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Change 33937: [perl #54758] Perl 5.10 memory corruption

From:
Dave Mitchell
Date:
May 26, 2008 17:15
Subject:
Change 33937: [perl #54758] Perl 5.10 memory corruption
Change 33937 by davem@davem-pigeon on 2008/05/27 00:12:52

	[perl #54758] Perl 5.10 memory corruption
	When @a = sort @a is pessimised if @a has magic,
	growing the stack requires various pointers to be reset in case
	the stack gets reallocated.

Affected files ...

... //depot/perl/pp_sort.c#79 edit

Differences ...

==== //depot/perl/pp_sort.c#79 (text) ====
Index: perl/pp_sort.c
--- perl/pp_sort.c#78~33448~	2008-03-06 05:29:56.000000000 -0800
+++ perl/pp_sort.c	2008-05-26 17:12:52.000000000 -0700
@@ -1557,11 +1557,12 @@
 	max = AvFILL(av) + 1;
 	if (SvMAGICAL(av)) {
 	    MEXTEND(SP, max);
-	    p2 = SP;
 	    for (i=0; i < max; i++) {
 		SV **svp = av_fetch(av, i, FALSE);
 		*SP++ = (svp) ? *svp : NULL;
 	    }
+	    SP--;
+	    p1 = p2 = SP - (max-1);
 	}
 	else {
 	    if (SvREADONLY(av))
@@ -1717,7 +1718,7 @@
 	SvREADONLY_off(av);
     else if (av && !sorting_av) {
 	/* simulate pp_aassign of tied AV */
-	SV** const base = ORIGMARK+1;
+	SV** const base = MARK+1;
 	for (i=0; i < max; i++) {
 	    base[i] = newSVsv(base[i]);
 	}
End of Patch.



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