[PATCH 4/8] mtd-utils: Fix some simple cases of uninitialized value reads

[David Oberhollenzer <david.oberhollenzer@xxxxxxxxxxxxx>]

This patch modifies the internal helpers to read and parse integers
from sysfs files by initializing them first and removes turns an
obscure "a = open(...) if (a >= 0) {...} if (a == -1) {...}" inside
recv_image into a more straight forward if/else branch.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@xxxxxxxxxxxxx>
---
 lib/libmtd.c            | 2 ++
 lib/libubi.c            | 1 +
 misc-utils/recv_image.c | 3 +--
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/libmtd.c b/lib/libmtd.c
index 564e5c0..9d8d0e8 100644
--- a/lib/libmtd.c
+++ b/lib/libmtd.c
@@ -217,6 +217,7 @@ static int read_hex_ll(const char *file, long long *value)
 	}
 	buf[rd] = '\0';
 
+	*value = 0;
 	if (sscanf(buf, "%llx\n", value) != 1) {
 		errmsg("cannot read integer from \"%s\"\n", file);
 		errno = EINVAL;
@@ -269,6 +270,7 @@ static int read_pos_ll(const char *file, long long *value)
 		goto out_error;
 	}
 
+	*value = 0;
 	if (sscanf(buf, "%lld\n", value) != 1) {
 		errmsg("cannot read integer from \"%s\"\n", file);
 		errno = EINVAL;
diff --git a/lib/libubi.c b/lib/libubi.c
index 4322a19..aaeeb38 100644
--- a/lib/libubi.c
+++ b/lib/libubi.c
@@ -94,6 +94,7 @@ static int read_positive_ll(const char *file, long long *value)
 	}
 	buf[rd] = '\0';
 
+	*value = 0;
 	if (sscanf(buf, "%lld\n", value) != 1) {
 		errmsg("cannot read integer from \"%s\"\n", file);
 		errno = EINVAL;
diff --git a/misc-utils/recv_image.c b/misc-utils/recv_image.c
index 7f6662b..eeaa2e2 100644
--- a/misc-utils/recv_image.c
+++ b/misc-utils/recv_image.c
@@ -81,8 +81,7 @@ int main(int argc, char **argv)
 			printf("Receive to MTD device %s with erasesize %d\n",
 			       argv[3], meminfo.erasesize);
 		}
-	}
-	if (flfd == -1) {
+	} else {
 		/* Try again, as if it's a file */
 		flfd = open(argv[3], O_CREAT|O_TRUNC|O_RDWR, 0644);
 		if (flfd < 0) {
-- 
2.24.1


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