From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Sun, 5 Feb 2023 18:47:08 +0000 (+0200)
Subject: lib-index: Don't update max_tail_offset if write to dovecot.index.log fails
X-Git-Tag: 2.3.21~63
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=830a7db7c030dc831ba11873b09a1c937f095ab3;p=thirdparty%2Fdovecot%2Fcore.git

lib-index: Don't update max_tail_offset if write to dovecot.index.log fails

The max_tail_offset didn't actually increase in that situation.
This fixes wrongly updating mail_index_header.log_file_tail_offset after
write to dovecot.index.log failed (due to out of disk space), which in
turn can cause some unexpected errors.
---

diff --git a/src/lib-index/mail-transaction-log-append.c b/src/lib-index/mail-transaction-log-append.c
index 662f72a9f9..7ed2984deb 100644
--- a/src/lib-index/mail-transaction-log-append.c
+++ b/src/lib-index/mail-transaction-log-append.c
@@ -84,10 +84,6 @@ static int log_buffer_write(struct mail_transaction_log_append_ctx *ctx)
 		return log_buffer_move_to_memory(ctx);
 	}
 
-	i_assert(!ctx->sync_includes_this ||
-		 file->sync_offset + ctx->output->used ==
-		 file->max_tail_offset);
-
 	if ((ctx->want_fsync &&
 	     file->log->index->set.fsync_mode != FSYNC_MODE_NEVER) ||
 	    file->log->index->set.fsync_mode == FSYNC_MODE_ALWAYS) {
@@ -110,6 +106,8 @@ static int log_buffer_write(struct mail_transaction_log_append_ctx *ctx)
 			      ctx->output->used);
 	}
 	file->sync_offset += ctx->output->used;
+	if (ctx->sync_includes_this)
+		file->max_tail_offset = file->sync_offset;
 	return 0;
 }
 
@@ -123,6 +121,7 @@ log_append_sync_offset_if_needed(struct mail_transaction_log_append_ctx *ctx)
 	buffer_t buf;
 	unsigned char update_data[sizeof(*u) + sizeof(offset)];
 
+	offset = file->max_tail_offset;
 	if (!ctx->index_sync_transaction) {
 		/* this is a non-syncing transaction. update the tail offset
 		   only if we're already writing something else to transaction
@@ -148,7 +147,7 @@ log_append_sync_offset_if_needed(struct mail_transaction_log_append_ctx *ctx)
 		   can't rely on this. then write non-changed offset + check
 		   real offset + rewrite the new offset if other transactions
 		   weren't written in the middle */
-		file->max_tail_offset += ctx->output->used +
+		offset = file->max_tail_offset + ctx->output->used +
 			sizeof(*hdr) + sizeof(*u) + sizeof(offset);
 		ctx->sync_includes_this = TRUE;
 	} else {
@@ -156,7 +155,6 @@ log_append_sync_offset_if_needed(struct mail_transaction_log_append_ctx *ctx)
 		   we may need to update the tail offset even if we don't have
 		   anything else to do. */
 	}
-	offset = file->max_tail_offset;
 
 	if (file->last_read_hdr_tail_offset == offset)
 		return;