seccomp: Fix ioctl number for SECCOMP_IOCTL_NOTIF_ID_VALID

[ Upstream commit 47e33c05f9f07cac3de833e531bcac9ae052c7ca ]

When SECCOMP_IOCTL_NOTIF_ID_VALID was first introduced it had the wrong
direction flag set. While this isn't a big deal as nothing currently
enforces these bits in the kernel, it should be defined correctly. Fix
the define and provide support for the old command until it is no longer
needed for backward compatibility.

Fixes: 6a21cc50f0c7 ("seccomp: add a return code to trap to userspace")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/include/uapi/linux/seccomp.h b/include/uapi/linux/seccomp.h
index c1735455bc536b057ae90e359d31237ec6ab91e0..965290f7dcc28241879ebc23b25d437539143ecf 100644 (file)
--- a/include/uapi/linux/seccomp.h
+++ b/include/uapi/linux/seccomp.h
@@ -123,5 +123,6 @@ struct seccomp_notif_resp {
 #define SECCOMP_IOCTL_NOTIF_RECV       SECCOMP_IOWR(0, struct seccomp_notif)
 #define SECCOMP_IOCTL_NOTIF_SEND       SECCOMP_IOWR(1, \
                                                struct seccomp_notif_resp)
-#define SECCOMP_IOCTL_NOTIF_ID_VALID   SECCOMP_IOR(2, __u64)
+#define SECCOMP_IOCTL_NOTIF_ID_VALID   SECCOMP_IOW(2, __u64)
+
 #endif /* _UAPI_LINUX_SECCOMP_H */

diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index d653d8426de90cc6b9a88cc13918b9023fd79383..c461ba99251367287acd31c2c50d0188145cc83e 100644 (file)
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -42,6 +42,14 @@
 #include <linux/uaccess.h>
 #include <linux/anon_inodes.h>
 
+/*
+ * When SECCOMP_IOCTL_NOTIF_ID_VALID was first introduced, it had the
+ * wrong direction flag in the ioctl number. This is the broken one,
+ * which the kernel needs to keep supporting until all userspaces stop
+ * using the wrong command number.
+ */
+#define SECCOMP_IOCTL_NOTIF_ID_VALID_WRONG_DIR SECCOMP_IOR(2, __u64)
+
 enum notify_state {
        SECCOMP_NOTIFY_INIT,
        SECCOMP_NOTIFY_SENT,
@@ -1186,6 +1194,7 @@ static long seccomp_notify_ioctl(struct file *file, unsigned int cmd,
                return seccomp_notify_recv(filter, buf);
        case SECCOMP_IOCTL_NOTIF_SEND:
                return seccomp_notify_send(filter, buf);
+       case SECCOMP_IOCTL_NOTIF_ID_VALID_WRONG_DIR:
        case SECCOMP_IOCTL_NOTIF_ID_VALID:
                return seccomp_notify_id_valid(filter, buf);
        default:

diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 252140a525531463cc2872a2ec3d7500fe06f4e8..ccf276e1388299fe87b535db3a2731c0edd9866a 100644 (file)
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -180,7 +180,7 @@ struct seccomp_metadata {
 #define SECCOMP_IOCTL_NOTIF_RECV       SECCOMP_IOWR(0, struct seccomp_notif)
 #define SECCOMP_IOCTL_NOTIF_SEND       SECCOMP_IOWR(1, \
                                                struct seccomp_notif_resp)
-#define SECCOMP_IOCTL_NOTIF_ID_VALID   SECCOMP_IOR(2, __u64)
+#define SECCOMP_IOCTL_NOTIF_ID_VALID   SECCOMP_IOW(2, __u64)
 
 struct seccomp_notif {
        __u64 id;