mir/ovs
2
0
Fork 0
mirror of https://github.com/openvswitch/ovs synced 2025-08-31 22:35:15 +00:00
Code Issues Releases Wiki Activity

ipf: release unhandled packets from the batch

Browse Source 
Since 640d4db788 ("ipf: Fix a use-after-free error, ...") the ipf
framework unconditionally allocates a new dp_packet to track
individual fragments.  This prevents a use-after-free.  However, an
additional issue was present - even when the packet buffer is cloned,
if the ip fragment handling code keeps it, the original buffer is
leaked during the refill loop.  Even in the original processing code,
the hardcoded dnsteal branches would always leak a packet buffer from
the refill loop.

This can be confirmed with valgrind:

==717566== 16,672 (4,480 direct, 12,192 indirect) bytes in 8 blocks are definitely lost in loss record 390 of 390
==717566==    at 0x484086F: malloc (vg_replace_malloc.c:380)
==717566==    by 0x537BFD: xmalloc__ (util.c:137)
==717566==    by 0x537BFD: xmalloc (util.c:172)
==717566==    by 0x46DDD4: dp_packet_new (dp-packet.c:153)
==717566==    by 0x46DDD4: dp_packet_new_with_headroom (dp-packet.c:163)
==717566==    by 0x550AA6: netdev_linux_batch_rxq_recv_sock.constprop.0 (netdev-linux.c:1262)
==717566==    by 0x5512AF: netdev_linux_rxq_recv (netdev-linux.c:1511)
==717566==    by 0x4AB7E0: netdev_rxq_recv (netdev.c:727)
==717566==    by 0x47F00D: dp_netdev_process_rxq_port (dpif-netdev.c:4699)
==717566==    by 0x47FD13: dpif_netdev_run (dpif-netdev.c:5957)
==717566==    by 0x4331D2: type_run (ofproto-dpif.c:370)
==717566==    by 0x41DFD8: ofproto_type_run (ofproto.c:1768)
==717566==    by 0x40A7FB: bridge_run__ (bridge.c:3245)
==717566==    by 0x411269: bridge_run (bridge.c:3310)
==717566==    by 0x406E6C: main (ovs-vswitchd.c:127)

The fix is to delete the original packet when it isn't able to be
reinserted into the packet batch.  Subsequent valgrind runs show that
the packets are not leaked from the batch any longer.

Fixes: 640d4db788 ("ipf: Fix a use-after-free error, and remove the 'do_not_steal' flag.")
Fixes: 4ea96698f6 ("Userspace datapath: Add fragmentation handling.")
Reported-by: Wan Junjie <wanjunjie@bytedance.com>
Reported-at: https://github.com/openvswitch/ovs-issues/issues/226
Signed-off-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>
Tested-by: Wan Junjie <wanjunjie@bytedance.com>
Signed-off-by: Alin-Gabriel Serdean <aserdean@ovn.org>
This commit is contained in:
Aaron Conole
2021-10-05 14:18:44 -04:00
committed by Alin-Gabriel Serdean
parent 13d05b8e5b
commit 803ed12e31
1 changed files with 2 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
lib/ipf.c
View File

@@ -943,6 +943,8 @@ ipf_extract_frags_from_batch(struct ipf *ipf, struct dp_packet_batch *pb,
ovs_mutex_lock(&ipf->ipf_lock);
if (!ipf_handle_frag(ipf, pkt, dl_type, zone, now, hash_basis)) {
dp_packet_batch_refill(pb, pkt, pb_idx);
} else {
dp_packet_delete(pkt);
}
ovs_mutex_unlock(&ipf->ipf_lock);
} else {