From: Jeffrey Hutzelman <jhutz@cmu.edu>
Date: Wed, 19 Jun 2013 03:12:46 +0000 (-0400)
Subject: viced/callback.c: Don't ignore dump read errors
X-Git-Tag: openafs-stable-1_8_0pre1~1072
X-Git-Url: https://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=c854cb31ff2b1ab79de18b5ab926bf2ea2b05663

viced/callback.c: Don't ignore dump read errors

When reading a callback state dump, check the return values from
read(2) instead of ignoring them.  This adds a new static function,
ReadBytes(), which handles reading a requested number of bytes from a
file and bailing if there is an error.

Change-Id: Ib06d96888b4e6de0a377c8c6503147f9e44960e5
Reviewed-on: http://gerrit.openafs.org/9989
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
---

diff --git a/src/viced/callback.c b/src/viced/callback.c
index edc2c63..cfaaa63 100644
--- a/src/viced/callback.c
+++ b/src/viced/callback.c
@@ -2702,6 +2702,22 @@ DumpCallBackState(void) {
 
 #ifdef INTERPRET_DUMP
 
+static void
+ReadBytes(int fd, void *buf, size_t req)
+{
+    ssize_t count;
+
+    count = read(fd, buf, req);
+    if (count < 0) {
+	perror("read");
+	exit(-1);
+    } else if (count != req) {
+	fprintf(stderr, "read: premature EOF (expected %lu, got %lu)\n",
+		(unsigned long)req, (unsigned long)count);
+	exit(-1);
+    }
+}
+
 /* This is only compiled in for the callback analyzer program */
 /* Returns the time of the dump */
 time_t
@@ -2721,7 +2737,7 @@ ReadDump(char *file, int timebits)
 	fprintf(stderr, "Couldn't read dump file %s\n", file);
 	exit(1);
     }
-    read(fd, &magic, sizeof(magic));
+    ReadBytes(fd, &magic, sizeof(magic));
     if (magic == MAGICV2) {
 	timebits = 32;
     } else {
@@ -2735,26 +2751,26 @@ ReadDump(char *file, int timebits)
 	}
     }
     if (timebits == 64) {
-	read(fd, &now64, sizeof(afs_int64));
+	ReadBytes(fd, &now64, sizeof(afs_int64));
 	now = (afs_int32) now64;
     } else
-	read(fd, &now, sizeof(afs_int32));
+	ReadBytes(fd, &now, sizeof(afs_int32));
 
-    read(fd, &cbstuff, sizeof(cbstuff));
-    read(fd, TimeOuts, sizeof(TimeOuts));
-    read(fd, timeout, sizeof(timeout));
-    read(fd, &tfirst, sizeof(tfirst));
-    read(fd, &freelisthead, sizeof(freelisthead));
+    ReadBytes(fd, &cbstuff, sizeof(cbstuff));
+    ReadBytes(fd, TimeOuts, sizeof(TimeOuts));
+    ReadBytes(fd, timeout, sizeof(timeout));
+    ReadBytes(fd, &tfirst, sizeof(tfirst));
+    ReadBytes(fd, &freelisthead, sizeof(freelisthead));
     CB = ((struct CallBack
 	   *)(calloc(cbstuff.nblks, sizeof(struct CallBack)))) - 1;
     FE = ((struct FileEntry
 	   *)(calloc(cbstuff.nblks, sizeof(struct FileEntry)))) - 1;
     CBfree = (struct CallBack *)itocb(freelisthead);
-    read(fd, &freelisthead, sizeof(freelisthead));
+    ReadBytes(fd, &freelisthead, sizeof(freelisthead));
     FEfree = (struct FileEntry *)itofe(freelisthead);
-    read(fd, HashTable, sizeof(HashTable));
-    read(fd, &CB[1], sizeof(CB[1]) * cbstuff.nblks);	/* CB stuff */
-    read(fd, &FE[1], sizeof(FE[1]) * cbstuff.nblks);	/* FE stuff */
+    ReadBytes(fd, HashTable, sizeof(HashTable));
+    ReadBytes(fd, &CB[1], sizeof(CB[1]) * cbstuff.nblks);	/* CB stuff */
+    ReadBytes(fd, &FE[1], sizeof(FE[1]) * cbstuff.nblks);	/* FE stuff */
     if (close(fd)) {
 	perror("Error reading dumpfile");
 	exit(1);