diff options
Diffstat (limited to 'udp.c')
| -rw-r--r-- | udp.c | 26 |
1 files changed, 18 insertions, 8 deletions
@@ -704,11 +704,20 @@ static void udp_sock_fill_data_v4(const struct ctx *c, int n, b->uh.len = htons(udp4_l2_mh_sock[n].msg_len + sizeof(b->uh)); if (c->mode == MODE_PASTA) { - PRAGMA_STRINGOP_OVERREAD_IGNORE - if (write(c->fd_tap, &b->eh, sizeof(b->eh) + ip_len) < 0) + /* If we pass &b->eh directly to write(), starting from + * gcc 12.1, at least on aarch64 and x86_64, we get a bogus + * stringop-overread warning, due to: + * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103483 + * + * but we can't disable it with a pragma, because it will be + * ignored if LTO is enabled: + * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80922 + */ + void *frame = (char *)b + offsetof(struct udp4_l2_buf_t, eh); + + if (write(c->fd_tap, frame, sizeof(b->eh) + ip_len) < 0) debug("tap write: %s", strerror(errno)); - PRAGMA_STRINGOP_OVERREAD_IGNORE_POP - pcap((char *)&b->eh, sizeof(b->eh) + ip_len); + pcap(frame, sizeof(b->eh) + ip_len); return; } @@ -805,11 +814,12 @@ static void udp_sock_fill_data_v6(const struct ctx *c, int n, b->ip6h.hop_limit = 255; if (c->mode == MODE_PASTA) { - PRAGMA_STRINGOP_OVERREAD_IGNORE - if (write(c->fd_tap, &b->eh, sizeof(b->eh) + ip_len) < 0) + /* See udp_sock_fill_data_v4() for the reason behind 'frame' */ + void *frame = (char *)b + offsetof(struct udp6_l2_buf_t, eh); + + if (write(c->fd_tap, frame, sizeof(b->eh) + ip_len) < 0) debug("tap write: %s", strerror(errno)); - PRAGMA_STRINGOP_OVERREAD_IGNORE_POP - pcap((char *)&b->eh, sizeof(b->eh) + ip_len); + pcap(frame, sizeof(b->eh) + ip_len); return; } |