tree cc452db3f2730c1aa6aa0815198c225aa162a884
parent 231ca22bdf24c587c5bc8dc6ed0e0ac16d773970
author Shreyansh Chouhan <chouhan.shreyansh630@gmail.com> 1629530064 +0530
committer Eva Huang <evahuang@google.com> 1635733854 +0800

ip_gre: add validation for csum_start

[ Upstream commit 1d011c4803c72f3907eccfc1ec63caefb852fcbf ]

Validate csum_start in gre_handle_offloads before we call _gre_xmit so
that we do not crash later when the csum_start value is used in the
lco_csum function call.

This patch deals with ipv4 code.

Bug: 150694665
Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.")
Reported-by: syzbot+ff8e1b9f2f36481e2efc@syzkaller.appspotmail.com
Signed-off-by: Shreyansh Chouhan <chouhan.shreyansh630@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: If54a12b14b667d46532326e885c39fec52dfe442