[2/4] v4l-utils: fix potential crashing with 32-bit musl

Commit Message

Rosen Penev July 2, 2024, 7:33 p.m. UTC

Under musl, if a format string has an integer followed by %s, a mismatch
between types can cause the second half of the integer to be interpreted
by %s.

Eg: printf("%d %s", 64bittype, string);

will crash, especially on 32-bit big endian.

The reason these are cast to __u64 is because time_t and suseconds_t
are 64-bit under musl, even on 32-bit platforms. __u64 helps avoid
any truncation issues that may or may not arise.

Signed-off-by: Rosen Penev <[e-mail]>
---
 utils/cec-follower/cec-follower.cpp | 2 +-
 utils/libv4l2util/v4l2_driver.c     | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

Patch

diff --git a/utils/cec-follower/cec-follower.cpp b/utils/cec-follower/cec-follower.cpp
index a7481aea..67e0d92b 100644
--- a/utils/cec-follower/cec-follower.cpp
+++ b/utils/cec-follower/cec-follower.cpp
@@ -354,7 +354,7 @@  void print_timers(struct node *node)
 			printf("source: %s, ", source.c_str());
 			if (t.recording_seq)
 				printf("rec-seq: 0x%x, ", t.recording_seq);
-			printf("needs: %ld %s\n", t.duration, "MB."); /* 1MB per second. */
+			printf("needs: %llu %s\n", (__u64)t.duration, "MB."); /* 1MB per second. */
 		}
 		printf("Total media space available for recording: ");
 		if (node->state.media_space_available >= 0)
diff --git a/utils/libv4l2util/v4l2_driver.c b/utils/libv4l2util/v4l2_driver.c
index 6b6366fa..51e97b61 100644
--- a/utils/libv4l2util/v4l2_driver.c
+++ b/utils/libv4l2util/v4l2_driver.c
@@ -174,13 +174,13 @@  static void prt_buf_info(char *name,struct v4l2_buffer *p)
 {
 	struct v4l2_timecode *tc=&p->timecode;
 
-	printf ("%s: %02ld:%02d:%02d.%08ld index=%d, type=%s, "
+	printf ("%s: %02llu:%02d:%02d.%08llu index=%d, type=%s, "
 		"bytesused=%d, flags=0x%08x, "
 		"field=%s, sequence=%d, memory=%s, offset=0x%08x, length=%d\n",
-		name, (p->timestamp.tv_sec/3600),
+		name, (__u64)(p->timestamp.tv_sec/3600),
 		(int)(p->timestamp.tv_sec/60)%60,
 		(int)(p->timestamp.tv_sec%60),
-		p->timestamp.tv_usec,
+		(__u64)p->timestamp.tv_usec,
 		p->index,
 		prt_names(p->type,v4l2_type_names),
 		p->bytesused,p->flags,