From: Jens Axboe axboe@kernel.dk
commit 9b8284921513fc1ea57d87777283a59b05862f03 upstream.
If we don't get and assign the namespace for the async work, then certain paths just don't work properly (like /dev/stdin, /proc/mounts, etc). Anything that references the current namespace of the given task should be assigned for async work on behalf of that task.
Cc: stable@vger.kernel.org # v5.5+ Reported-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/io-wq.c | 4 ++++ fs/io-wq.h | 1 + fs/io_uring.c | 3 +++ 3 files changed, 8 insertions(+)
--- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -60,6 +60,7 @@ struct io_worker { const struct cred *cur_creds; const struct cred *saved_creds; struct files_struct *restore_files; + struct nsproxy *restore_nsproxy; struct fs_struct *restore_fs; };
@@ -153,6 +154,7 @@ static bool __io_worker_unuse(struct io_
task_lock(current); current->files = worker->restore_files; + current->nsproxy = worker->restore_nsproxy; task_unlock(current); }
@@ -318,6 +320,7 @@ static void io_worker_start(struct io_wq
worker->flags |= (IO_WORKER_F_UP | IO_WORKER_F_RUNNING); worker->restore_files = current->files; + worker->restore_nsproxy = current->nsproxy; worker->restore_fs = current->fs; io_wqe_inc_running(wqe, worker); } @@ -454,6 +457,7 @@ static void io_impersonate_work(struct i if (work->files && current->files != work->files) { task_lock(current); current->files = work->files; + current->nsproxy = work->nsproxy; task_unlock(current); } if (work->fs && current->fs != work->fs) --- a/fs/io-wq.h +++ b/fs/io-wq.h @@ -88,6 +88,7 @@ struct io_wq_work { struct files_struct *files; struct mm_struct *mm; const struct cred *creds; + struct nsproxy *nsproxy; struct fs_struct *fs; unsigned flags; }; --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1456,6 +1456,7 @@ static void io_req_drop_files(struct io_ spin_unlock_irqrestore(&ctx->inflight_lock, flags); req->flags &= ~REQ_F_INFLIGHT; put_files_struct(req->work.files); + put_nsproxy(req->work.nsproxy); req->work.files = NULL; }
@@ -5685,6 +5686,8 @@ static int io_grab_files(struct io_kiocb return 0;
req->work.files = get_files_struct(current); + get_nsproxy(current->nsproxy); + req->work.nsproxy = current->nsproxy; req->flags |= REQ_F_INFLIGHT;
spin_lock_irq(&ctx->inflight_lock);