diff options
| -rw-r--r-- | sysdeps/unix/sysv/linux/if_index.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/sysdeps/unix/sysv/linux/if_index.c b/sysdeps/unix/sysv/linux/if_index.c index 76349bd96d..92fb11b180 100644 --- a/sysdeps/unix/sysv/linux/if_index.c +++ b/sysdeps/unix/sysv/linux/if_index.c @@ -16,6 +16,7 @@ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ +#include <alloca.h> #include <errno.h> #include <string.h> #include <stdio.h> @@ -118,17 +119,21 @@ if_nameindex (void) rq_len = RQ_IFS * sizeof (struct ifreq); /* Read all the interfaces out of the kernel. */ - do + ifc.ifc_buf = alloca (rq_len); + ifc.ifc_len = rq_len; + while (1) { - ifc.ifc_buf = alloca (ifc.ifc_len = rq_len); - if (__ioctl (fd, SIOCGIFCONF, &ifc) < 0) + if (__ioctl (fd, SIOCGIFCONF, &ifc) < 0) { close_not_cancel_no_status (fd); return NULL; } - rq_len *= 2; + if (ifc.ifc_len < rq_len || ! old_siocgifconf) + break; + + ifc.ifc_buf = extend_alloca (ifc.ifc_buf, rq_len, 2 * rq_len); + ifc.ifc_len = rq_len; } - while (ifc.ifc_len == rq_len && old_siocgifconf); nifs = ifc.ifc_len / sizeof (struct ifreq); |