[PATCH 4.18 060/123] fuse: fix double request_end()
From: Greg Kroah-Hartman
Date: Mon Sep 03 2018 - 13:43:04 EST
4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Miklos Szeredi <mszeredi@xxxxxxxxxx>
commit 87114373ea507895a62afb10d2910bd9adac35a8 upstream.
Refcounting of request is broken when fuse_abort_conn() is called and
request is on the fpq->io list:
- ref is taken too late
- then it is not dropped
Fixes: 0d8e84b0432b ("fuse: simplify request abort")
Cc: <stable@xxxxxxxxxxxxxxx> # v4.2
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/fuse/dev.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -371,7 +371,7 @@ static void request_end(struct fuse_conn
struct fuse_iqueue *fiq = &fc->iq;
if (test_and_set_bit(FR_FINISHED, &req->flags))
- return;
+ goto out_put_req;
spin_lock(&fiq->waitq.lock);
list_del_init(&req->intr_entry);
@@ -400,6 +400,7 @@ static void request_end(struct fuse_conn
wake_up(&req->waitq);
if (req->end)
req->end(fc, req);
+out_put_req:
fuse_put_request(fc, req);
}
@@ -2108,6 +2109,7 @@ void fuse_abort_conn(struct fuse_conn *f
set_bit(FR_ABORTED, &req->flags);
if (!test_bit(FR_LOCKED, &req->flags)) {
set_bit(FR_PRIVATE, &req->flags);
+ __fuse_get_request(req);
list_move(&req->list, &to_end1);
}
spin_unlock(&req->waitq.lock);
@@ -2134,7 +2136,6 @@ void fuse_abort_conn(struct fuse_conn *f
while (!list_empty(&to_end1)) {
req = list_first_entry(&to_end1, struct fuse_req, list);
- __fuse_get_request(req);
list_del_init(&req->list);
request_end(fc, req);
}