From bc17c3dbe5cba37dab0be6a9ad1d7aeecdb7f117 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 3 May 2023 18:11:35 +0300 Subject: [PATCH] xen/pvcalls-back: fix double frees with pvcalls_new_active_socket() commit 8fafac202d18230bb9926bda48e563fd2cce2a4f upstream. In the pvcalls_new_active_socket() function, most error paths call pvcalls_back_release_active(fedata->dev, fedata, map) which calls sock_release() on "sock". The bug is that the caller also frees sock. Fix this by making every error path in pvcalls_new_active_socket() release the sock, and don't free it in the caller. Fixes: bee0949af1e5 ("xen/pvcalls: implement connect command") Signed-off-by: Dan Carpenter Reviewed-by: Juergen Gross Link: https://lore.kernel.org/r/e5f98dc2-0305-491f-a860-71bbd1398a2f@kili.mountain Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman --- drivers/xen/pvcalls-back.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c index 9c267e27d9d95..6c2afd8bbf522 100644 --- a/drivers/xen/pvcalls-back.c +++ b/drivers/xen/pvcalls-back.c @@ -321,8 +321,10 @@ static struct sock_mapping *pvcalls_new_active_socket( void *page; map = kzalloc(sizeof(*map), GFP_KERNEL); - if (map == NULL) + if (map == NULL) { + sock_release(sock); return NULL; + } map->fedata = fedata; map->sock = sock; @@ -414,10 +416,8 @@ static int pvcalls_back_connect(struct xenbus_device *dev, req->u.connect.ref, req->u.connect.evtchn, sock); - if (!map) { + if (!map) ret = -EFAULT; - sock_release(sock); - } out: rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); @@ -558,7 +558,6 @@ static void __pvcalls_back_accept(struct work_struct *work) sock); if (!map) { ret = -EFAULT; - sock_release(sock); goto out_error; } -- 2.39.5