e7637a492b
io_provided_buffer_select() must drop the submit lock, if needed, even in the error handling case. Failure to do so will leave us with the ctx->uring_lock held, causing spew like: ==================================== WARNING: iou-wrk-366/368 still has locks held! 5.18.0-rc6-00294-gdf8dc7004331 #994 Not tainted ------------------------------------ 1 lock held by iou-wrk-366/368: #0: ffff0000c72598a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_ring_submit_lock+0x20/0x48 stack backtrace: CPU: 4 PID: 368 Comm: iou-wrk-366 Not tainted 5.18.0-rc6-00294-gdf8dc7004331 #994 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace.part.0+0xa4/0xd4 show_stack+0x14/0x5c dump_stack_lvl+0x88/0xb0 dump_stack+0x14/0x2c debug_check_no_locks_held+0x84/0x90 try_to_freeze.isra.0+0x18/0x44 get_signal+0x94/0x6ec io_wqe_worker+0x1d8/0x2b4 ret_from_fork+0x10/0x20 and triggering later hangs off get_signal() because we attempt to re-grab the lock. Reported-by: syzbot+987d7bb19195ae45208c@syzkaller.appspotmail.com Fixes: 149c69b04a90 ("io_uring: abstract out provided buffer list selection") Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.