iio: Fix a buffer overflow in iio_utils.h example code
This was originally reported by Craig Markwardt on Zubair Lutfullah's
blog and Zubair forwarded it to linux-iio@vger.kernel.org. No email
address known.
The code first counted the number of enabled channels, then created an
array to hold information about them. The code that filled this array then
stored whether a given element was enabled inside the array. Curriously
this element was never used. Craig's patch added a local temporary variable
to avoid the buffer overrun. Jonathan then removed the original enabled
element of the structure as it was not needed at all.
Signed-off-by: Zubair Lutfullah <zubair.lutfullah@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/staging/iio/Documentation/iio_utils.h b/drivers/staging/iio/Documentation/iio_utils.h
index 35154d6..c9fedb7 100644
--- a/drivers/staging/iio/Documentation/iio_utils.h
+++ b/drivers/staging/iio/Documentation/iio_utils.h
@@ -77,7 +77,6 @@
uint64_t mask;
unsigned be;
unsigned is_signed;
- unsigned enabled;
unsigned location;
};
@@ -335,6 +334,7 @@
while (ent = readdir(dp), ent != NULL) {
if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
"_en") == 0) {
+ int current_enabled = 0;
current = &(*ci_array)[count++];
ret = asprintf(&filename,
"%s/%s", scan_el_dir, ent->d_name);
@@ -350,10 +350,10 @@
ret = -errno;
goto error_cleanup_array;
}
- fscanf(sysfsfp, "%u", ¤t->enabled);
+ fscanf(sysfsfp, "%u", ¤t_enabled);
fclose(sysfsfp);
- if (!current->enabled) {
+ if (!current_enabled) {
free(filename);
count--;
continue;