4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Frederic Barrat <fbarrat@xxxxxxxxxxxxxxxxxx>
commit cec422c11caeeccae709e9942058b6b644ce434c upstream.
Fix error path if we can't copy user structure on CXL_IOCTL_START_WORK
ioctl. We shouldn't unlock the context status mutex as it was not
locked (yet).
Fixes: 0712dc7e73e5 ("cxl: Fix issues when unmapping contexts")
Signed-off-by: Frederic Barrat <fbarrat@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Vaibhav Jain <vaibhav@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Andrew Donnellan <andrew.donnellan@xxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/misc/cxl/file.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
--- a/drivers/misc/cxl/file.c
+++ b/drivers/misc/cxl/file.c
@@ -158,11 +158,8 @@ static long afu_ioctl_start_work(struct
/* Do this outside the status_mutex to avoid a circular dependency with
* the locking in cxl_mmap_fault() */
- if (copy_from_user(&work, uwork,
- sizeof(struct cxl_ioctl_start_work))) {
- rc = -EFAULT;
- goto out;
- }
+ if (copy_from_user(&work, uwork, sizeof(work)))
+ return -EFAULT;
mutex_lock(&ctx->status_mutex);
if (ctx->status != OPENED) {