From d88b41ba577a55c7735388a70794f539753cbfd7 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 26 Jul 2021 07:59:23 -0400 Subject: [PATCH] SUNRPC: Fix potential memory corruption [ Upstream commit c2dc3e5fad13aca5d7bdf4bcb52b1a1d707c8555 ] We really should not call rpc_wake_up_queued_task_set_status() with xprt->snd_task as an argument unless we are certain that is actually an rpc_task. Fixes: 0445f92c5d53 ("SUNRPC: Fix disconnection races") Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin --- include/linux/sunrpc/xprt.h | 1 + net/sunrpc/xprt.c | 6 ++++-- 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index c8c39f22d3b16..59cd97da895b7 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -432,6 +432,7 @@ void xprt_release_write(struct rpc_xprt *, struct rpc_task *); #define XPRT_CONGESTED (9) #define XPRT_CWND_WAIT (10) #define XPRT_WRITE_SPACE (11) +#define XPRT_SND_IS_COOKIE (12) static inline void xprt_set_connected(struct rpc_xprt *xprt) { diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index fb6db09725c76..bddd354a0076d 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -775,9 +775,9 @@ void xprt_force_disconnect(struct rpc_xprt *xprt) /* Try to schedule an autoclose RPC call */ if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) queue_work(xprtiod_workqueue, &xprt->task_cleanup); - else if (xprt->snd_task) + else if (xprt->snd_task && !test_bit(XPRT_SND_IS_COOKIE, &xprt->state)) rpc_wake_up_queued_task_set_status(&xprt->pending, - xprt->snd_task, -ENOTCONN); + xprt->snd_task, -ENOTCONN); spin_unlock(&xprt->transport_lock); } EXPORT_SYMBOL_GPL(xprt_force_disconnect); @@ -866,6 +866,7 @@ bool xprt_lock_connect(struct rpc_xprt *xprt, goto out; if (xprt->snd_task != task) goto out; + set_bit(XPRT_SND_IS_COOKIE, &xprt->state); xprt->snd_task = cookie; ret = true; out: @@ -881,6 +882,7 @@ void xprt_unlock_connect(struct rpc_xprt *xprt, void *cookie) if (!test_bit(XPRT_LOCKED, &xprt->state)) goto out; xprt->snd_task =NULL; + clear_bit(XPRT_SND_IS_COOKIE, &xprt->state); xprt->ops->release_xprt(xprt, NULL); xprt_schedule_autodisconnect(xprt); out: