From: Timo Sirainen <tss@iki.fi>
Date: Wed, 13 May 2015 16:24:55 +0000 (+0300)
Subject: mbox: Fixed corruption in some usage patterns.
X-Git-Tag: 2.2.17~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fcc2880f80385e29924aa926a1eefc5f0f41fa45;p=thirdparty%2Fdovecot%2Fcore.git

mbox: Fixed corruption in some usage patterns.
Something like:
 - first mail is being expunged
 - other mails are being rewritten and they get their space from the
   expunged mail
 - there's not enough space for the last mail to get space
 - we add more space
 - we'll now need to use up the space. We can't just decide to mark the
   mails dirty.
---

diff --git a/src/lib-storage/index/mbox/mbox-sync.c b/src/lib-storage/index/mbox/mbox-sync.c
index cf99716f10..c9f4883349 100644
--- a/src/lib-storage/index/mbox/mbox-sync.c
+++ b/src/lib-storage/index/mbox/mbox-sync.c
@@ -689,8 +689,10 @@ static int mbox_sync_handle_header(struct mbox_sync_mail_context *mail_ctx)
 		}
 	} else if (mail_ctx->need_rewrite) {
 		mbox_sync_update_header(mail_ctx);
-		if (sync_ctx->delay_writes) {
-			/* mark it dirty and do it later */
+		if (sync_ctx->delay_writes && sync_ctx->need_space_seq == 0) {
+			/* mark it dirty and do it later. we can't do this
+			   if we're in the middle of rewriting acquiring more
+			   space. */
 			mail_ctx->dirty = TRUE;
 			return 0;
 		}