From: Pavel Begunkov asml.silence@gmail.com
mainline inclusion from mainline-5.8-rc2 commit 801dd57bd1d8c2c253f43635a3045bfa32a810b3 category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA ---------------------------
For an exiting process it tries to cancel all its inflight requests. Use req->task to match such instead of work.pid. We always have req->task set, and it will be valid because we're matching only current exiting task.
Also, remove work.pid and everything related, it's useless now.
Reported-by: Eric W. Biederman ebiederm@xmission.com Signed-off-by: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: yangerkun yangerkun@huawei.com Reviewed-by: zhangyi (F) yi.zhang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- fs/io-wq.h | 1 - fs/io_uring.c | 16 ++++++---------- 2 files changed, 6 insertions(+), 11 deletions(-)
diff --git a/fs/io-wq.h b/fs/io-wq.h index b72538fe5afd..071f1a997800 100644 --- a/fs/io-wq.h +++ b/fs/io-wq.h @@ -90,7 +90,6 @@ struct io_wq_work { const struct cred *creds; struct fs_struct *fs; unsigned flags; - pid_t task_pid; };
static inline struct io_wq_work *wq_next_work(struct io_wq_work *work) diff --git a/fs/io_uring.c b/fs/io_uring.c index cb032f2730a8..2639dcc4945e 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1062,8 +1062,6 @@ static inline void io_req_work_grab_env(struct io_kiocb *req, } spin_unlock(¤t->fs->lock); } - if (!req->work.task_pid) - req->work.task_pid = task_pid_vnr(current); }
static inline void io_req_work_drop_env(struct io_kiocb *req) @@ -7409,11 +7407,12 @@ static void io_uring_cancel_files(struct io_ring_ctx *ctx, } }
-static bool io_cancel_pid_cb(struct io_wq_work *work, void *data) +static bool io_cancel_task_cb(struct io_wq_work *work, void *data) { - pid_t pid = (pid_t) (unsigned long) data; + struct io_kiocb *req = container_of(work, struct io_kiocb, work); + struct task_struct *task = data;
- return work->task_pid == pid; + return req->task == task; }
static int io_uring_flush(struct file *file, void *data) @@ -7425,11 +7424,8 @@ static int io_uring_flush(struct file *file, void *data) /* * If the task is going away, cancel work it may have pending */ - if (fatal_signal_pending(current) || (current->flags & PF_EXITING)) { - void *data = (void *) (unsigned long)task_pid_vnr(current); - - io_wq_cancel_cb(ctx->io_wq, io_cancel_pid_cb, data, true); - } + if (fatal_signal_pending(current) || (current->flags & PF_EXITING)) + io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, current, true);
return 0; }