target/ppc/kvm: Skip current and parent directories in kvmppc_find_cpu_dt

Some systems have /proc/device-tree/cpus/../clock-frequency. However,
this is not the expected path for a CPU device tree directory.

Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220712210810.35514-1-muriloo@linux.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
index 6eed466f8096eead56bd0f7b3b1d04777f745fc0..466d0d2f4c85fc4df5b13b8dd05757c91b26af91 100644 (file)
--- a/target/ppc/kvm.c
+++ b/target/ppc/kvm.c
@@ -1877,6 +1877,12 @@ static int kvmppc_find_cpu_dt(char *buf, int buf_len)
     buf[0] = '\0';
     while ((dirp = readdir(dp)) != NULL) {
         FILE *f;
+
+        /* Don't accidentally read from the current and parent directories */
+        if (strcmp(dirp->d_name, ".") == 0 || strcmp(dirp->d_name, "..") == 0) {
+            continue;
+        }
+
         snprintf(buf, buf_len, "%s%s/clock-frequency", PROC_DEVTREE_CPU,
                  dirp->d_name);
         f = fopen(buf, "r");