From: Dmitry V. Levin <ldv@altlinux.org>
Date: Fri, 4 Aug 2017 18:47:59 +0000 (+0000)
Subject: sparc64: do not bail out in get_scno if PTRACE_PEEKTEXT fails
X-Git-Tag: v4.19~184
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9284ce55f077d69d0d9e857d947b38ea667bd07c;p=strace

sparc64: do not bail out in get_scno if PTRACE_PEEKTEXT fails

If the kernel contains commit 84d77d3f06e7e8dea057d10e8ec77ad71f721be3,
PTRACE_PEEKTEXT becames unavailable when the process dumpable flag is
cleared.  As this is not a fatal condition for get_scno, do not bail out
if PTRACE_PEEKTEXT fails.

This condition is triggered and therefore tested by prctl-dumpable test.

* linux/sparc64/get_scno.c (arch_get_scno): Do not bail out
if PTRACE_PEEKTEXT fails.
---

diff --git a/linux/sparc64/get_scno.c b/linux/sparc64/get_scno.c
index 4abe2a1f..81a3aa93 100644
--- a/linux/sparc64/get_scno.c
+++ b/linux/sparc64/get_scno.c
@@ -6,18 +6,18 @@ arch_get_scno(struct tcb *tcp)
 	unsigned long trap;
 	errno = 0;
 	trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (void *) sparc_regs.tpc, 0);
-	if (errno)
-		return -1;
-	trap >>= 32;
-	switch (trap) {
-	case 0x91d02010:
-		/* Linux/SPARC syscall trap. */
-		update_personality(tcp, 1);
-		break;
-	case 0x91d0206d:
-		/* Linux/SPARC64 syscall trap. */
-		update_personality(tcp, 0);
-		break;
+	if (errno == 0) {
+		trap >>= 32;
+		switch (trap) {
+		case 0x91d02010:
+			/* Linux/SPARC syscall trap. */
+			update_personality(tcp, 1);
+			break;
+		case 0x91d0206d:
+			/* Linux/SPARC64 syscall trap. */
+			update_personality(tcp, 0);
+			break;
+		}
 	}
 
 	tcp->scno = sparc_regs.u_regs[U_REG_G1];