From: Szabolcs Nagy <szabolcs.nagy@arm.com>
Date: Mon, 2 Aug 2021 10:34:56 +0000 (+0100)
Subject: TODO(uapi): cheri: fix clone_args
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fb41a562bf4acfed5c7dc6c0c9b6c2f365d6731a;p=thirdparty%2Fglibc.git

TODO(uapi): cheri: fix clone_args

Current clone_args does not support 128 bit pointers.

TODO: the fix is incomplete (missing clone3 abi checks) and has to be
aligned with purecap clone3 struct layout.
---

diff --git a/sysdeps/unix/sysv/linux/clone-internal.c b/sysdeps/unix/sysv/linux/clone-internal.c
index a71effcbd3c..8550fe9b249 100644
--- a/sysdeps/unix/sysv/linux/clone-internal.c
+++ b/sysdeps/unix/sysv/linux/clone-internal.c
@@ -32,6 +32,7 @@
 #define offsetofend(TYPE, MEMBER) \
   (offsetof (TYPE, MEMBER) + sizeof_field (TYPE, MEMBER))
 
+#ifndef __CHERI_PURE_CAPABILITY__
 _Static_assert (__alignof (struct clone_args) == 8,
 		"__alignof (struct clone_args) != 8");
 _Static_assert (offsetofend (struct clone_args, tls) == CLONE_ARGS_SIZE_VER0,
@@ -42,6 +43,7 @@ _Static_assert (offsetofend (struct clone_args, cgroup) == CLONE_ARGS_SIZE_VER2,
 		"offsetofend (struct clone_args, cgroup) != CLONE_ARGS_SIZE_VER2");
 _Static_assert (sizeof (struct clone_args) == CLONE_ARGS_SIZE_VER2,
 		"sizeof (struct clone_args) != CLONE_ARGS_SIZE_VER2");
+#endif
 
 int
 __clone_internal (struct clone_args *cl_args,
diff --git a/sysdeps/unix/sysv/linux/clone3.h b/sysdeps/unix/sysv/linux/clone3.h
index 889014a6a95..a3fc8deb298 100644
--- a/sysdeps/unix/sysv/linux/clone3.h
+++ b/sysdeps/unix/sysv/linux/clone3.h
@@ -34,6 +34,30 @@ typedef __U64_TYPE __aligned_uint64_t __attribute__ ((__aligned__ (8)));
 
 struct clone_args
 {
+#ifdef __CHERI_PURE_CAPABILITY__
+  /* Flags bit mask.  */
+  __uint64_t flags;
+  /* Where to store PID file descriptor (pid_t *).  */
+  __uintcap_t pidfd;
+  /* Where to store child TID, in child's memory (pid_t *).  */
+  __uintcap_t child_tid;
+  /* Where to store child TID, in parent's memory (int *). */
+  __uintcap_t parent_tid;
+  /* Signal to deliver to parent on child termination */
+  __uint64_t exit_signal;
+  /* The lowest address of stack.  */
+  __uintcap_t stack;
+  /* Size of stack.  */
+  __uint64_t stack_size;
+  /* Location of new TLS.  */
+  __uintcap_t tls;
+  /* Pointer to a pid_t array (since Linux 5.5).  */
+  __uintcap_t set_tid;
+  /* Number of elements in set_tid (since Linux 5.5). */
+  __uint64_t set_tid_size;
+  /* File descriptor for target cgroup of child (since Linux 5.7).  */
+  __uint64_t cgroup;
+#else
   /* Flags bit mask.  */
   __aligned_uint64_t flags;
   /* Where to store PID file descriptor (pid_t *).  */
@@ -56,6 +80,7 @@ struct clone_args
   __aligned_uint64_t set_tid_size;
   /* File descriptor for target cgroup of child (since Linux 5.7).  */
   __aligned_uint64_t cgroup;
+#endif
 };
 
 /* The wrapper of clone3.  */