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

[Peter Maydell]

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] 
> CAFEAcA82L-WZnHMW0X+Dr40bHM-EVq2ZH4DG4pdqop4xxDP2Og@mail.gmail.com/">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".

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

thanks
-- PMM