From: teor <teor2345@gmail.com>
Date: Sun, 28 May 2017 12:12:09 +0000 (+1000)
Subject: Always check for usage underflow when removing a file in storage.c
X-Git-Tag: tor-0.3.1.3-alpha~23^2~4
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9e36b0beb9dc6fe02d43b4c217841c8164f41774;p=thirdparty%2Ftor.git

Always check for usage underflow when removing a file in storage.c

Part of #22424.
---

diff --git a/src/common/storagedir.c b/src/common/storagedir.c
index 6457f3d009..9140ed29bd 100644
--- a/src/common/storagedir.c
+++ b/src/common/storagedir.c
@@ -425,7 +425,9 @@ storage_dir_remove_file(storage_dir_t *d,
     }
   }
   if (unlink(ipath) == 0) {
-    d->usage -= size;
+    if (! BUG(d->usage < size)) {
+      d->usage -= size;
+    }
   } else {
     log_warn(LD_FS, "Unable to unlink %s", escaped(path));
     tor_free(path);