commit f4b0df7bfe0f4016bb2d3ff90f36f00b76a02f57
parent 312fb51c9cc56cd9bc5dc1fb72c331b847a37eec
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date: Sun, 28 Feb 2016 17:35:48 +0100
sfeed_frames: fix TOCTTUO with access() and fopen()
... and use futimens() in favor of deprecated utime().
a minor difference in behaviour is now filetimes are only updated when the
file doesn't exist.
minor cleanup: remove namelen, its variable was unused (reported by cppcheck).
Diffstat:
1 file changed, 23 insertions(+), 15 deletions(-)
diff --git a/sfeed_frames.c b/sfeed_frames.c
@@ -4,6 +4,7 @@
#include <ctype.h>
#include <err.h>
#include <errno.h>
+#include <fcntl.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
@@ -18,7 +19,7 @@
static struct feed **feeds;
static char *line;
static size_t linesize;
-static struct utimbuf contenttime;
+static struct timespec times[2];
static time_t comparetime;
static unsigned long totalnew;
@@ -109,7 +110,7 @@ printfeed(FILE *fpitems, FILE *fpin, struct feed *f)
FILE *fpcontent = NULL;
unsigned int isnew;
time_t parsedtime;
- int r;
+ int fd, r;
if (f->name[0])
feedname = f->name;
@@ -117,7 +118,7 @@ printfeed(FILE *fpitems, FILE *fpin, struct feed *f)
feedname = "unnamed";
/* make directory for feedname */
- if (!(namelen = normalizepath(feedname, name, sizeof(name))))
+ if (!normalizepath(feedname, name, sizeof(name)))
return;
strlcpy(dirpath, name, sizeof(dirpath));
@@ -144,16 +145,22 @@ printfeed(FILE *fpitems, FILE *fpin, struct feed *f)
if (!parseline(line, fields))
break;
/* write content */
- if (!(namelen = normalizepath(fields[FieldTitle], name, sizeof(name))))
+ if (!normalizepath(fields[FieldTitle], name, sizeof(name)))
continue;
r = snprintf(filepath, sizeof(filepath), "%s/%s.html", dirpath, name);
if (r == -1 || (size_t)r >= sizeof(filepath))
errx(1, "snprintf: path truncation: '%s/%s.html'", dirpath, name);
+ parsedtime = 0;
+ strtotime(fields[FieldUnixTimestamp], &parsedtime);
+
/* content file doesn't exist yet and has write access */
- if (access(filepath, F_OK) != 0) {
- if (!(fpcontent = fopen(filepath, "w+b")))
- err(1, "fopen: %s", filepath);
+ if ((fd = open(filepath, O_CREAT | O_EXCL)) == -1) {
+ if (errno == EACCES)
+ err(1, "open: %s", filepath);
+ } else {
+ if (!(fpcontent = fdopen(fd, "w+b")))
+ err(1, "fdopen: %s", filepath);
fputs("<html><head>"
"<link rel=\"stylesheet\" type=\"text/css\" href=\"../../style.css\" />"
"<meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\" />"
@@ -175,15 +182,16 @@ printfeed(FILE *fpitems, FILE *fpin, struct feed *f)
fputs("</pre>", fpcontent);
}
fputs("</div></body></html>", fpcontent);
- fclose(fpcontent);
- }
- /* set modified and access time of file to time of item. */
- parsedtime = 0;
- if (strtotime(fields[FieldUnixTimestamp], &parsedtime) != -1) {
- contenttime.actime = parsedtime;
- contenttime.modtime = parsedtime;
- utime(filepath, &contenttime);
+ /* set modified and access time of file to time of item. */
+ if (parsedtime) {
+ times[0].tv_sec = parsedtime;
+ times[1].tv_sec = parsedtime;
+
+ if (futimens(fd, times) == -1)
+ err(1, "futimens");
+ }
+ fclose(fpcontent);
}
isnew = (parsedtime >= comparetime) ? 1 : 0;
