Thread (72 messages) 72 messages, 9 authors, 2019-06-12

Re: [PATCH v16 14/16] tee, arm64: untag user pointers in tee_shm_register

From: Jens Wiklander <jens.wiklander@linaro.org>
Date: 2019-06-07 05:33:51
Also in: amd-gfx, dri-devel, kvm, linux-kselftest, linux-media, linux-mm, linux-rdma, lkml

On Mon, Jun 3, 2019 at 6:56 PM Andrey Konovalov [off-list ref] 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.

tee_shm_register()->optee_shm_unregister()->check_mem_type() uses provided
user pointers for vma lookups (via __check_mem_type()), which can only by
done with untagged pointers.

Untag user pointers in this function.

Signed-off-by: Andrey Konovalov <redacted>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>
quoted hunk ↗ jump to hunk
---
 drivers/tee/tee_shm.c | 1 +
 1 file changed, 1 insertion(+)
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
index 49fd7312e2aa..96945f4cefb8 100644
--- a/drivers/tee/tee_shm.c
+++ b/drivers/tee/tee_shm.c
@@ -263,6 +263,7 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr,
        shm->teedev = teedev;
        shm->ctx = ctx;
        shm->id = -1;
+       addr = untagged_addr(addr);
        start = rounddown(addr, PAGE_SIZE);
        shm->offset = addr - start;
        shm->size = length;
--
2.22.0.rc1.311.g5d7573a151-goog
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help