Re: [PATCH net] ipv6: fix possible deadlock in rt6_age_examine_exception()

2018-03-23 Thread David Miller
From: Eric Dumazet Date: Fri, 23 Mar 2018 07:56:58 -0700 > syzbot reported a LOCKDEP splat [1] in rt6_age_examine_exception() > > rt6_age_examine_exception() is called while rt6_exception_lock is held. > This lock is the lower one in the lock hierarchy, thus we can not > call dst_neigh_lookup()

Re: [PATCH net] ipv6: fix possible deadlock in rt6_age_examine_exception()

2018-03-23 Thread Wei Wang
On Fri, Mar 23, 2018 at 7:57 AM Eric Dumazet wrote: > syzbot reported a LOCKDEP splat [1] in rt6_age_examine_exception() > rt6_age_examine_exception() is called while rt6_exception_lock is held. > This lock is the lower one in the lock hierarchy, thus we can not > call dst_neigh_lookup() functio

[PATCH net] ipv6: fix possible deadlock in rt6_age_examine_exception()

2018-03-23 Thread Eric Dumazet
syzbot reported a LOCKDEP splat [1] in rt6_age_examine_exception() rt6_age_examine_exception() is called while rt6_exception_lock is held. This lock is the lower one in the lock hierarchy, thus we can not call dst_neigh_lookup() function, as it can fallback to neigh_create() We should instead do