route: fix bogus read error when route table is empty

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2015-02-03 19:42:28 +01:00
parent 09020b1aa8
commit a75dcd4353

View File

@ -494,6 +494,7 @@ void FAST_FUNC bb_displayroutes(int noresolve, int netstatfmt)
{
char devname[64], flags[16], *sdest, *sgw;
unsigned long d, g, m;
int r;
int flgs, ref, use, metric, mtu, win, ir;
struct sockaddr_in s_addr;
struct in_addr mask;
@ -504,20 +505,24 @@ void FAST_FUNC bb_displayroutes(int noresolve, int netstatfmt)
"Destination Gateway Genmask Flags %s Iface\n",
netstatfmt ? " MSS Window irtt" : "Metric Ref Use");
if (fscanf(fp, "%*[^\n]\n") < 0) { /* Skip the first line. */
goto ERROR; /* Empty or missing line, or read error. */
/* Skip the first line. */
r = fscanf(fp, "%*[^\n]\n");
if (r < 0) {
/* Empty line, read error, or EOF. Yes, if routing table
* is completely empty, /proc/net/route has no header.
*/
goto ERROR;
}
while (1) {
int r;
r = fscanf(fp, "%63s%lx%lx%X%d%d%d%lx%d%d%d\n",
devname, &d, &g, &flgs, &ref, &use, &metric, &m,
&mtu, &win, &ir);
if (r != 11) {
ERROR:
if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
break;
}
ERROR:
bb_error_msg_and_die("fscanf");
bb_perror_msg_and_die(bb_msg_read_error);
}
if (!(flgs & RTF_UP)) { /* Skip interfaces that are down. */
@ -583,7 +588,7 @@ static void INET6_displayroutes(void)
break;
}
ERROR:
bb_error_msg_and_die("fscanf");
bb_perror_msg_and_die(bb_msg_read_error);
}
/* Do the addr6x shift-and-insert changes to ':'-delimit addresses.