vfs: fix BUG_ON() in fs/namei.c:1461
When Al moved the nameidata_dentry_drop_rcu_maybe() call into the
do_follow_link function in commit 844a391799c2 ("nothing in
do_follow_link() is going to see RCU"), he mistakenly left the
BUG_ON(inode != path->dentry->d_inode);
behind. Which would otherwise be ok, but that BUG_ON() really needs to
be _after_ dropping RCU, since the dentry isn't necessarily stable
otherwise.
So complete the code movement in that commit, and move the BUG_ON() into
do_follow_link() too. This means that we need to pass in 'inode' as an
argument (just for this one use), but that's a small thing. And
eventually we may be confident enough in our path lookup that we can
just remove the BUG_ON() and the unnecessary inode argument.
Reported-and-tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 file changed