net: caif: clear client service pointer on teardown

`caif_connect()` can tear down an existing client after remote shutdown by
calling `caif_disconnect_client()` followed by `caif_free_client()`.
`caif_free_client()` releases the service layer referenced by
`adap_layer->dn`, but leaves that pointer stale.

When the socket is later destroyed, `caif_sock_destructor()` calls
`caif_free_client()` again and dereferences the freed service pointer.

Clear the client/service links before releasing the service object so
repeated teardown becomes harmless.

Fixes: 43e3692101 ("caif: Move refcount from service layer to sock and dev.")
Cc: stable@kernel.org
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Co-developed-by: Yuan Tan <yuantan098@gmail.com>
Signed-off-by: Yuan Tan <yuantan098@gmail.com>
Suggested-by: Xin Liu <bird@lzu.edu.cn>
Tested-by: Ren Wei <enjou1224z@gmail.com>
Signed-off-by: Zhengchuan Liang <zcliangcn@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Link: https://patch.msgid.link/9f3d37847c0037568aae698ca23cd47c6691acb0.1775897577.git.zcliangcn@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Zhengchuan Liang
2026-04-11 23:10:26 +08:00
committed by Paolo Abeni
parent fe72340daa
commit f7cf8ece8c

View File

@@ -191,10 +191,20 @@ bool cfsrvl_phyid_match(struct cflayer *layer, int phyid)
void caif_free_client(struct cflayer *adap_layer)
{
struct cflayer *serv_layer;
struct cfsrvl *servl;
if (adap_layer == NULL || adap_layer->dn == NULL)
if (!adap_layer)
return;
servl = container_obj(adap_layer->dn);
serv_layer = adap_layer->dn;
if (!serv_layer)
return;
layer_set_dn(adap_layer, NULL);
layer_set_up(serv_layer, NULL);
servl = container_obj(serv_layer);
servl->release(&servl->layer);
}
EXPORT_SYMBOL(caif_free_client);