bugfix: potential problem (loop, abort) when file write error occured

When a write error occured in stream.c, variable iWritten had the error
code but this was handled as if it were the actual number of bytes
written. That was used in pointer arithmetic later on, and thus could
lead to all sorts of problems. However, this could only happen if the
error was EINTR or the file in question was a tty. All other cases were
handled properly. Now, iWritten is reset to zero in such cases, resulting
in proper retries.

3 files changed, 11 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 321963dd..5f495768 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 ---------------------------------------------------------------------------
 Version 4.6.2  [v4-stable] (rgerhards), 2010-03-??
+- bugfix: potential problem (loop, abort) when file write error occured
+  When a write error occured in stream.c, variable iWritten had the error
+  code but this was handled as if it were the actual number of bytes
+  written. That was used in pointer arithmetic later on, and thus could
+  lead to all sorts of problems. However, this could only happen if the
+  error was EINTR or the file in question was a tty. All other cases were
+  handled properly. Now, iWritten is reset to zero in such cases, resulting
+  in proper retries.
 - bugfix: $omfileFlushOnTXEnd was turned on when set to off and vice
   versa due to an invalid check
 - added new property replacer option "date-rfc3164-buggyday" primarily
diff --git a/runtime/stream.c b/runtime/stream.c
index 36f44003..82718099 100644
--- a/runtime/stream.c
+++ b/runtime/stream.c
@@ -790,6 +790,7 @@ doWriteCall(strm_t *pThis, uchar *pBuf, size_t *pLenBuf)
 		if(iWritten < 0) {
 			char errStr[1024];
 			int err = errno;
+			iWritten = 0; /* we have written NO bytes! */
 			rs_strerror_r(err, errStr, sizeof(errStr));
 			DBGPRINTF("log file (%d) write error %d: %s\n", pThis->fd, err, errStr);
 			if(err == EINTR) {
diff --git a/tools/omfile.c b/tools/omfile.c
index 8fbf8fea..daefa680 100644
--- a/tools/omfile.c
+++ b/tools/omfile.c
@@ -79,7 +79,7 @@ DEFobjCurrIf(strm)
 struct s_dynaFileCacheEntry {
 	uchar *pName;		/* name currently open, if dynamic name */
 	strm_t	*pStrm;		/* our output stream */
-	time_t	lastUsed;	/* for LRU - last access */ // TODO: perforamcne change to counter (see other comment!) 
+	time_t	lastUsed;	/* for LRU - last access */
 };
 typedef struct s_dynaFileCacheEntry dynaFileCacheEntry;
 
@@ -532,7 +532,7 @@ prepareDynFile(instanceData *pData, uchar *newFileName, unsigned iMsgOpts)
 		ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY);
 	}
 	pCache[iFirstFree]->pStrm = pData->pStrm;
-	pCache[iFirstFree]->lastUsed = time(NULL); // monotonically increasing value! TODO: performance
+	pCache[iFirstFree]->lastUsed = time(NULL);
 	pData->iCurrElt = iFirstFree;
 	DBGPRINTF("Added new entry %d for file cache, file '%s'.\n", iFirstFree, newFileName);