powerpc/powernv/vas: Release reference to tgid during window close

The kernel handles the NX fault by updating CSB or sending
signal to process. In multithread applications, children can
open VAS windows and can exit without closing them. But the
parent can continue to send NX requests with these windows. To
prevent pid reuse, reference will be taken on pid and tgid
when the window is opened and release them during window close.

The current code is not releasing the tgid reference which can
cause pid leak and this patch fixes the issue.

Fixes: db1c08a740635 ("powerpc/vas: Take reference to PID and mm for user space windows")
Cc: [email protected] # 5.8+
Reported-by: Nicholas Piggin <[email protected]>
Signed-off-by: Haren Myneni <[email protected]>
Reviewed-by: Nicholas Piggin <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

0 files changed, 0 insertions, 0 deletions