From 76b4c33c7f5e353c43ba5e4c7dd8222b13e4c6d1 Mon Sep 17 00:00:00 2001
From: "Dmitry V. Levin" <ldv@altlinux.org>
Date: Fri, 13 May 2016 02:33:33 +0000
Subject: [PATCH] ptrace: decode data argument of PTRACE_PEEKSIGINFO request

The data argument of PTRACE_PEEKSIGINFO request is a pointer
to siginfo_t array.

* printsiginfo.c (print_siginfo_t): New function.
(print_siginfo_array): New mpers printer.
* process.c (SYS_FUNC(ptrace)): Print data argument of
PTRACE_PEEKSIGINFO request using print_siginfo_array.
---
 printsiginfo.c | 18 ++++++++++++++++++
 process.c      |  7 +++++++
 2 files changed, 25 insertions(+)

diff --git a/printsiginfo.c b/printsiginfo.c
index 240fd65e..596d958a 100644
--- a/printsiginfo.c
+++ b/printsiginfo.c
@@ -242,3 +242,21 @@ MPERS_PRINTER_DECL(void, printsiginfo_at)(struct tcb *tcp, long addr)
 	if (!umove_or_printaddr(tcp, addr, &si))
 		printsiginfo(&si, verbose(tcp));
 }
+
+static bool
+print_siginfo_t(struct tcb *tcp, void *elem_buf, size_t elem_size, void *data)
+{
+	const siginfo_t *si = elem_buf;
+
+	printsiginfo(si, verbose(tcp));
+
+	return true;
+}
+
+MPERS_PRINTER_DECL(void, print_siginfo_array)(struct tcb *tcp, unsigned long addr, unsigned long len)
+{
+	siginfo_t si;
+
+	print_array(tcp, addr, len, &si, sizeof(si),
+		    umoven_or_printaddr, print_siginfo_t, 0);
+}
diff --git a/process.c b/process.c
index 19b616d0..3aecf088 100644
--- a/process.c
+++ b/process.c
@@ -212,6 +212,7 @@ SYS_FUNC(ptrace)
 		case PTRACE_GETREGSET:
 		case PTRACE_GETSIGINFO:
 		case PTRACE_GETSIGMASK:
+		case PTRACE_PEEKSIGINFO:
 		case PTRACE_SECCOMP_GET_FILTER:
 			if (verbose(tcp)) {
 				/* print data on exiting syscall */
@@ -245,6 +246,12 @@ SYS_FUNC(ptrace)
 		case PTRACE_GETSIGMASK:
 			print_sigset_addr_len(tcp, data, addr);
 			break;
+		case PTRACE_PEEKSIGINFO:
+			if (syserror(tcp))
+				printaddr(data);
+			else
+				print_siginfo_array(tcp, data, tcp->u_rval);
+			break;
 		case PTRACE_SECCOMP_GET_FILTER:
 			if (syserror(tcp))
 				printaddr(data);
-- 
2.50.1