RT #75812: apply get magic before checking flags, PVX

The code was checking flags with applying any get magic, so when a
match was doing putting a numeric string into $1, none of the flags
checked were set, so producing the "non-numeric process ID" error.

2 files changed, 14 insertions, 4 deletions

diff --git a/doio.c b/doio.c
index 98861af131..06f2d3d4c3 100644
--- a/doio.c
+++ b/doio.c
@@ -1721,9 +1721,10 @@ nothing in the core.
 	    while (++mark <= sp) {
 		I32 proc;
 		register unsigned long int __vmssts;
+		SvGETMAGIC(*mark);
 		if (!(SvIOK(*mark) || SvNOK(*mark) || looks_like_number(*mark)))
 		    Perl_croak(aTHX_ "Can't kill a non-numeric process ID");
-		proc = SvIV(*mark);
+		proc = SvIV_nomg(*mark);
 		APPLY_TAINT_PROPER();
 		if (!((__vmssts = sys$delprc(&proc,0)) & 1)) {
 		    tot--;
@@ -1748,9 +1749,10 @@ nothing in the core.
 	    val = -val;
 	    while (++mark <= sp) {
 		I32 proc;
+		SvGETMAGIC(*mark);
 		if (!(SvIOK(*mark) || SvNOK(*mark) || looks_like_number(*mark)))
 		    Perl_croak(aTHX_ "Can't kill a non-numeric process ID");
-		proc = SvIV(*mark);
+		proc = SvIV_nomg(*mark);
 		APPLY_TAINT_PROPER();
 #ifdef HAS_KILLPG
 		if (PerlProc_killpg(proc,val))	/* BSD */
@@ -1763,9 +1765,10 @@ nothing in the core.
 	else {
 	    while (++mark <= sp) {
 		I32 proc;
+		SvGETMAGIC(*mark);
 		if (!(SvIOK(*mark) || SvNOK(*mark) || looks_like_number(*mark)))
 		    Perl_croak(aTHX_ "Can't kill a non-numeric process ID");
-		proc = SvIV(*mark);
+		proc = SvIV_nomg(*mark);
 		APPLY_TAINT_PROPER();
 		if (PerlProc_kill(proc, val))
 		    tot--;
diff --git a/t/op/kill0.t b/t/op/kill0.t
index eadf15dc36..d3ef8f7799 100644
--- a/t/op/kill0.t
+++ b/t/op/kill0.t
@@ -14,7 +14,7 @@ BEGIN {
 
 use strict;
 
-plan tests => 5;
+plan tests => 6;
 
 ok( kill(0, $$), 'kill(0, $pid) returns true if $pid exists' );
 
@@ -43,3 +43,10 @@ for my $case ( @bad_pids ) {
   like( $@, qr/^Can't kill a non-numeric process ID/, "dies killing $name pid");
 }
 
+# Verify that killing a magic variable containing a number doesn't
+# trigger the above
+{
+  my $x = $$ . " ";
+  $x =~ /(\d+)/;
+  ok(eval { kill 0, $1 }, "can kill a number string in a magic variable");
+}