Jeremy Kerr 6c52b12159 mctp: perform route lookups under a RCU read-side lock ... [ Upstream commit 5093bbfc10 ] Our current route lookups (mctp_route_lookup and mctp_route_lookup_null) traverse the net's route list without the RCU read lock held. This means the route lookup is subject to preemption, resulting in an potential grace period expiry, and so an eventual kfree() while we still have the route pointer. Add the proper read-side critical section locks around the route lookups, preventing premption and a possible parallel kfree. The remaining net->mctp.routes accesses are already under a rcu_read_lock, or protected by the RTNL for updates. Based on an analysis from Sili Luo <rootlab@huawei.com>, where introducing a delay in the route lookup could cause a UAF on simultaneous sendmsg() and route deletion. Reported-by: Sili Luo <rootlab@huawei.com> Fixes: 889b7da23a ("mctp: Add initial routing framework") Cc: stable@vger.kernel.org Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/29c4b0e67dc1bf3571df3982de87df90cae9b631.1696837310.git.jk@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-10-25 11:58:59 +02:00
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Kconfig	mctp: Add MCTP base	2021-07-29 15:06:49 +01:00
Makefile	mctp: Add neighbour implementation	2021-07-29 15:06:50 +01:00
af_mctp.c	net: mctp: purge receive queues on sk destruction	2023-02-06 07:59:02 +01:00
device.c	mctp: Allow per-netns default networks	2021-07-29 15:06:50 +01:00
neigh.c	mctp: Add neighbour netlink interface	2021-07-29 15:06:50 +01:00
route.c	mctp: perform route lookups under a RCU read-side lock	2023-10-25 11:58:59 +02:00