From: Jon Doron <jond@xxxxxx>
When running rootless with special capabilities like:
FOWNER / DAC_OVERRIDE / DAC_READ_SEARCH
The access API will not make the proper check if there is really
access to a file or not.
Signed-off-by: Jon Doron <jond@xxxxxx>
---
tools/lib/bpf/libbpf.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 50d41815f431..df804fd65493 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -875,8 +875,9 @@ __u32 get_kernel_version(void)
const char *ubuntu_kver_file = "/proc/version_signature";
__u32 major, minor, patch;
struct utsname info;
+ struct stat sb;
- if (access(ubuntu_kver_file, R_OK) == 0) {
+ if (stat(ubuntu_kver_file, &sb) == 0) {
FILE *f;
f = fopen(ubuntu_kver_file, "r");
@@ -9877,9 +9878,10 @@ static int append_to_file(const char *file, const char *fmt, ...)
static bool use_debugfs(void)
{
static int has_debugfs = -1;
+ struct stat sb;
if (has_debugfs < 0)
- has_debugfs = access(DEBUGFS, F_OK) == 0;
+ has_debugfs = stat(DEBUGFS, &sb) == 0;
return has_debugfs == 1;
}
--
2.37.3
