@@ -39,9 +39,18 @@ do { \
s = c; \
} while (0)
-#define ENDLINE \
- if (c > line) \
- line[c - line - 1] = '\n'
+static char *
+__endline(char *line, size_t len, char *c)
+{
+ if (c > line) {
+ if (c >= line + len)
+ c = line + len - 1;
+ *(c - 1) = '\n';
+ *c = '\0';
+ }
+ return c;
+}
+
#define PRINT(var, size, format, args...) \
do { \
fwd = snprintf(var, size, format, ##args); \
@@ -802,7 +811,7 @@ snprint_multipath_header (char * line, int len, char * format)
PAD(data->width);
} while (*f++);
- ENDLINE;
+ __endline(line, len, c);
return (c - line);
}
@@ -838,7 +847,7 @@ snprint_multipath (char * line, int len, char * format,
buff[0] = '\0';
} while (*f++);
- ENDLINE;
+ __endline(line, len, c);
return (c - line);
}
@@ -869,7 +878,7 @@ snprint_path_header (char * line, int len, char * format)
PAD(data->width);
} while (*f++);
- ENDLINE;
+ __endline(line, len, c);
return (c - line);
}
@@ -904,7 +913,7 @@ snprint_path (char * line, int len, char * format,
PAD(data->width);
} while (*f++);
- ENDLINE;
+ __endline(line, len, c);
return (c - line);
}
@@ -938,7 +947,7 @@ snprint_pathgroup (char * line, int len, char * format,
PAD(data->width);
} while (*f++);
- ENDLINE;
+ __endline(line, len, c);
return (c - line);
}
Under certain conditions, the output of "multipath -ll" or "multipathd show topology", or the multipathd logs, may contain garbage characters. Fix that by making sure that the strings are always properly zero-terminated. While touching this code, substitute a function for the complex ENDLINE macro. Note 1: The way this is coded, the previously written character is overwritten by the newline. That behavior is unchanged by this patch. I didn't want to fuzz with the carefully crafted print.c code more than necessary at this point. Note 2: The condition (c <= line + len - 1) is equivalent to (TAIL >= 0). It should always hold the way ENDLINE is called after PRINT and PAD in print.c, and is only added as an additional safeguard, e.g. against future code changes. Signed-off-by: Martin Wilck <mwilck@suse.com> --- libmultipath/print.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-)