Xie He dec629e972 net: lapb: Copy the skb before sending a packet ... [ Upstream commit 88c7a9fd9bdd3e453f04018920964c6f848a591a ] When sending a packet, we will prepend it with an LAPB header. This modifies the shared parts of a cloned skb, so we should copy the skb rather than just clone it, before we prepend the header. In "Documentation/networking/driver.rst" (the 2nd point), it states that drivers shouldn't modify the shared parts of a cloned skb when transmitting. The "dev_queue_xmit_nit" function in "net/core/dev.c", which is called when an skb is being sent, clones the skb and sents the clone to AF_PACKET sockets. Because the LAPB drivers first remove a 1-byte pseudo-header before handing over the skb to us, if we don't copy the skb before prepending the LAPB header, the first byte of the packets received on AF_PACKET sockets can be corrupted. Fixes: 1da177e4c3 ("Linux-2.6.12-rc2") Signed-off-by: Xie He <xie.he.0141@gmail.com> Acked-by: Martin Schiller <ms@dev.tdt.de> Link: https://lore.kernel.org/r/20210201055706.415842-1-xie.he.0141@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-02-10 09:29:14 +01:00
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Kconfig	treewide: replace '---help---' in Kconfig files with 'help'	2020-06-14 01:57:21 +09:00
lapb_iface.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2019-06-17 20:20:36 -07:00
lapb_in.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 41	2019-05-24 17:27:12 +02:00
lapb_out.c	net: lapb: Copy the skb before sending a packet	2021-02-10 09:29:14 +01:00
lapb_subr.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 41	2019-05-24 17:27:12 +02:00
lapb_timer.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 41	2019-05-24 17:27:12 +02:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00