Re: [PATCH] hw/ufs: Fix potential bugs in MMIO read|write

[Jeuk Kim <jeuk20.kim@gmail.com>]

On 6/24/2024 7:27 PM, Peter Maydell wrote:
> On Sun, 23 Jun 2024 at 03:46, Minwoo Im <minwoo.im.dev@gmail.com> wrote:
>> This patch fixes two points reported in coverity scan report [1].  Check
>> the MMIO access address with (addr + size), not just with the start offset
>> addr to make sure that the requested memory access not to exceed the
>> actual register region.  We also updated (uint8_t *) to (uint32_t *) to
>> represent we are accessing the MMIO registers by dword-sized only.
>>
>> [1] https://lore.kernel.org/qemu-devel/CAFEAcA82L-WZnHMW0X+Dr40bHM-EVq2ZH4DG4pdqop4xxDP2Og@mail.gmail.com/
>>
>> Cc: Jeuk Kim <jeuk20.kim@gmail.com>
>> Reported-by: Peter Maydell <peter.maydell@linaro.org>
>> Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
>> ---
>>   hw/ufs/ufs.c | 31 ++++++++++++++++---------------
>>   1 file changed, 16 insertions(+), 15 deletions(-)
>>
>> diff --git a/hw/ufs/ufs.c b/hw/ufs/ufs.c
>> index 71a88d221ced..bf2ff02ac6e5 100644
>> --- a/hw/ufs/ufs.c
>> +++ b/hw/ufs/ufs.c
>> @@ -55,17 +55,18 @@ static inline uint64_t ufs_reg_size(UfsHc *u)
>>       return ufs_mcq_op_reg_addr(u, 0) + sizeof(u->mcq_op_reg);
>>   }
>>
>> -static inline bool ufs_is_mcq_reg(UfsHc *u, uint64_t addr)
>> +static inline bool ufs_is_mcq_reg(UfsHc *u, uint64_t addr, unsigned size)
>>   {
>>       uint64_t mcq_reg_addr = ufs_mcq_reg_addr(u, 0);
>> -    return addr >= mcq_reg_addr && addr < mcq_reg_addr + sizeof(u->mcq_reg);
>> +    return (addr >= mcq_reg_addr &&
>> +            addr + size <= mcq_reg_addr + sizeof(u->mcq_reg));
>>   }
>>
>> -static inline bool ufs_is_mcq_op_reg(UfsHc *u, uint64_t addr)
>> +static inline bool ufs_is_mcq_op_reg(UfsHc *u, uint64_t addr, unsigned size)
>>   {
>>       uint64_t mcq_op_reg_addr = ufs_mcq_op_reg_addr(u, 0);
>>       return (addr >= mcq_op_reg_addr &&
>> -            addr < mcq_op_reg_addr + sizeof(u->mcq_op_reg));
>> +            addr  + size <= mcq_op_reg_addr + sizeof(u->mcq_op_reg));
> Stray extra space after "addr".

Thank you for your comment.

I'll fix it when I send the pull request.

>
> Otherwise
> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
>
> thanks
> -- PMM