shells/bash: fix nested brace expansion, from upstream

This fixes a reported problem in sysutils/neofetch.

shells/bash/Makefile

@@ -2,6 +2,7 @@ COMMENT=	GNU Bourne Again Shell
 
 DISTNAME=	bash-5.2
 PKGNAME=	bash-5.2.2
+REVISION=	0
 CATEGORIES=	shells
 HOMEPAGE=	https://www.gnu.org/software/bash/
 

shells/bash/patches/patch-subst_c

@@ -0,0 +1,42 @@
+Fix nested brace expansion.
+https://lists.gnu.org/archive/html/bug-bash/2022-10/txtAAVHexDehk.txt
+
+Index: subst.c
+--- subst.c.orig
++++ subst.c
+@@ -1798,6 +1798,9 @@ extract_heredoc_dolbrace_string (string, sindex, quote
+   return (result);
+ }
+ 
++#define PARAMEXPNEST_MAX	32	// for now
++static int dbstate[PARAMEXPNEST_MAX];
++
+ /* Extract a parameter expansion expression within ${ and } from STRING.
+    Obey the Posix.2 rules for finding the ending `}': count braces while
+    skipping over enclosed quoted strings and command substitutions.
+@@ -1828,6 +1831,8 @@ extract_dollar_brace_string (string, sindex, quoted, f
+   if (quoted == Q_HERE_DOCUMENT && dolbrace_state == DOLBRACE_QUOTE && (flags & SX_NOALLOC) == 0)
+     return (extract_heredoc_dolbrace_string (string, sindex, quoted, flags));
+ 
++  dbstate[0] = dolbrace_state;
++
+   pass_character = 0;
+   nesting_level = 1;
+   slen = strlen (string + *sindex) + *sindex;
+@@ -1852,6 +1857,8 @@ extract_dollar_brace_string (string, sindex, quoted, f
+ 
+       if (string[i] == '$' && string[i+1] == LBRACE)
+ 	{
++	  if (nesting_level < PARAMEXPNEST_MAX)
++	    dbstate[nesting_level] = dolbrace_state;
+ 	  nesting_level++;
+ 	  i += 2;
+ 	  if (dolbrace_state == DOLBRACE_QUOTE || dolbrace_state == DOLBRACE_WORD)
+@@ -1864,6 +1871,7 @@ extract_dollar_brace_string (string, sindex, quoted, f
+ 	  nesting_level--;
+ 	  if (nesting_level == 0)
+ 	    break;
++	  dolbrace_state = (nesting_level < PARAMEXPNEST_MAX) ? dbstate[nesting_level] : dbstate[0];	/* Guess using initial state */
+ 	  i++;
+ 	  continue;
+ 	}