From: Timo Sirainen <tss@iki.fi>
Date: Fri, 4 Dec 2015 09:38:00 +0000 (+0200)
Subject: lib-index: mail_transaction_log_file_map() didn't properly check start_offset
X-Git-Tag: 2.2.20~25
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6e1a910370a55db38b97e12026cd69b2dab38bef;p=thirdparty%2Fdovecot%2Fcore.git

lib-index: mail_transaction_log_file_map() didn't properly check start_offset
If it was too high, it still returned successful mapping. This could have
caused an assert-crash later on when the start_offset was actually attempted
to be used.
---

diff --git a/src/lib-index/mail-transaction-log-file.c b/src/lib-index/mail-transaction-log-file.c
index eea8e59a62..1b390c2c20 100644
--- a/src/lib-index/mail-transaction-log-file.c
+++ b/src/lib-index/mail-transaction-log-file.c
@@ -1681,6 +1681,7 @@ int mail_transaction_log_file_map(struct mail_transaction_log_file *file,
 				  uoff_t start_offset, uoff_t end_offset)
 {
 	struct mail_index *index = file->log->index;
+	uoff_t map_start_offset = start_offset;
 	size_t size;
 	int ret;
 
@@ -1736,14 +1737,14 @@ int mail_transaction_log_file_map(struct mail_transaction_log_file *file,
 		/* although we could just skip over the unwanted data, we have
 		   to sync everything so that modseqs are calculated
 		   correctly */
-		start_offset = file->sync_offset;
+		map_start_offset = file->sync_offset;
 	}
 
 	if ((file->log->index->flags & MAIL_INDEX_OPEN_FLAG_MMAP_DISABLE) == 0)
-		ret = mail_transaction_log_file_map_mmap(file, start_offset);
+		ret = mail_transaction_log_file_map_mmap(file, map_start_offset);
 	else {
 		mail_transaction_log_file_munmap(file);
-		ret = mail_transaction_log_file_read(file, start_offset, FALSE);
+		ret = mail_transaction_log_file_read(file, map_start_offset, FALSE);
 	}
 
 	i_assert(file->buffer == NULL || file->mmap_base != NULL ||