xfstests: fix modulo-by-zero error in fsx

The recent fsx fixes has a logic error in the offset trimming code. If a read is done when the file size is zero, then the logic error causes a offset % 0 opertaion to occur. This causes fsx to get a SIGFPE and die. This was not discovered during my testing because I was using a random seed that didn't trip this condition. Changing the seed to that which test 091 uses (the default of 1) causes such an operation to occur.... Signed-off-by: Dave Chinner <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]>
zfsonlinux · Jul 19, 2011 · c47d7a5 · c47d7a5
1 parent 407191f
commit c47d7a5
Showing 1 changed file with 8 additions and 8 deletions.
diff --git a/ltp/fsx.c b/ltp/fsx.c
@@ -987,14 +987,14 @@ docloseopen(void)
 	}
 }
 
-#define TRIM_OFF_LEN(off, len, size, zero_offset)	\
-do {					\
-	if (!zero_offset || file_size)	\
-		offset %= size;		\
-	else				\
-		offset = 0;		\
-	if (offset + len > size)	\
-		len = size - offset;	\
+#define TRIM_OFF_LEN(off, len, size, allow_zero_file_size)	\
+do {						\
+	if (allow_zero_file_size || file_size)	\
+		offset %= size;			\
+	else					\
+		offset = 0;			\
+	if (offset + len > size)		\
+		len = size - offset;		\
 } while (0)
 
 void