arm64: ptrace: handle ptrace_request differently for aarch32 and ilp32

maillist inclusion
category: feature
bugzilla: 46790
CVE: NA

Reference: https://github.com/norov/linux/commits/ilp32-5.2

--------------------------------

ILP32 has context-related structures different from both aarch32 and
aarch64/lp64. In this patch compat_arch_ptrace() renamed to
compat_a32_ptrace(), and compat_arch_ptrace() only makes choice between
compat_a32_ptrace() and new compat_ilp32_ptrace() handler.

compat_ilp32_ptrace() calls generic compat_ptrace_request() for all
requests except PTRACE_GETSIGMASK and PTRACE_SETSIGMASK, which need
special handling.
Signed-off-by: NYury Norov <ynorov@caviumnetworks.com>
Signed-off-by: NBamvor Jian Zhang <bamv2005@gmail.com>
Signed-off-by: NYury Norov <ynorov@marvell.com>
Signed-off-by: NXiongfeng Wang <wangxiongfeng2@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>

arch/arm64/kernel/ptrace.c

@@ -1197,9 +1197,11 @@ static const struct user_regset_view user_aarch64_view = {
 	.regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
 };
 
-#ifdef CONFIG_AARCH32_EL0
+#ifdef CONFIG_COMPAT
 #include <linux/compat.h>
+#endif
 
+#ifdef CONFIG_AARCH32_EL0
 enum compat_regset {
 	REGSET_COMPAT_GPR,
 	REGSET_COMPAT_VFP,
@@ -1636,7 +1638,7 @@ static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
 }
 #endif	/* CONFIG_HAVE_HW_BREAKPOINT */
 
-long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
+static long compat_a32_ptrace(struct task_struct *child, compat_long_t request,
 			compat_ulong_t caddr, compat_ulong_t cdata)
 {
 	unsigned long addr = caddr;
@@ -1713,8 +1715,23 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 
 	return ret;
 }
+
+#else
+#define  compat_a32_ptrace(child, request, caddr, cdata)	(0)
 #endif /* CONFIG_AARCH32_EL0 */
 
+#ifdef CONFIG_COMPAT
+long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
+			compat_ulong_t caddr, compat_ulong_t cdata)
+{
+	if (is_a32_compat_task())
+		return compat_a32_ptrace(child, request, caddr, cdata);
+
+	/* ILP32 */
+	return compat_ptrace_request(child, request, caddr, cdata);
+}
+#endif
+
 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 {
 #ifdef CONFIG_AARCH32_EL0