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Diffstat (limited to 'linux-headers/include/linux/seccomp.h')
-rw-r--r--linux-headers/include/linux/seccomp.h55
1 files changed, 54 insertions, 1 deletions
diff --git a/linux-headers/include/linux/seccomp.h b/linux-headers/include/linux/seccomp.h
index 5d8554e..675b73c 100644
--- a/linux-headers/include/linux/seccomp.h
+++ b/linux-headers/include/linux/seccomp.h
@@ -22,6 +22,7 @@
#define SECCOMP_FILTER_FLAG_LOG (1UL << 1)
#define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2)
#define SECCOMP_FILTER_FLAG_NEW_LISTENER (1UL << 3)
+#define SECCOMP_FILTER_FLAG_TSYNC_ESRCH (1UL << 4)
/*
* All BPF programs must return a 32-bit value.
@@ -76,6 +77,35 @@ struct seccomp_notif {
struct seccomp_data data;
};
+/*
+ * Valid flags for struct seccomp_notif_resp
+ *
+ * Note, the SECCOMP_USER_NOTIF_FLAG_CONTINUE flag must be used with caution!
+ * If set by the process supervising the syscalls of another process the
+ * syscall will continue. This is problematic because of an inherent TOCTOU.
+ * An attacker can exploit the time while the supervised process is waiting on
+ * a response from the supervising process to rewrite syscall arguments which
+ * are passed as pointers of the intercepted syscall.
+ * It should be absolutely clear that this means that the seccomp notifier
+ * _cannot_ be used to implement a security policy! It should only ever be used
+ * in scenarios where a more privileged process supervises the syscalls of a
+ * lesser privileged process to get around kernel-enforced security
+ * restrictions when the privileged process deems this safe. In other words,
+ * in order to continue a syscall the supervising process should be sure that
+ * another security mechanism or the kernel itself will sufficiently block
+ * syscalls if arguments are rewritten to something unsafe.
+ *
+ * Similar precautions should be applied when stacking SECCOMP_RET_USER_NOTIF
+ * or SECCOMP_RET_TRACE. For SECCOMP_RET_USER_NOTIF filters acting on the
+ * same syscall, the most recently added filter takes precedence. This means
+ * that the new SECCOMP_RET_USER_NOTIF filter can override any
+ * SECCOMP_IOCTL_NOTIF_SEND from earlier filters, essentially allowing all
+ * such filtered syscalls to be executed by sending the response
+ * SECCOMP_USER_NOTIF_FLAG_CONTINUE. Note that SECCOMP_RET_TRACE can equally
+ * be overriden by SECCOMP_USER_NOTIF_FLAG_CONTINUE.
+ */
+#define SECCOMP_USER_NOTIF_FLAG_CONTINUE (1UL << 0)
+
struct seccomp_notif_resp {
__u64 id;
__s64 val;
@@ -83,6 +113,25 @@ struct seccomp_notif_resp {
__u32 flags;
};
+/* valid flags for seccomp_notif_addfd */
+#define SECCOMP_ADDFD_FLAG_SETFD (1UL << 0) /* Specify remote fd */
+
+/**
+ * struct seccomp_notif_addfd
+ * @id: The ID of the seccomp notification
+ * @flags: SECCOMP_ADDFD_FLAG_*
+ * @srcfd: The local fd number
+ * @newfd: Optional remote FD number if SETFD option is set, otherwise 0.
+ * @newfd_flags: The O_* flags the remote FD should have applied
+ */
+struct seccomp_notif_addfd {
+ __u64 id;
+ __u32 flags;
+ __u32 srcfd;
+ __u32 newfd;
+ __u32 newfd_flags;
+};
+
#define SECCOMP_IOC_MAGIC '!'
#define SECCOMP_IO(nr) _IO(SECCOMP_IOC_MAGIC, nr)
#define SECCOMP_IOR(nr, type) _IOR(SECCOMP_IOC_MAGIC, nr, type)
@@ -93,5 +142,9 @@ 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)
+/* On success, the return value is the remote process's added fd number */
+#define SECCOMP_IOCTL_NOTIF_ADDFD SECCOMP_IOW(3, \
+ struct seccomp_notif_addfd)
+
#endif /* _LINUX_SECCOMP_H */