diff options
| author | Francois-Xavier Le Bail <devel.fx.lebail@orange.fr> | 2021-11-21 15:33:24 +0100 |
|---|---|---|
| committer | Francois-Xavier Le Bail <devel.fx.lebail@orange.fr> | 2021-11-21 15:49:13 +0100 |
| commit | d52b757efa7b0678e34c0ffe32d1c0da29bbb604 (patch) | |
| tree | 5992a60baa0cbed3999f3ab2214e471adcb154db /print-ether.c | |
| parent | 84b51cad218840ece9115c72705f846060005c6f (diff) | |
| download | tcpdump-d52b757efa7b0678e34c0ffe32d1c0da29bbb604.tar.gz | |
Ethernet: Rework the length checks
Add a sanity check: packet length need to be >= capture length
(Like a sanity check in print.c, pretty_print_packet() function)
Remove a now useless test:
Because packet length (length) >= capture length (caplen), when
caplen >= ETHER_HDRLEN + switch_tag_len, length cannot
be < ETHER_HDRLEN + switch_tag_len.
Diffstat (limited to 'print-ether.c')
| -rw-r--r-- | print-ether.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/print-ether.c b/print-ether.c index 3aeda8f7..954668c4 100644 --- a/print-ether.c +++ b/print-ether.c @@ -150,14 +150,15 @@ ether_common_print(netdissect_options *ndo, const u_char *p, u_int length, int llc_hdrlen; struct lladdr_info src, dst; + if (length < caplen) { + ND_PRINT("[length %u < caplen %u]", length, caplen); + nd_print_invalid(ndo); + return length; + } if (caplen < ETHER_HDRLEN + switch_tag_len) { nd_print_trunc(ndo); return caplen; } - if (length < ETHER_HDRLEN + switch_tag_len) { - nd_print_trunc(ndo); - return length; - } if (print_encap_header != NULL) (*print_encap_header)(ndo, encap_header_arg); |