mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-08-30 23:59:33 -04:00
Code Issues Packages Projects Releases Wiki Activity

dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open()

Browse Source 
The failed_dev_add and failed_dev_name paths drop the file-device
reference while wq->wq_lock is still held. If put_device(fdev) drops the
last reference, idxd_file_dev_release() runs synchronously and tries to
take wq->wq_lock again, deadlocking.

Those paths also fall through into the later ctx cleanup labels even
though idxd_file_dev_release() owns that cleanup and frees ctx. This can
make idxd_xa_pasid_remove(ctx) and kfree(ctx) operate on a freed context.

Move idxd_wq_get() before file-device setup can fail, since the release
callback always calls idxd_wq_put(). Then unlock wq->wq_lock before
put_device(fdev) and return directly from the file-device setup failure
path, leaving ctx cleanup to the release callback.

Fixes: e6fd6d7e5f ("dmaengine: idxd: add a device to represent the file opened")
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Link: https://patch.msgid.link/20260525141550.1385581-1-dbgh9129@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Yuho Choi
2026-05-25 10:15:50 -04:00
committed by Vinod Koul
parent ec2d428b2e
commit ee1d727410
1 changed files with 3 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/dma/idxd/cdev.c
View File

@@ -288,6 +288,7 @@ static int idxd_cdev_open(struct inode *inode, struct file *filp)
fdev->parent = cdev_dev(idxd_cdev);
fdev->bus = &dsa_bus_type;
fdev->type = &idxd_cdev_file_type;
idxd_wq_get(wq);
rc = dev_set_name(fdev, "file%d", ctx->id);
if (rc < 0) {
@@ -301,13 +302,14 @@ static int idxd_cdev_open(struct inode *inode, struct file *filp)
goto failed_dev_add;
}
idxd_wq_get(wq);
mutex_unlock(&wq->wq_lock);
return 0;
failed_dev_add:
failed_dev_name:
mutex_unlock(&wq->wq_lock);
put_device(fdev);
return rc;
failed_ida:
failed_set_pasid:
if (device_user_pasid_enabled(idxd))