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From: Julien Ramseier <j.ramseier@gmail.com>
To: musl@lists.openwall.com
Subject: [musl] [PATCH] vfscanf: fix use of uninitialized variable
Date: Wed, 1 Jul 2020 15:12:14 +0200	[thread overview]
Message-ID: <E8B0FA07-16BD-490D-B48A-AC062A8F4A52@gmail.com> (raw)

vfscanf() may use the variable 'alloc' uninitialized when taking the branch
introduced by recent commit b287cd745c2243f8e5114331763a5a9813b5f6ee.

Spotted by clang:

../lib/libc/src/stdio/vfscanf.c:80:6: warning: variable 'alloc' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
        if (!f->rpos) goto input_fail;
            ^~~~~~~~
../lib/libc/src/stdio/vfscanf.c:330:7: note: uninitialized use occurs here
                if (alloc) {
                    ^~~~~

---
 src/stdio/vfscanf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/stdio/vfscanf.c b/src/stdio/vfscanf.c
index b5ebc16e..b78a374d 100644
--- a/src/stdio/vfscanf.c
+++ b/src/stdio/vfscanf.c
@@ -57,7 +57,7 @@ int vfscanf(FILE *restrict f, const char *restrict fmt, va_list ap)
 {
 	int width;
 	int size;
-	int alloc;
+	int alloc = 0;
 	int base;
 	const unsigned char *p;
 	int c, t;
-- 
2.23.0

             reply	other threads:[~2020-07-01 13:12 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-01 13:12 Julien Ramseier [this message]
2020-07-06 22:00 ` Rich Felker

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