavior is exactly the same apart from the
return value it would be better to account for that
possibility and program defensively.

Signed-off-by: Joey Pabalinas <joeypabalinas at gmail.com>

 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/sound/pci/ice1712/juli.c b/sound/pci/ice1712/juli.c
index 0dbaccf61f33270608..0abacc64168f895d53 100644
--- a/sound/pci/ice1712/juli.c
+++ b/sound/pci/ice1712/juli.c
@@ -26,6 +26,7 @@
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
+#include <linux/kernel.h>
 #include <linux/slab.h>
 #include <sound/core.h>
 #include <sound/tlv.h>
@@ -425,10 +426,9 @@ DECLARE_TLV_DB_SCALE(juli_master_db_scale, -6350, 50, 1);
 static struct snd_kcontrol *ctl_find(struct snd_card *card,
 				     const char *name)
 {
-	struct snd_ctl_elem_id sid;
-	memset(&sid, 0, sizeof(sid));
-	/* FIXME: strcpy is bad. */
-	strcpy(sid.name, name);
+	struct snd_ctl_elem_id sid = {0};
+
+	scnprintf(sid.name, sizeof(sid.name), "%s", name);
 	sid.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 	return snd_ctl_find_id(card, &sid);
 }
diff --git a/sound/pci/ice1712/quartet.c b/sound/pci/ice1712/quartet.c
index d145b5eb7ff86d978d..332f6226548c6a089a 100644
--- a/sound/pci/ice1712/quartet.c
+++ b/sound/pci/ice1712/quartet.c
@@ -25,6 +25,7 @@
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
+#include <linux/kernel.h>
 #include <linux/slab.h>
 #include <sound/core.h>
 #include <sound/tlv.h>
@@ -785,10 +786,9 @@ DECLARE_TLV_DB_SCALE(qtet_master_db_scale, -6350, 50, 1);
 static struct snd_kcontrol *ctl_find(struct snd_card *card,
 				     const char *name)
 {
-	struct snd_ctl_elem_id sid;
-	memset(&sid, 0, sizeof(sid));
-	/* FIXME: strcpy is bad. */
-	strcpy(sid.name, name);
+	struct snd_ctl_elem_id sid = {0};
+
+	scnprintf(sid.name, sizeof(sid.name), "%s", name);
 	sid.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 	return snd_ctl_find_id(card, &sid);
 }
-- 
2.16.2
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