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commit dca565886b5e8bd7966e15f0ca42ee5cff686673
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Author: DJ Delorie <dj@redhat.com>
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Date:   Thu Feb 25 16:08:21 2021 -0500
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    nscd: Fix double free in netgroupcache [BZ #27462]
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    In commit 745664bd798ec8fd50438605948eea594179fba1 a use-after-free
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    was fixed, but this led to an occasional double-free.  This patch
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    tracks the "live" allocation better.
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    Tested manually by a third party.
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    Related: RHBZ 1927877
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    Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
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    Reviewed-by: Carlos O'Donell <carlos@redhat.com>
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diff --git a/nscd/netgroupcache.c b/nscd/netgroupcache.c
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index f521df824102bbca..5ee4413ef9384ec9 100644
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--- a/nscd/netgroupcache.c
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+++ b/nscd/netgroupcache.c
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@@ -248,7 +248,7 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
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 					     : NULL);
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 				    ndomain = (ndomain ? newbuf + ndomaindiff
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 					       : NULL);
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-				    buffer = newbuf;
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+				    *tofreep = buffer = newbuf;
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 				  }
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 				nhost = memcpy (buffer + bufused,
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@@ -319,7 +319,7 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
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 		    else if (status == NSS_STATUS_TRYAGAIN && e == ERANGE)
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 		      {
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 			buflen *= 2;
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-			buffer = xrealloc (buffer, buflen);
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+			*tofreep = buffer = xrealloc (buffer, buflen);
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 		      }
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 		    else if (status == NSS_STATUS_RETURN
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 			     || status == NSS_STATUS_NOTFOUND