From: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx> Date: Sat, 25 Apr 2020 20:54:37 +0800 > bpf_exec_tx_verdict() invokes sk_psock_get(), which returns a reference > of the specified sk_psock object to "psock" with increased refcnt. > > When bpf_exec_tx_verdict() returns, local variable "psock" becomes > invalid, so the refcount should be decreased to keep refcount balanced. > > The reference counting issue happens in one exception handling path of > bpf_exec_tx_verdict(). When "policy" equals to NULL but "psock" is not > NULL, the function forgets to decrease the refcnt increased by > sk_psock_get(), causing a refcnt leak. > > Fix this issue by calling sk_psock_put() on this error path before > bpf_exec_tx_verdict() returns. > > Signed-off-by: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx> > Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx> Applied and queued up for -stable.
