From 62b8b657d9d07844b8b72d21df5b8e66ee84ac43 Mon Sep 17 00:00:00 2001
From: Vsevolod Stakhov <vsevolod@highsecure.ru>
Date: Fri, 29 Jul 2016 13:54:58 +0100
Subject: [PATCH] [Fix] Ensure that hyperscan cache written is written properly

---
 src/hs_helper.c          | 22 ++++++++++++++++++++--
 src/libserver/re_cache.c | 11 ++++++++++-
 2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/src/hs_helper.c b/src/hs_helper.c
index 127cf2785..d2bcf891b 100644
--- a/src/hs_helper.c
+++ b/src/hs_helper.c
@@ -127,11 +127,11 @@ rspamd_hs_helper_cleanup_dir (struct hs_helper_ctx *ctx, gboolean forced)
 	}
 
 	globbuf.gl_offs = 0;
-	len = strlen (ctx->hs_dir) + 1 + sizeof ("*.hs");
+	len = strlen (ctx->hs_dir) + 1 + sizeof ("*.hs.new") + 2;
 	pattern = g_malloc (len);
 	rspamd_snprintf (pattern, len, "%s%c%s", ctx->hs_dir, G_DIR_SEPARATOR, "*.hs");
 
-	if ((rc = glob (pattern, GLOB_DOOFFS, NULL, &globbuf)) == 0) {
+	if ((rc = glob (pattern, 0, NULL, &globbuf)) == 0) {
 		for (i = 0; i < globbuf.gl_pathc; i++) {
 			if (forced ||
 					!rspamd_re_cache_is_valid_hyperscan_file (ctx->cfg->re_cache,
@@ -149,6 +149,24 @@ rspamd_hs_helper_cleanup_dir (struct hs_helper_ctx *ctx, gboolean forced)
 		ret = FALSE;
 	}
 
+	globfree (&globbuf);
+
+	memset (&globbuf, 0, sizeof (globbuf));
+	rspamd_snprintf (pattern, len, "%s%c%s", ctx->hs_dir, G_DIR_SEPARATOR, "*.hs.new");
+	if ((rc = glob (pattern, 0, NULL, &globbuf)) == 0) {
+		for (i = 0; i < globbuf.gl_pathc; i++) {
+			if (unlink (globbuf.gl_pathv[i]) == -1) {
+				msg_err ("cannot unlink %s: %s", globbuf.gl_pathv[i],
+						strerror (errno));
+				ret = FALSE;
+			}
+		}
+	}
+	else if (rc != GLOB_NOMATCH) {
+		msg_err ("glob %s failed: %s", pattern, strerror (errno));
+		ret = FALSE;
+	}
+
 	globfree (&globbuf);
 	g_free (pattern);
 
diff --git a/src/libserver/re_cache.c b/src/libserver/re_cache.c
index dc993513c..9fa2688a2 100644
--- a/src/libserver/re_cache.c
+++ b/src/libserver/re_cache.c
@@ -1318,7 +1318,7 @@ rspamd_re_cache_compile_hyperscan (struct rspamd_re_cache *cache,
 	GHashTableIter it, cit;
 	gpointer k, v;
 	struct rspamd_re_class *re_class;
-	gchar path[PATH_MAX];
+	gchar path[PATH_MAX], npath[PATH_MAX];
 	hs_database_t *test_db;
 	gint fd, i, n, *hs_ids = NULL, pcre_flags, re_flags;
 	guint64 crc;
@@ -1371,6 +1371,8 @@ rspamd_re_cache_compile_hyperscan (struct rspamd_re_cache *cache,
 			continue;
 		}
 
+		rspamd_snprintf (path, sizeof (path), "%s%c%s.hs.new", cache_dir,
+						G_DIR_SEPARATOR, re_class->hash);
 		fd = open (path, O_CREAT|O_TRUNC|O_EXCL|O_WRONLY, 00600);
 
 		if (fd == -1) {
@@ -1471,6 +1473,7 @@ rspamd_re_cache_compile_hyperscan (struct rspamd_re_cache *cache,
 				g_free (hs_ids);
 				g_free (hs_pats);
 				close (fd);
+				unlink (path);
 				hs_free_compile_error (hs_errors);
 
 				return -1;
@@ -1487,6 +1490,7 @@ rspamd_re_cache_compile_hyperscan (struct rspamd_re_cache *cache,
 						re_class->hash);
 
 				close (fd);
+				unlink (path);
 				g_free (hs_ids);
 				g_free (hs_flags);
 				hs_free_database (test_db);
@@ -1514,6 +1518,7 @@ rspamd_re_cache_compile_hyperscan (struct rspamd_re_cache *cache,
 			else {
 				iov[0].iov_base = (void *) rspamd_hs_magic;
 			}
+
 			iov[0].iov_len = RSPAMD_HS_MAGIC_LEN;
 			iov[1].iov_base = &cache->plt;
 			iov[1].iov_len = sizeof (cache->plt);
@@ -1535,6 +1540,7 @@ rspamd_re_cache_compile_hyperscan (struct rspamd_re_cache *cache,
 						"cannot serialize tree of regexp to %s: %s",
 						path, strerror (errno));
 				close (fd);
+				unlink (path);
 				g_free (hs_ids);
 				g_free (hs_flags);
 				g_free (hs_serialized);
@@ -1566,7 +1572,10 @@ rspamd_re_cache_compile_hyperscan (struct rspamd_re_cache *cache,
 			g_free (hs_flags);
 		}
 
+		fsync (fd);
 		close (fd);
+
+		/* Now rename temporary file to the new .hs file */
 	}
 
 	return total;
-- 
2.39.5