On 3/10/26 3:21 AM, Sun Jian wrote:
read_iter() always NUL-terminated at the end of the buffer, so strstr()
could scan uninitialized stack bytes on short reads. Terminate at len and
use O_RDONLY.
Signed-off-by: Sun Jian <[email protected]>
---
tools/testing/selftests/bpf/prog_tests/test_bpffs.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/test_bpffs.c
b/tools/testing/selftests/bpf/prog_tests/test_bpffs.c
index ea933fd151c3..e8021ff0581c 100644
--- a/tools/testing/selftests/bpf/prog_tests/test_bpffs.c
+++ b/tools/testing/selftests/bpf/prog_tests/test_bpffs.c
@@ -17,11 +17,11 @@ static int read_iter(char *file)
char buf[1024];
int fd, len;
- fd = open(file, 0);
+ fd = open(file, O_RDONLY);
if (fd < 0)
return -1;
- while ((len = read(fd, buf, sizeof(buf))) > 0) {
- buf[sizeof(buf) - 1] = '\0';
+ while ((len = read(fd, buf, sizeof(buf) - 1)) > 0) {
+ buf[len] = '\0';
if (strstr(buf, "iter")) {
close(fd);
return 0;
The change here is unnecessary. Typically /sys/fs/bpf/ should be mounted
earlier and the 'iter' should appear with early prog/map id's. This ensure
'iter' will be discovered earlier. If you have an issue for this, fix
your setup.
base-commit: 1f318b96cc84d7c2ab792fcc0bfd42a7ca890681
