[ Upstream commit 87151b8689d890dfb495081f7be9b9e257f7a2df ] Marc Merlin reported many order-1 allocations failures in TX path on its wireless setup, that dont make any sense with MTU=1500 network, and non SG capable hardware. Turns out part of the problem comes from pskb_expand_head() not using ksize() to get exact head size given by kmalloc(). Doing the same thing than __alloc_skb() allows more tailroom in skb and can prevent future reallocations. As a bonus, struct skb_shared_info becomes cache line aligned. Reported-by: Marc MERLIN <marc@merlins.org> Tested-by: Marc MERLIN <marc@merlins.org> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 110c43304db6f06490961529536c362d9ac5732f ] As soon as an skb is queued into socket error queue, another thread can consume it, so we are not allowed to reference skb anymore, or risk use after free. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use IS_ENABLED(CONFIG_FOO) instead of defined(CONFIG_FOO) || defined (CONFIG_FOO_MODULE) Signed-off-by: Igor Maravić <igorm@etf.rs> Signed-off-by: David S. Miller <davem@davemloft.net>
We discovered that TCP stack could retransmit misaligned skbs if a malicious peer acknowledged sub MSS frame. This currently can happen only if output interface is non SG enabled : If SG is enabled, tcp builds headless skbs (all payload is included in fragments), so the tcp trimming process only removes parts of skb fragments, header stay aligned. Some arches cant handle misalignments, so force a head reallocation and shrink headroom to MAX_TCP_HEADER. Dont care about misaligments on x86 and PPC (or other arches setting NET_IP_ALIGN to 0) This patch introduces __pskb_copy() which can specify the headroom of new head, and pskb_copy() becomes a wrapper on top of __pskb_copy() Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts: net/ipv4/inet_diag.c
when skb_shift, we want to shift paged data from skb to tgt frag area. Original comments revert the shift order Signed-off-by: Feng King <kinwin2008@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts: include/net/bluetooth/bluetooth.h
v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
One of the thing we discussed during netdev 2011 conference was the idea
to change some network drivers to allocate/populate their skb at RX
completion time, right before feeding the skb to network stack.
In old days, we allocated skbs when populating the RX ring.
This means bringing into cpu cache sk_buff and skb_shared_info cache
lines (since we clear/initialize them), then 'queue' skb->data to NIC.
By the time NIC fills a frame in skb->data buffer and host can process
it, cpu probably threw away the cache lines from its caches, because lot
of things happened between the allocation and final use.
So the deal would be to allocate only the data buffer for the NIC to
populate its RX ring buffer. And use build_skb() at RX completion to
attach a data buffer (now filled with an ethernet frame) to a new skb,
initialize the skb_shared_info portion, and give the hot skb to network
stack.
build_skb() is the function to allocate an skb, caller providing the
data buffer that should be attached to it. Drivers are expected to call
skb_reserve() right after build_skb() to adjust skb->data to the
Ethernet frame (usually skipping NET_SKB_PAD and NET_IP_ALIGN, but some
drivers might add a hardware provided alignment)
Data provided to build_skb() MUST have been allocated by a prior
kmalloc() call, with enough room to add SKB_DATA_ALIGN(sizeof(struct
skb_shared_info)) bytes at the end of the data without corrupting
incoming frame.
data = kmalloc(NET_SKB_PAD + NET_IP_ALIGN + 1536 +
SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
GFP_ATOMIC);
...
skb = build_skb(data);
if (!skb) {
recycle_data(data);
} else {
skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
...
}
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Eilon Greenstein <eilong@broadcom.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
CC: Tom Herbert <therbert@google.com>
CC: Jamal Hadi Salim <hadi@mojatatu.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Thomas Graf <tgraf@infradead.org>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The 802.1X EAPOL handshake hostapd does requires knowing whether the frame was ack'ed by the peer. Currently, we fudge this pretty badly by not even transmitting the frame as a normal data frame but injecting it with radiotap and getting the status out of radiotap monitor as well. This is rather complex, confuses users (mon.wlan0 presence) and doesn't work with all hardware. To get rid of that hack, introduce a real wifi TX status option for data frame transmissions. This works similar to the existing TX timestamping in that it reflects the SKB back to the socket's error queue with a SCM_WIFI_STATUS cmsg that has an int indicating ACK status (0/1). Since it is possible that at some point we will want to have TX timestamping and wifi status in a single errqueue SKB (there's little point in not doing that), redefine SO_EE_ORIGIN_TIMESTAMPING to SO_EE_ORIGIN_TXSTATUS which can collect more than just the timestamp; keep the old constant as an alias of course. Currently the internal APIs don't make that possible, but it wouldn't be hard to split them up in a way that makes it possible. Thanks to Neil Horman for helping me figure out the functions that add the control messages. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>