From: Jens Wiklander <jens.wiklander@linaro.org>
To: Xiaolei Wang <xiaolei.wang@windriver.com>
Cc: sumit.garg@linaro.org, op-tee@lists.trustedfirmware.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] optee: Suppress false positive kmemleak report in optee_handle_rpc()
Date: Wed, 15 Dec 2021 13:29:12 +0100 [thread overview]
Message-ID: <20211215122912.GA1874103@jade> (raw)
In-Reply-To: <20211206120533.602062-1-xiaolei.wang@windriver.com>
On Mon, Dec 06, 2021 at 08:05:33PM +0800, Xiaolei Wang wrote:
> We observed the following kmemleak report:
> unreferenced object 0xffff000007904500 (size 128):
> comm "swapper/0", pid 1, jiffies 4294892671 (age 44.036s)
> hex dump (first 32 bytes):
> 00 47 90 07 00 00 ff ff 60 00 c0 ff 00 00 00 00 .G......`.......
> 60 00 80 13 00 80 ff ff a0 00 00 00 00 00 00 00 `...............
> backtrace:
> [<000000004c12b1c7>] kmem_cache_alloc+0x1ac/0x2f4
> [<000000005d23eb4f>] tee_shm_alloc+0x78/0x230
> [<00000000794dd22c>] optee_handle_rpc+0x60/0x6f0
> [<00000000d9f7c52d>] optee_do_call_with_arg+0x17c/0x1dc
> [<00000000c35884da>] optee_open_session+0x128/0x1ec
> [<000000001748f2ff>] tee_client_open_session+0x28/0x40
> [<00000000aecb5389>] optee_enumerate_devices+0x84/0x2a0
> [<000000003df18bf1>] optee_probe+0x674/0x6cc
> [<000000003a4a534a>] platform_drv_probe+0x54/0xb0
> [<000000000c51ce7d>] really_probe+0xe4/0x4d0
> [<000000002f04c865>] driver_probe_device+0x58/0xc0
> [<00000000b485397d>] device_driver_attach+0xc0/0xd0
> [<00000000c835f0df>] __driver_attach+0x84/0x124
> [<000000008e5a429c>] bus_for_each_dev+0x70/0xc0
> [<000000001735e8a8>] driver_attach+0x24/0x30
> [<000000006d94b04f>] bus_add_driver+0x104/0x1ec
>
> This is not a memory leak because we pass the share memory pointer
> to secure world and would get it from secure world before releasing it.
>
> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
> ---
> drivers/tee/optee/smc_abi.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
> index 6196d7c3888f..cf2e3293567d 100644
> --- a/drivers/tee/optee/smc_abi.c
> +++ b/drivers/tee/optee/smc_abi.c
> @@ -23,6 +23,7 @@
> #include "optee_private.h"
> #include "optee_smc.h"
> #include "optee_rpc_cmd.h"
> +#include <linux/kmemleak.h>
> #define CREATE_TRACE_POINTS
> #include "optee_trace.h"
>
> @@ -783,6 +784,7 @@ static void optee_handle_rpc(struct tee_context *ctx,
> param->a4 = 0;
> param->a5 = 0;
> }
> + kmemleak_not_leak(shm);
Eventually this pointer will be freed below with the call to tee_shm_free().
I assume than once the memory is freed it's not execused from being a leak
any longer. Is that correct?
Thanks,
Jens
> break;
> case OPTEE_SMC_RPC_FUNC_FREE:
> shm = reg_pair_to_ptr(param->a1, param->a2);
> --
> 2.25.1
>
next prev parent reply other threads:[~2021-12-15 12:29 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-06 12:05 [PATCH] optee: Suppress false positive kmemleak report in optee_handle_rpc() Xiaolei Wang
2021-12-09 11:40 ` Sumit Garg
2021-12-10 4:12 ` Wang, Xiaolei
2021-12-10 5:00 ` Sumit Garg
2021-12-10 8:10 ` Jerome Forissier
2021-12-10 9:38 ` Etienne Carriere
2021-12-10 9:43 ` Etienne Carriere
2021-12-10 10:28 ` Sumit Garg
2021-12-10 10:39 ` Etienne Carriere
2021-12-10 10:41 ` Jens Wiklander
2021-12-10 9:38 ` Sumit Garg
2021-12-10 15:49 ` Daniel Thompson
2021-12-13 8:58 ` Sumit Garg
2021-12-13 13:04 ` Daniel Thompson
2021-12-14 7:03 ` Sumit Garg
2021-12-15 10:19 ` Daniel Thompson
2021-12-15 12:25 ` Jens Wiklander
2021-12-15 13:42 ` Sumit Garg
2021-12-13 8:55 ` wangxiaolei
2021-12-13 9:04 ` Sumit Garg
2021-12-14 7:11 ` wangxiaolei
2021-12-14 7:29 ` Sumit Garg
2021-12-14 7:41 ` wangxiaolei
2021-12-15 12:29 ` Jens Wiklander [this message]
2021-12-15 13:33 ` Wang, Xiaolei
2021-12-16 14:55 ` Jens Wiklander
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