Avoid crashes when buffer modification hooks clobber match data
* src/search.c (Freplace_match): Error out if buffer modification hooks triggered by buffer changes in replace_range, upcase-region, and upcase-initials-region clobber the match data needed to be adjusted for the replacement. (Bug#23869)
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13
src/search.c
13
src/search.c
@@ -2684,6 +2684,14 @@ since only regular expressions have distinguished subexpressions. */)
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xfree (substed);
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}
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/* The functions below modify the buffer, so they could trigger
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various modification hooks (see signal_before_change and
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signal_after_change), which might clobber the match data we need
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to adjust after the replacement. If that happens, we error out. */
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ptrdiff_t sub_start = search_regs.start[sub];
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ptrdiff_t sub_end = search_regs.end[sub];
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unsigned num_regs = search_regs.num_regs;
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/* Replace the old text with the new in the cleanest possible way. */
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replace_range (search_regs.start[sub], search_regs.end[sub],
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newtext, 1, 0, 1);
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@@ -2696,6 +2704,11 @@ since only regular expressions have distinguished subexpressions. */)
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Fupcase_initials_region (make_number (search_regs.start[sub]),
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make_number (newpoint));
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if (search_regs.start[sub] != sub_start
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|| search_regs.end[sub] != sub_end
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|| search_regs.num_regs != num_regs)
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error ("Match data clobbered by buffer modification hooks");
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/* Adjust search data for this change. */
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{
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ptrdiff_t oldend = search_regs.end[sub];
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