On 2020/05/07 21:05, Jens Axboe <axboe@xxxxxxxxx> wrote: > On 5/7/20 1:01 PM, Al Viro wrote: > > On Thu, May 07, 2020 at 08:57:25PM +0200, Max Kellermann wrote: > >> If an operation's flag `needs_file` is set, the function > >> io_req_set_file() calls io_file_get() to obtain a `struct file*`. > >> > >> This fails for `O_PATH` file descriptors, because those have no > >> `struct file*` > > > > O_PATH descriptors most certainly *do* have that. What the hell > > are you talking about? > > Yeah, hence I was interested in the test case. Since this is > bypassing that part, was assuming we'd have some logic error > that attempted a file grab for a case where we shouldn't. Reproduce this by patching liburing/test/lfs-openat.c: - int dfd = open("/tmp", O_RDONLY | O_DIRECTORY); + int dfd = open("/tmp", O_PATH); $ ./test/lfs-openat io_uring openat failed: Bad file descriptor GH PR: https://github.com/axboe/liburing/pull/130 Max