On 6/3/19 10:55 AM, Andrey Konovalov wrote:
This patch is a part of a series that extends arm64 kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments.
do_pages_move() is used in the implementation of the move_pages syscall.
Untag user pointers in this function.
Reviewed-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Andrey Konovalov andreyknvl@google.com
mm/migrate.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/mm/migrate.c b/mm/migrate.c index f2ecc2855a12..3930bb6fa656 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1617,6 +1617,7 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, if (get_user(node, nodes + i)) goto out_flush; addr = (unsigned long)p;
addr = untagged_addr(addr);
Why not just "addr = (unsigned long)untagged_addr(p);"
-- Khalid