From: Jonathan Dieter <jdieter@gmail.com>
Date: Tue, 4 Apr 2023 20:11:12 +0000 (+0100)
Subject: Handle read_data errors correctly
X-Git-Tag: archive/raspbian/1.3.1+ds1-1+rpi1^2~5^2~2
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=e9e393ae40d016541d28ba7059d33a4fffb2e6ed;p=zchunk.git

Handle read_data errors correctly

The read_data function returns the number of bytes written, not a boolean,
so fix the error checking so we exit if fewer than expected bytes were
read.  Thanks to Agostino Sarubbo of Gentoo for providing a bug report with
a reproducible test case.

Signed-off-by: Jonathan Dieter <jdieter@gmail.com>
---

diff --git a/src/lib/header.c b/src/lib/header.c
index 565071e..7253207 100644
--- a/src/lib/header.c
+++ b/src/lib/header.c
@@ -101,8 +101,10 @@ static bool read_header_from_file(zckCtx *zck) {
     zck_log(ZCK_LOG_DEBUG, "Reading the rest of the header: %llu bytes",
             (long long unsigned) zck->header_length);
     if(loaded < zck->header_length) {
-        if(!read_data(zck, header + loaded, zck->header_length - loaded))
+        if(read_data(zck, header + loaded, zck->header_length - loaded) < zck->header_length - loaded) {
+            set_fatal_error(zck, "Unable to read %llu bytes from the file", zck->header_length - loaded);
             return false;
+        }
         zck->header_size = zck->lead_size + zck->header_length;
     }