diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2024-08-01 15:27:39 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2024-08-02 11:30:32 +0200 |
| commit | bb18c5de1c288050ef8bd4af4ca16896ad4cd3fc (patch) | |
| tree | 9ca4aafead6f962321612826b3c34f9e0039ad46 /kernel/events/uprobes.c | |
| parent | 3c83a9ad0295eb63bdeb81d821b8c3b9417fbcac (diff) | |
| download | lwn-bb18c5de1c288050ef8bd4af4ca16896ad4cd3fc.tar.gz lwn-bb18c5de1c288050ef8bd4af4ca16896ad4cd3fc.zip | |
uprobes: change uprobe_register() to use uprobe_unregister() instead of __uprobe_unregister()
If register_for_each_vma() fails uprobe_register() can safely drop
uprobe->register_rwsem and use uprobe_unregister(). There is no worry
about the races with another register/unregister, consumer_add() was
already called so this case doesn't differ from _unregister() right
after the successful _register().
Yes this means the extra up_write() + down_write(), but this is the
slow and unlikely case anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240801132739.GA8809@redhat.com
Diffstat (limited to 'kernel/events/uprobes.c')
| -rw-r--r-- | kernel/events/uprobes.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index b33f1397dae0..eacf287ecd89 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1174,16 +1174,18 @@ struct uprobe *uprobe_register(struct inode *inode, if (likely(uprobe_is_active(uprobe))) { consumer_add(uprobe, uc); ret = register_for_each_vma(uprobe, uc); - if (ret) - __uprobe_unregister(uprobe, uc); } up_write(&uprobe->register_rwsem); put_uprobe(uprobe); - if (unlikely(ret == -EAGAIN)) - goto retry; + if (ret) { + if (unlikely(ret == -EAGAIN)) + goto retry; + uprobe_unregister(uprobe, uc); + return ERR_PTR(ret); + } - return ret ? ERR_PTR(ret) : uprobe; + return uprobe; } EXPORT_SYMBOL_GPL(uprobe_register); |