On 6/24/22 16:00, Dumitru Ceara wrote: > On 6/24/22 14:54, Ilya Maximets wrote: >> ofpbuf_reserve() can be called with a zero size for a buffer with >> an unallocated data. It's a valid case, but we should not allow >> evaluation of 'NULL + 0'. >> >> SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior lib/ofpbuf.c:469:30 >> in >> lib/ofpbuf.c:469:30: runtime error: applying zero offset to null pointer >> 0 0xb2f890 in ofpbuf_reserve lib/ofpbuf.c:469:30 >> 1 0xb2f9bc in ofpbuf_new_with_headroom lib/ofpbuf.c:179:5 >> 2 0xb2f9bc in ofpbuf_clone_data_with_headroom lib/ofpbuf.c:228:24 >> 3 0xb2f9bc in ofpbuf_clone_with_headroom lib/ofpbuf.c:199:18 >> 4 0xb2f8ea in ofpbuf_clone lib/ofpbuf.c:189:12 >> 5 0x6b3c57 in ukey_set_actions ofproto/ofproto-dpif-upcall.c:1712:5 >> 6 0x6c4315 in ukey_create__ ofproto/ofproto-dpif-upcall.c:1738:5 >> 7 0x6beed6 in ukey_create_from_upcall >> ofproto/ofproto-dpif-upcall.c:1793:12 >> 8 0x6beed6 in upcall_xlate ofproto/ofproto-dpif-upcall.c:1284:24 >> 9 0x6beed6 in process_upcall ofproto/ofproto-dpif-upcall.c:1456:9 >> 10 0x6bafb6 in recv_upcalls ofproto/ofproto-dpif-upcall.c:875:17 >> 11 0x6b70fa in udpif_upcall_handler ofproto/ofproto-dpif-upcall.c:792:13 >> 12 0xb4d5fa in ovsthread_wrapper lib/ovs-thread.c:422:12 >> 13 0x7fe6922081ce in start_thread (/lib64/libpthread.so.0+0x81ce) >> 14 0x7fe690e39dd2 in clone (/lib64/libc.so.6+0x39dd2) >> >> Signed-off-by: Ilya Maximets <[email protected]> >> --- >> lib/ofpbuf.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/lib/ofpbuf.c b/lib/ofpbuf.c >> index 79ced46d7..679f3ba3e 100644 >> --- a/lib/ofpbuf.c >> +++ b/lib/ofpbuf.c >> @@ -464,6 +464,10 @@ ofpbuf_put_hex(struct ofpbuf *b, const char *s, size_t >> *n) >> void >> ofpbuf_reserve(struct ofpbuf *b, size_t size) >> { >> + if (!size) { >> + return; >> + } >> + >> ovs_assert(!b->size); > > Just to be extra sure, I think I'd move the ovs_assert(!b->size) before > your new check. > > Anyhow, it's ok without or it can be done at apply time: > > Acked-by: Dumitru Ceara <[email protected]>
Thanks, Aaron and Dumitru! I moved the assert and applied the patch. Also backported down to 2.13. Best regards, Ilya Maximets. _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
