tree 21d8b2575f063a684a61fb8af4a9ecb456eb38a6
parent f9454f9e953871fa6dc191c7f4a4e619e6fd5a5f
author Bing-Jhong Billy Jheng <billy@starlabs.sg> 1677762006 +0800
committer Meena Shanmugam <meenashanmugam@google.com> 1681875032 +0000

io_uring: add missing lock in io_get_file_fixed

io_get_file_fixed will access io_uring's context. Lock it if it is
invoked unlocked (eg via io-wq) to avoid a race condition with fixed
files getting unregistered.

No single upstream patch exists for this issue, it was fixed as part
of the file assignment changes that went into the 5.18 cycle.

BUG=b/277048957,b/277623285
TEST=presubmit,validation
RELEASE_NOTE=Fixed race condition in io_uring in the Linux kernel.

Signed-off-by: Jheng, Bing-Jhong Billy <billy@starlabs.sg>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cos-patch: security-moderate
Change-Id: Ic723f1e66b5c0b4a3b8cfb9548bcc9465ce02fed
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/46467
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Vaibhav Rustagi <vaibhavrustagi@google.com>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/46927