diff options
| author | Sabrina Dubroca <sd@queasysnail.net> | 2017-12-31 18:18:56 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-02-25 13:07:46 +0300 |
| commit | e8370258ca0bc9e630043157db862be2c5c341a6 (patch) | |
| tree | 390b90f3d540b04cf9df193de4d224ec761f3b90 /net | |
| parent | 85c31887a20da06fe2803b4ec1031b9af89c1899 (diff) | |
| download | linux-e8370258ca0bc9e630043157db862be2c5c341a6.tar.xz | |
xfrm: fix rcu usage in xfrm_get_type_offload
commit 2f10a61cee8fdb9f8da90f5db687e1862b22cf06 upstream.
request_module can sleep, thus we cannot hold rcu_read_lock() while
calling it. The function also jumps back and takes rcu_read_lock()
again (in xfrm_state_get_afinfo()), resulting in an imbalance.
This codepath is triggered whenever a new offloaded state is created.
Fixes: ffdb5211da1c ("xfrm: Auto-load xfrm offload modules")
Reported-by: syzbot+ca425f44816d749e8eb49755567a75ee48cf4a30@syzkaller.appspotmail.com
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/xfrm/xfrm_state.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c index 1f5cee2269af..58be0e7f4c7d 100644 --- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -313,13 +313,14 @@ retry: if ((type && !try_module_get(type->owner))) type = NULL; + rcu_read_unlock(); + if (!type && try_load) { request_module("xfrm-offload-%d-%d", family, proto); try_load = 0; goto retry; } - rcu_read_unlock(); return type; } |