Florian Westphal <fw@xxxxxxxxx> wrote: > Cong Wang <xiyou.wangcong@xxxxxxxxx> wrote: > > While testing my TC filter patches (so not related to conntrack), the > > following memory leaks are shown up: > > > > unreferenced object 0xffff9b19ba551228 (size 128): > > comm "chronyd", pid 338, jiffies 4294910829 (age 53.188s) > > hex dump (first 32 bytes): > > 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk > > 00 00 00 00 18 00 00 30 00 00 00 00 00 00 00 00 .......0........ > > backtrace: > > [<ffffffff9f1e1175>] create_object+0x169/0x2aa > > [<ffffffff9fb77fb2>] kmemleak_alloc+0x25/0x41 > > [<ffffffff9f1c47ed>] slab_post_alloc_hook+0x44/0x65 > > [<ffffffff9f1ca2db>] __kmalloc_track_caller+0x113/0x146 > > [<ffffffff9f193c3b>] __krealloc+0x4a/0x69 > > [<ffffffff9f948dbd>] nf_ct_ext_add+0xe1/0x145 > > [<ffffffff9f942395>] init_conntrack+0x1f7/0x36e > > [<ffffffff9f942762>] nf_conntrack_in+0x1d3/0x326 > > [<ffffffff9fa1ea69>] ipv4_conntrack_local+0x4d/0x50 > > [<ffffffff9f93ad70>] nf_hook_slow+0x3c/0x9b > > [<ffffffff9f9c7999>] nf_hook.constprop.40+0xbe/0xd8 > > [<ffffffff9f9c7ba2>] __ip_local_out+0xb3/0xbf > > [<ffffffff9f9c7bca>] ip_local_out+0x1c/0x36 > > [<ffffffff9f9c9216>] ip_send_skb+0x19/0x3d > > [<ffffffff9f9ee3de>] udp_send_skb+0x17e/0x1df > > [<ffffffff9f9eea37>] udp_sendmsg+0x5a2/0x77c > > unreferenced object 0xffff9b19a69b3340 (size 336): > > comm "chronyd", pid 338, jiffies 4294910868 (age 53.032s) > > hex dump (first 32 bytes): > > 01 00 00 00 5a 5a 5a 5a 00 00 00 00 ad 4e ad de ....ZZZZ.....N.. > > ff ff ff ff 5a 5a 5a 5a ff ff ff ff ff ff ff ff ....ZZZZ........ > > backtrace: > > [<ffffffff9f1e1175>] create_object+0x169/0x2aa > > [<ffffffff9fb77fb2>] kmemleak_alloc+0x25/0x41 > > [<ffffffff9f1c47ed>] slab_post_alloc_hook+0x44/0x65 > > [<ffffffff9f1c7a7d>] kmem_cache_alloc+0xd7/0x1f1 > > [<ffffffff9f941b78>] __nf_conntrack_alloc+0xa2/0x146 > > [<ffffffff9f942250>] init_conntrack+0xb2/0x36e > > [<ffffffff9f942762>] nf_conntrack_in+0x1d3/0x326 > > [<ffffffff9fa1ea69>] ipv4_conntrack_local+0x4d/0x50 > > [<ffffffff9f93ad70>] nf_hook_slow+0x3c/0x9b > > [<ffffffff9f9c7999>] nf_hook.constprop.40+0xbe/0xd8 > > [<ffffffff9f9c7ba2>] __ip_local_out+0xb3/0xbf > > [<ffffffff9f9c7bca>] ip_local_out+0x1c/0x36 > > [<ffffffff9f9c9216>] ip_send_skb+0x19/0x3d > > [<ffffffff9f9ee3de>] udp_send_skb+0x17e/0x1df > > [<ffffffff9f9eea37>] udp_sendmsg+0x5a2/0x77c > > [<ffffffff9f9f8cb8>] inet_sendmsg+0x37/0x5e > > > > I don't touch chronyd in my VM, so I have no idea why it sends out UDP > > packets, my guess is it is some periodical packet. > > > > I don't think I use conntrack either, since /proc/net/ip_conntrack > > does not exist. > > You probably do, can you try "cat /proc/net/nf_conntrack" instead? > > (otherwise there should be no ipv4_conntrack_local() invocation > since we would not register this hook at all). > > I tried to reproduce this but so far I had no success. > If you can identify something that could give a hint when this > is happening (only once after boot, periodically, only with udp, etc) > please let us know. FWIW i managed to obtain a similar backtrace, but in that case it was a false positive (peeking at the address content showed it was my ssh connection to the vm and timeout and tcp conntrackk struct fields were changing; i.e. the nf_conn reported was still in the conntrack hash. Why this address was reported i do not know, afaik kmemleak does scan for addresses anywhere in the object (we use container_of() to get back nf_conn from the hlist_node), so it should have found the address linked via the main conntrack hash table. Right now I don't have enough info to dig any further, sorry :-/ -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
