Ben Hutchings 2dc3b21fbc net: Allow driver to limit number of GSO segments per skb ... [ Upstream commit 30b678d844 ] A peer (or local user) may cause TCP to use a nominal MSS of as little as 88 (actual MSS of 76 with timestamps). Given that we have a sufficiently prodigious local sender and the peer ACKs quickly enough, it is nevertheless possible to grow the window for such a connection to the point that we will try to send just under 64K at once. This results in a single skb that expands to 861 segments. In some drivers with TSO support, such an skb will require hundreds of DMA descriptors; a substantial fraction of a TX ring or even more than a full ring. The TX queue selected for the skb may stall and trigger the TX watchdog repeatedly (since the problem skb will be retried after the TX reset). This particularly affects sfc, for which the issue is designated as CVE-2012-3412. Therefore: 1. Add the field net_device::gso_max_segs holding the device-specific limit. 2. In netif_skb_features(), if the number of segments is too high then mask out GSO features to force fall back to software GSO. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2012-10-02 10:29:34 -07:00
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acpi	Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux	2012-05-05 10:06:06 -07:00
asm-generic	thp: avoid atomic64_read in pmd_read_atomic for 32bit PAE	2012-07-16 09:04:42 -07:00
crypto	crypto: user - Fix lookup of algorithms with IV generator	2012-03-29 19:52:47 +08:00
drm	drm/radeon: add some new SI pci ids	2012-08-26 15:00:41 -07:00
keys
linux	net: Allow driver to limit number of GSO segments per skb	2012-10-02 10:29:34 -07:00
math-emu
media	Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media	2012-05-14 11:23:37 -07:00
misc
mtd
net	bonding: Fix corrupted queue_mapping	2012-07-16 09:03:47 -07:00
pcmcia
rdma	Merge branches 'cma', 'cxgb3', 'cxgb4', 'ehca', 'iser', 'mad', 'nes', 'qib', 'srp' and 'srpt' into for-next	2012-03-19 09:50:33 -07:00
rxrpc
scsi	SCSI: libsas: fix taskfile corruption in sas_ata_qc_fill_rtf	2012-07-16 09:04:37 -07:00
sound	ALSA: hda - hide HDMI/ELD printks unless snd.debug=2	2012-04-10 14:53:55 +02:00
target	target: Add generation of LOGICAL BLOCK ADDRESS OUT OF RANGE	2012-08-09 08:31:26 -07:00
trace	random: add tracepoints for easier debugging and verification	2012-08-15 08:10:28 -07:00
video	Merge branch 'platforms' of git://git.linaro.org/people/rmk/linux-arm	2012-03-27 18:17:02 -07:00
xen	xen: do not map the same GSI twice in PVHVM guests.	2012-06-01 15:18:25 +08:00
Kbuild