From: Dmitry V. Levin <ldv@altlinux.org>
Date: Thu, 12 May 2016 15:10:41 +0000 (+0000)
Subject: ptrace: do not print addr and data arguments of PTRACE_ATTACH-like requests
X-Git-Tag: v4.12~181
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=91bd125f5370ca380a697ac156c06f968c311a33;p=strace

ptrace: do not print addr and data arguments of PTRACE_ATTACH-like requests

As kernel ignores addr and data arguments of PTRACE_ATTACH,
PTRACE_INTERRUPT, PTRACE_KILL, and PTRACE_LISTEN request,
we do not print them either.

* process.c (SYS_FUNC(ptrace)): After printing pid argument, return
RVAL_DECODED if request is one of PTRACE_ATTACH, PTRACE_INTERRUPT,
PTRACE_KILL, or PTRACE_LISTEN.
---

diff --git a/process.c b/process.c
index f53c12e0..620cc1f4 100644
--- a/process.c
+++ b/process.c
@@ -97,24 +97,34 @@ SYS_FUNC(ptrace)
 		}
 
 		/* pid */
-		tprintf(", %d, ", pid);
+		tprintf(", %d", pid);
 
 		/* addr */
 		switch (request) {
+		case PTRACE_ATTACH:
+		case PTRACE_INTERRUPT:
+		case PTRACE_KILL:
+		case PTRACE_LISTEN:
+			/* addr and data are ignored */
+			return RVAL_DECODED;
 		case PTRACE_PEEKUSER:
 		case PTRACE_POKEUSER:
+			tprints(", ");
 			print_user_offset_addr(addr);
 			break;
 		case PTRACE_GETREGSET:
 		case PTRACE_SETREGSET:
+			tprints(", ");
 			printxval(nt_descriptor_types, addr, "NT_???");
 			break;
 		default:
+			tprints(", ");
 			printaddr(addr);
 		}
 
 		tprints(", ");
 
+		/* data */
 		switch (request) {
 #ifndef IA64
 		case PTRACE_PEEKDATA: