diff options
| -rw-r--r-- | slirp/tftp.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/slirp/tftp.c b/slirp/tftp.c index 3b8643b8d8..082f5d0409 100644 --- a/slirp/tftp.c +++ b/slirp/tftp.c @@ -284,11 +284,12 @@ static void tftp_handle_rrq(Slirp *slirp, struct tftp_t *tp, int pktlen) /* prepend tftp_prefix */ prefix_len = strlen(slirp->tftp_prefix); - spt->filename = qemu_malloc(prefix_len + TFTP_FILENAME_MAX + 1); + spt->filename = qemu_malloc(prefix_len + TFTP_FILENAME_MAX + 2); memcpy(spt->filename, slirp->tftp_prefix, prefix_len); + spt->filename[prefix_len] = '/'; /* get name */ - req_fname = spt->filename + prefix_len; + req_fname = spt->filename + prefix_len + 1; while (1) { if (k >= TFTP_FILENAME_MAX || k >= pktlen) { @@ -315,7 +316,8 @@ static void tftp_handle_rrq(Slirp *slirp, struct tftp_t *tp, int pktlen) k += 6; /* skipping octet */ /* do sanity checks on the filename */ - if (req_fname[0] != '/' || req_fname[strlen(req_fname) - 1] == '/' || + if (!strncmp(req_fname, "../", 3) || + req_fname[strlen(req_fname) - 1] == '/' || strstr(req_fname, "/../")) { tftp_send_error(spt, 2, "Access violation", tp); return; |