Re: [PATCH] tee: shm: don't warn on an oversized page array in register_shm_helper()

[Sumit Garg <sumit.garg@kernel.org>]

On Tue, 03 Nov 2026 at 19:34:08 +0100, Jens Wiklander wrote:
>Hi,
>
>On Fri, Oct 23, 2026 at 11:03 PM Georgiy Osokin <g.osokin@auroraos.dev> wrote:
>>
>> register_shm_helper() sizes shm->pages from the length passed to
>> TEE_IOC_SHM_REGISTER and allocates it with kzalloc_objs(). A length above
>> 2 GiB makes the array larger than the page allocator can serve in one
>> block (MAX_PAGE_ORDER), so it trips its order warning; on a panic_on_warn
>> kernel that is a panic.
>>
>> The size comes from userspace and the request fails with -ENOMEM anyway,
>> so pass __GFP_NOWARN. kvzalloc_objs() would not help since kvmalloc
>> warns above INT_MAX as well.
>>
>> Fixes: 033ddf12bcf5 ("tee: add register user memory")
>> Cc: stable@vger.kernel.org
>> Cc: lvc-project@linuxtesting.org
>> Signed-off-by: Georgiy Osokin <g.osokin@auroraos.dev>
>> ---
>>  drivers/tee/tee_shm.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
>> index 6742b35..d539988 100644
>> --- a/drivers/tee/tee_shm.c
>> +++ b/drivers/tee/tee_shm.c
>> @@ -438,7 +438,8 @@ register_shm_helper(struct tee_context *ctx, struct iov_iter *iter, u32 flags,
>>                 goto err_free_shm;
>>         }
>>
>> -       shm->pages = kzalloc_objs(*shm->pages, num_pages);
>> +       shm->pages = kzalloc_objs(*shm->pages, num_pages,
>> +                                 GFP_KERNEL | __GFP_NOWARN);
>>         if (!shm->pages) {
>>                 ret = ERR_PTR(-ENOMEM);
>>                 goto err_free_shm;
>>
>> base-commit: 72d3fcf802c45d00b300f25b848a93c3a2bd7c7e
>> --
>> 2.54.0
>>
>
>Looks good. Sumit, do you agree?

Yeah, feel free to add:

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit