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2011-08-07Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller10-25/+40
2011-08-07ipv4: use dst with ref during bcast/mcast loopbackJulian Anastasov1-0/+1
Make sure skb dst has reference when moving to another context. Currently, I don't see protocols that can hit it when sending broadcasts/multicasts to loopback using noref dsts, so it is just a precaution. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07ipv4: route non-local sources for raw socketJulian Anastasov1-1/+2
The raw sockets can provide source address for routing but their privileges are not considered. We can provide non-local source address, make sure the FLOWI_FLAG_ANYSRC flag is set if socket has privileges for this, i.e. based on hdrincl (IP_HDRINCL) and transparent flags. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07netfilter: TCP and raw fix for ip_route_me_harderJulian Anastasov1-10/+8
TCP in some cases uses different global (raw) socket to send RST and ACK. The transparent flag is not set there. Currently, it is a problem for rerouting after the previous change. Fix it by simplifying the checks in ip_route_me_harder and use FLOWI_FLAG_ANYSRC even for sockets. It looks safe because the initial routing allowed this source address to be used and now we just have to make sure the packet is rerouted. As a side effect this also allows rerouting for normal raw sockets that use spoofed source addresses which was not possible even before we eliminated the ip_route_input call. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07ipv4: Fix ip_getsockopt for IP_PKTOPTIONSDaniel Baluta1-4/+5
IP_PKTOPTIONS is broken for 32-bit applications running in COMPAT mode on 64-bit kernels. This happens because msghdr's msg_flags field is always set to zero. When running in COMPAT mode this should be set to MSG_CMSG_COMPAT instead. Signed-off-by: Tiberiu Szocs-Mihai <tszocs@ixiacom.com> Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-07ipv4: fix the reusing of routing cache entriesJulian Anastasov1-1/+2
compare_keys and ip_route_input_common rely on rt_oif for distinguishing of input and output routes with same keys values. But sometimes the input route has also same hash chain (keyed by iif != 0) with the output routes (keyed by orig_oif=0). Problem visible if running with small number of rhash_entries. Fix them to use rt_route_iif instead. By this way input route can not be returned to users that request output route. The patch fixes the ip_rt_bug errors that were reported in ip_local_out context, mostly for 255.255.255.255 destinations. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-06net: Compute protocol sequence numbers and fragment IDs using MD5.David S. Miller5-0/+5
Computers have become a lot faster since we compromised on the partial MD4 hash which we use currently for performance reasons. MD5 is a much safer choice, and is inline with both RFC1948 and other ISS generators (OpenBSD, Solaris, etc.) Furthermore, only having 24-bits of the sequence number be truly unpredictable is a very serious limitation. So the periodic regeneration and 8-bit counter have been removed. We compute and use a full 32-bit sequence number. For ipv6, DCCP was found to use a 32-bit truncated initial sequence number (it needs 43-bits) and that is fixed here as well. Reported-by: Dan Kaminsky <dan@doxpara.com> Tested-by: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-03net: fix NULL dereferences in check_peer_redir()Eric Dumazet2-8/+16
Gergely Kalman reported crashes in check_peer_redir(). It appears commit f39925dbde778 (ipv4: Cache learned redirect information in inetpeer.) added a race, leading to possible NULL ptr dereference. Since we can now change dst neighbour, we should make sure a reader can safely use a neighbour. Add RCU protection to dst neighbour, and make sure check_peer_redir() can be called safely by different cpus in parallel. As neighbours are already freed after one RCU grace period, this patch should not add typical RCU penalty (cache cold effects) Many thanks to Gergely for providing a pretty report pointing to the bug. Reported-by: Gergely Kalman <synapse@hippy.csoma.elte.hu> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-02rcu: convert uses of rcu_assign_pointer(x, NULL) to RCU_INIT_POINTERStephen Hemminger16-88/+88
When assigning a NULL value to an RCU protected pointer, no barrier is needed. The rcu_assign_pointer, used to handle that but will soon change to not handle the special case. Convert all rcu_assign_pointer of NULL value. //smpl @@ expression P; @@ - rcu_assign_pointer(P, NULL) + RCU_INIT_POINTER(P, NULL) // </smpl> Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-01net: adjust array indexJulia Lawall1-1/+1
Convert array index from the loop bound to the loop index. A simplified version of the semantic patch that fixes this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression e1,e2,ar; @@ for(e1 = 0; e1 < e2; e1++) { <... ar[ - e2 + e1 ] ...> } // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds1-8/+8
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (32 commits) tg3: Remove 5719 jumbo frames and TSO blocks tg3: Break larger frags into 4k chunks for 5719 tg3: Add tx BD budgeting code tg3: Consolidate code that calls tg3_tx_set_bd() tg3: Add partial fragment unmapping code tg3: Generalize tg3_skb_error_unmap() tg3: Remove short DMA check for 1st fragment tg3: Simplify tx bd assignments tg3: Reintroduce tg3_tx_ring_info ASIX: Use only 11 bits of header for data size ASIX: Simplify condition in rx_fixup() Fix cdc-phonet build bonding: reduce noise during init bonding: fix string comparison errors net: Audit drivers to identify those needing IFF_TX_SKB_SHARING cleared net: add IFF_SKB_TX_SHARED flag to priv_flags net: sock_sendmsg_nosec() is static forcedeth: fix vlans gianfar: fix bug caused by 87c288c6e9aa31720b72e2bc2d665e24e1653c3e gro: Only reset frag0 when skb can be pulled ...
2011-07-26atomic: use <linux/atomic.h>Arun Sharma2-2/+2
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25IPv4: Send gratuitous ARP for secondary IP addresses alsoZoltan Kiss1-8/+8
If a device event generates gratuitous ARP messages, only primary address is used for sending. This patch iterates through the whole list. Tested with 2 IP addresses configuration on bonding interface. Signed-off-by: Zoltan Kiss <schaman@sch.bme.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-23gre: fix improper error handlingxeb@mail.ru1-15/+6
Fix improper protocol err_handler, current implementation is fully unapplicable and may cause kernel crash due to double kfree_skb. Signed-off-by: Dmitry Kozlov <xeb@mail.ru> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-23ipv4: use RT_TOS after some rt_tos conversionsJulian Anastasov2-2/+2
rt_tos was changed to iph->tos but it must be filtered by RT_TOS Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-22icmp: Fix regression in nexthop resolution during replies.David S. Miller1-6/+8
icmp_route_lookup() uses the wrong flow parameters if the reverse session route lookup isn't used. So do not commit to the re-decoded flow until we actually make a final decision to use a real route saved in 'rt2'. Reported-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21ipv4: Constrain UFO fragment sizes to multiples of 8 bytesBill Sommerfeld1-3/+3
Because the ip fragment offset field counts 8-byte chunks, ip fragments other than the last must contain a multiple of 8 bytes of payload. ip_ufo_append_data wasn't respecting this constraint and, depending on the MTU and ip option sizes, could create malformed non-final fragments. Google-Bug-Id: 5009328 Signed-off-by: Bill Sommerfeld <wsommerfeld@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21ipv6: make fragment identifications less predictableEric Dumazet1-2/+5
IPv6 fragment identification generation is way beyond what we use for IPv4 : It uses a single generator. Its not scalable and allows DOS attacks. Now inetpeer is IPv6 aware, we can use it to provide a more secure and scalable frag ident generator (per destination, instead of system wide) This patch : 1) defines a new secure_ipv6_id() helper 2) extends inet_getid() to provide 32bit results 3) extends ipv6_select_ident() with a new dest parameter Reported-by: Fernando Gont <fernando@gont.com.ar> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21lro: do vlan cleanupJiri Pirko1-28/+11
- remove useless vlan parameters and pointers Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21lro: kill lro_vlan_hwaccel_receive_fragsJiri Pirko1-20/+0
Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-21lro: kill lro_vlan_hwaccel_receive_skbJiri Pirko1-15/+0
no longer used Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-18ipv4: save cpu cycles from check_leaf()Eric Dumazet1-6/+6
Compiler is not smart enough to avoid double BSWAP instructions in ntohl(inet_make_mask(plen)). Lets cache this value in struct leaf_info, (fill a hole on 64bit arches) With route cache disabled, this saves ~2% of cpu in udpflood bench on x86_64 machine. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-18net: Add ->neigh_lookup() operation to dst_opsDavid S. Miller1-7/+19
In the future dst entries will be neigh-less. In that environment we need to have an easy transition point for current users of dst->neighbour outside of the packet output fast path. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-17net: Abstract dst->neighbour accesses behind helpers.David S. Miller3-14/+15
dst_{get,set}_neighbour() Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-17neigh: Pass neighbour entry to output ops.David S. Miller1-3/+3
This will get us closer to being able to do "neigh stuff" completely independent of the underlying dst_entry for protocols (ipv4/ipv6) that wish to do so. We will also be able to make dst entries neigh-less. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16neigh: Kill ndisc_ops->queue_xmitDavid S. Miller1-5/+1
It is always dev_queue_xmit(). Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16neigh: Kill hh_cache->hh_outputDavid S. Miller1-3/+3
It's just taking on one of two possible values, either neigh_ops->output or dev_queue_xmit(). And this is purely depending upon whether nud_state has NUD_CONNECTED set or not. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16neigh: Kill neigh_ops->hh_outputDavid S. Miller1-4/+0
It's always dev_queue_xmit(). Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16net: Create and use new helper, neigh_output().David S. Miller1-7/+3
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-16ipv4: Use calculated 'neigh' instead of re-evaluating dst->neighbourDavid S. Miller1-1/+1
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-14Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller2-16/+4
Conflicts: net/bluetooth/l2cap_core.c
2011-07-14net: Embed hh_cache inside of struct neighbour.David S. Miller2-8/+13
Now that there is a one-to-one correspondance between neighbour and hh_cache entries, we no longer need: 1) dynamic allocation 2) attachment to dst->hh 3) refcounting Initialization of the hh_cache entry is indicated by hh_len being non-zero, and such initialization is always done with the neighbour's lock held as a writer. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-13ipv4: Inline neigh binding.David Miller2-27/+27
Get rid of all of the useless and costly indirection by doing the neigh hash table lookup directly inside of the neighbour binding. Rename from arp_bind_neighbour to rt_bind_neighbour. Use new helpers {__,}ipv4_neigh_lookup() In rt_bind_neighbour() get rid of useless tests which are never true in the context this function is called, namely dev is never NULL and the dst->neighbour is always NULL. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-11inetpeer: kill inet_putpeer raceEric Dumazet1-5/+9
We currently can free inetpeer entries too early : [ 782.636674] WARNING: kmemcheck: Caught 32-bit read from uninitialized memory (f130f44c) [ 782.636677] 1f7b13c100000000000000000000000002000000000000000000000000000000 [ 782.636686] i i i i u u u u i i i i u u u u i i i i u u u u u u u u u u u u [ 782.636694] ^ [ 782.636696] [ 782.636698] Pid: 4638, comm: ssh Not tainted 3.0.0-rc5+ #270 Hewlett-Packard HP Compaq 6005 Pro SFF PC/3047h [ 782.636702] EIP: 0060:[<c13fefbb>] EFLAGS: 00010286 CPU: 0 [ 782.636707] EIP is at inet_getpeer+0x25b/0x5a0 [ 782.636709] EAX: 00000002 EBX: 00010080 ECX: f130f3c0 EDX: f0209d30 [ 782.636711] ESI: 0000bc87 EDI: 0000ea60 EBP: f0209ddc ESP: c173134c [ 782.636712] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 [ 782.636714] CR0: 8005003b CR2: f0beca80 CR3: 30246000 CR4: 000006d0 [ 782.636716] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 782.636717] DR6: ffff4ff0 DR7: 00000400 [ 782.636718] [<c13fbf76>] rt_set_nexthop.clone.45+0x56/0x220 [ 782.636722] [<c13fc449>] __ip_route_output_key+0x309/0x860 [ 782.636724] [<c141dc54>] tcp_v4_connect+0x124/0x450 [ 782.636728] [<c142ce43>] inet_stream_connect+0xa3/0x270 [ 782.636731] [<c13a8da1>] sys_connect+0xa1/0xb0 [ 782.636733] [<c13a99dd>] sys_socketcall+0x25d/0x2a0 [ 782.636736] [<c149deb8>] sysenter_do_call+0x12/0x28 [ 782.636738] [<ffffffff>] 0xffffffff Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-11ipv4: Use universal hash for ARP.David S. Miller1-2/+1
We need to make sure the multiplier is odd. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-07net: refine {udp|tcp|sctp}_mem limitsEric Dumazet2-16/+4
Current tcp/udp/sctp global memory limits are not taking into account hugepages allocations, and allow 50% of ram to be used by buffers of a single protocol [ not counting space used by sockets / inodes ...] Lets use nr_free_buffer_pages() and allow a default of 1/8 of kernel ram per protocol, and a minimum of 128 pages. Heavy duty machines sysadmins probably need to tweak limits anyway. References: https://bugzilla.stlinux.com/show_bug.cgi?id=38032 Reported-by: starlight <starlight@binnacle.cx> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-05Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6David S. Miller6-61/+46
2011-07-05ipv4: Add ip_defrag() agent IP_DEFRAG_AF_PACKET.David S. Miller1-2/+3
Elide the ICMP on frag queue timeouts unconditionally for this user. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-04net: bind() fix error return on wrong address familyMarcus Meissner1-1/+3
Hi, Reinhard Max also pointed out that the error should EAFNOSUPPORT according to POSIX. The Linux manpages have it as EINVAL, some other OSes (Minix, HPUX, perhaps BSD) use EAFNOSUPPORT. Windows uses WSAEFAULT according to MSDN. Other protocols error values in their af bind() methods in current mainline git as far as a brief look shows: EAFNOSUPPORT: atm, appletalk, l2tp, llc, phonet, rxrpc EINVAL: ax25, bluetooth, decnet, econet, ieee802154, iucv, netlink, netrom, packet, rds, rose, unix, x25, No check?: can/raw, ipv6/raw, irda, l2tp/l2tp_ip Ciao, Marcus Signed-off-by: Marcus Meissner <meissner@suse.de> Cc: Reinhard Max <max@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01xfrm4: Don't call icmp_send on local errorSteffen Klassert1-1/+6
Calling icmp_send() on a local message size error leads to an incorrect update of the path mtu. So use ip_local_error() instead to notify the socket about the error. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01ipv4: Don't use ufo handling on later transformed packetsSteffen Klassert1-1/+1
We might call ip_ufo_append_data() for packets that will be IPsec transformed later. This function should be used just for real udp packets. So we check for rt->dst.header_len which is only nonzero on IPsec handling and call ip_ufo_append_data() just if rt->dst.header_len is zero. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01ipv4: Reduce switch/case indentJoe Perches2-32/+32
Make the case labels the same indent as the switch. git diff -w shows no difference. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01netfilter: Reduce switch/case indentJoe Perches2-119/+117
Make the case labels the same indent as the switch. git diff -w shows miscellaneous 80 column wrapping, comment reflowing and a comment for a useless gcc warning for an otherwise unused default: case. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-01ipconfig: Reduce switch/case indentJoe Perches1-35/+38
Make the case labels the same indent as the switch. git diff -w shows miscellaneous 80 column wrapping. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-29netfilter: Fix ip_route_me_harder triggering ip_rt_bugJulian Anastasov2-48/+26
Avoid creating input routes with ip_route_me_harder. It does not work for locally generated packets. Instead, restrict sockets to provide valid saddr for output route (or unicast saddr for transparent proxy). For other traffic allow saddr to be unicast or local but if callers forget to check saddr type use 0 for the output route. The resulting handling should be: - REJECT TCP: - in INPUT we can provide addr_type = RTN_LOCAL but better allow rejecting traffic delivered with local route (no IP address => use RTN_UNSPEC to allow also RTN_UNICAST). - FORWARD: RTN_UNSPEC => allow RTN_LOCAL/RTN_UNICAST saddr, add fix to ignore RTN_BROADCAST and RTN_MULTICAST - OUTPUT: RTN_UNSPEC - NAT, mangle, ip_queue, nf_ip_reroute: RTN_UNSPEC in LOCAL_OUT - IPVS: - use RTN_LOCAL in LOCAL_OUT and FORWARD after SNAT to restrict saddr to be local Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-27ipv4: Fix IPsec slowpath fragmentation problemSteffen Klassert1-5/+5
ip_append_data() builds packets based on the mtu from dst_mtu(rt->dst.path). On IPsec the effective mtu is lower because we need to add the protocol headers and trailers later when we do the IPsec transformations. So after the IPsec transformations the packet might be too big, which leads to a slowpath fragmentation then. This patch fixes this by building the packets based on the lower IPsec mtu from dst_mtu(&rt->dst) and adapts the exthdr handling to this. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-27ipv4: Fix packet size calculation in __ip_append_dataSteffen Klassert1-5/+2
Git commit 59104f06 (ip: take care of last fragment in ip_append_data) added a check to see if we exceed the mtu when we add trailer_len. However, the mtu is already subtracted by the trailer length when the xfrm transfomation bundles are set up. So IPsec packets with mtu size get fragmented, or if the DF bit is set the packets will not be send even though they match the mtu perfectly fine. This patch actually reverts commit 59104f06. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21udp/recvmsg: Clear MSG_TRUNC flag when starting over for a new packetXufeng Zhang1-0/+3
Consider this scenario: When the size of the first received udp packet is bigger than the receive buffer, MSG_TRUNC bit is set in msg->msg_flags. However, if checksum error happens and this is a blocking socket, it will goto try_again loop to receive the next packet. But if the size of the next udp packet is smaller than receive buffer, MSG_TRUNC flag should not be set, but because MSG_TRUNC bit is not cleared in msg->msg_flags before receive the next packet, MSG_TRUNC is still set, which is wrong. Fix this problem by clearing MSG_TRUNC flag when starting over for a new packet. Signed-off-by: Xufeng Zhang <xufeng.zhang@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21ip: introduce ip_is_fragment helper inline functionPaul Gortmaker6-7/+7
There are enough instances of this: iph->frag_off & htons(IP_MF | IP_OFFSET) that a helper function is probably warranted. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21udp: add tracepoints for queueing skb to rcvbufSatoru Moriya1-0/+2
This patch adds a tracepoint to __udp_queue_rcv_skb to get the return value of ip_queue_rcv_skb. It indicates why kernel drops a packet at this point. ip_queue_rcv_skb returns following values in the packet drop case: rcvbuf is full : -ENOMEM sk_filter returns error : -EINVAL, -EACCESS, -ENOMEM, etc. __sk_mem_schedule returns error: -ENOBUF Signed-off-by: Satoru Moriya <satoru.moriya@hds.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>