[PATCH 2/7] tests: Make sure to not call memcmp with NULL arguments.
Mark Wielaard
mark@klomp.org
Sun May 10 19:53:35 GMT 2020
GCC10 -fanalyzer thinks we are too clever:
elfputzdata.c: In function ‘main’:
elfputzdata.c:178:8: warning: use of possibly-NULL ‘orig_buf’ where
non-null expected [CWE-690]
[-Wanalyzer-possible-null-argument]
178 | && memcmp (orig_buf, d->d_buf, orig_size) == 0)
orig_buf can only be NULL when orig_size is zero, but it might still
be undefined behaviour. So don't try to be too smart and just check
whether we actually have an buffer.
Signed-off-by: Mark Wielaard <mark@klomp.org>
---
tests/ChangeLog | 5 +++++
tests/elfputzdata.c | 21 +++++++++++++--------
2 files changed, 18 insertions(+), 8 deletions(-)
diff --git a/tests/ChangeLog b/tests/ChangeLog
index 301b0fb6..083e138d 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,8 @@
+2020-05-08 Mark Wielaard <mark@klomp.org>
+
+ * elfputzdata.c (main): Explicitly check orig_buf is not NULL
+ before calling memcmp.
+
2020-04-17 Mark Wielaard <mark@klomp.org>
* test-subr.sh (testrun_on_self_obj): New function.
diff --git a/tests/elfputzdata.c b/tests/elfputzdata.c
index 66ab77ba..0d9c020e 100644
--- a/tests/elfputzdata.c
+++ b/tests/elfputzdata.c
@@ -105,14 +105,17 @@ main (int argc, char *argv[])
printf ("Unexpected data size for orig section %zd\n", idx);
return -1;
}
- char *orig_buf = malloc (d->d_size);
- if (orig_size > 0 && orig_buf == NULL)
+ char *orig_buf = NULL;
+ if (orig_size > 0)
{
- printf ("No memory to copy section %zd data\n", idx);
- return -1;
+ orig_buf = malloc (d->d_size);
+ if (orig_buf == NULL)
+ {
+ printf ("No memory to copy section %zd data\n", idx);
+ return -1;
+ }
+ memcpy (orig_buf, d->d_buf, orig_size);
}
- if (orig_size > 0)
- memcpy (orig_buf, d->d_buf, orig_size);
bool forced = false;
if (gnu)
@@ -175,7 +178,8 @@ main (int argc, char *argv[])
}
if (new_size == orig_size
- && memcmp (orig_buf, d->d_buf, orig_size) == 0)
+ && (orig_buf == NULL
+ || memcmp (orig_buf, d->d_buf, orig_size) == 0))
{
printf ("section %zd didn't compress\n", idx);
return -1;
@@ -211,7 +215,8 @@ main (int argc, char *argv[])
return -1;
}
if (newer_size != orig_size
- && memcmp (orig_buf, d->d_buf, orig_size) != 0)
+ && (orig_buf == NULL
+ || memcmp (orig_buf, d->d_buf, orig_size) != 0))
{
printf ("section %zd didn't correctly uncompress\n", idx);
return -1;
--
2.20.1
More information about the Elfutils-devel
mailing list