net: fix a resource leak in copy_net_ns() error handling path

Browse source

Currently, preinit_net() does two things:

  (1) call ns_common_init() which might fail
  (2) initialize resources which does not fail

However, preinit_net() is returning early when (1) fails, and copy_net_ns()
is jumping to the dec_ucounts: label. As a result, resources allocated by
net_alloc() are leaking. We need to call key_remove_domain() and
net_passive_dec() in order to release resources allocated by net_alloc().

We cannot simply jump to the put_userns: label when preinit_net() failed,
for (2) is not yet done. But we can reorder (1) and (2), for there is no
dependency between (1) and (2). Therefore, this patch decouples (1) from
preinit_net() and changes preinit_net() back to a void function, and calls
ns_common_init() after preinit_net() succeeded. Then, we can jump to
immediately after ns_common_free() of the put_userns: label.

Reported-by: sashiko (no mail address)
Closes: https://sashiko.dev/#/patchset/af7dabf3-d0d7-46dc-a878-e1715b3c9ac6%40I-love.SAKURA.ne.jp
Fixes: 08027f6b79 ("net: use ns_common_init()")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: https://patch.msgid.link/c182cf90-1ed7-435b-88f7-9f00e88a0487@I-love.SAKURA.ne.jp
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

...

This commit is contained in:

Tetsuo Handa 2026-08-22 17:18:31 +09:00 • committed by Paolo Abeni

parent 97148bcb75

commit 3220b62fbb

1 changed files with 9 additions and 12 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

21

net/core/net_namespace.c

View file