From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Subject: drm/radeon: untag user pointers in radeon_gem_userptr_ioctl This patch is a part of a series that extends kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments. In radeon_gem_userptr_ioctl() an MMU notifier is set up with a (tagged) userspace pointer. The untagged address should be used so that MMU notifiers for the untagged address get correctly matched up with the right BO. This funcation also calls radeon_ttm_tt_pin_userptr(), which uses provided user pointers for vma lookups, which can only by done with untagged pointers. This patch untags user pointers in radeon_gem_userptr_ioctl(). Link: http://lkml.kernel.org/r/c856babeb67195b35603b8d5ba386a2819cec5ff.1563904656.git.andreyknvl@xxxxxxxxxx Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Reviewed-by: Khalid Aziz <khalid.aziz@xxxxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> Suggested-by: Felix Kuehling <Felix.Kuehling@xxxxxxx> Acked-by: Felix Kuehling <Felix.Kuehling@xxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: Eric Auger <eric.auger@xxxxxxxxxx> Cc: Jens Wiklander <jens.wiklander@xxxxxxxxxx> Cc: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx> Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/radeon/radeon_gem.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/gpu/drm/radeon/radeon_gem.c~drm-radeon-untag-user-pointers-in-radeon_gem_userptr_ioctl +++ a/drivers/gpu/drm/radeon/radeon_gem.c @@ -296,6 +296,8 @@ int radeon_gem_userptr_ioctl(struct drm_ uint32_t handle; int r; + args->addr = untagged_addr(args->addr); + if (offset_in_page(args->addr | args->size)) return -EINVAL; _
