[PATCH 18/20] arm64: ptrace: handle ptrace_request differently for aarch32 and ilp32

Yury Norov
2017-03-01T19:19:26Z

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: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Chengming Zhou <zhouchengming1@huawei.com>
---
arch/arm64/kernel/ptrace.c | 65 ++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 63 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 09e30a9..81d23ed 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -764,9 +764,11 @@ 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,
@@ -1222,7 +1224,7 @@ 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;
@@ -1299,8 +1301,67 @@ 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_ARM64_ILP32
+#include <asm/signal32_common.h>
+
+static long compat_ilp32_ptrace(struct task_struct *child, compat_long_t request,
+ compat_ulong_t caddr, compat_ulong_t cdata)
+{
+ sigset_t new_set;
+
+ switch (request) {
+ case PTRACE_GETSIGMASK:
+ if (caddr != sizeof(compat_sigset_t))
+ return -EINVAL;
+
+ return put_sigset_t((compat_sigset_t __user *) (u64) cdata,
+ &child->blocked);
+
+ case PTRACE_SETSIGMASK:
+ if (caddr != sizeof(compat_sigset_t))
+ return -EINVAL;
+
+ if (get_sigset_t(&new_set, (compat_sigset_t __user *) (u64) cdata))
+ return -EFAULT;
+
+ sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+ /*
+ * Every thread does recalc_sigpending() after resume, so
+ * retarget_shared_pending() and recalc_sigpending() are not
+ * called here.
+ */
+ spin_lock_irq(&child->sighand->siglock);
+ child->blocked = new_set;
+ spin_unlock_irq(&child->sighand->siglock);
+
+ return 0;
+
+ default:
+ return compat_ptrace_request(child, request, caddr, cdata);
+ }
+}
+
+#else
+#define compat_ilp32_ptrace(child, request, caddr, cdata) (0)
+#endif
+
+#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);
+
+ return compat_ilp32_ptrace(child, request, caddr, cdata);
+}
+#endif
+
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
#ifdef CONFIG_AARCH32_EL0
--
2.7.4