Re: [PATCH] irqchip/riscv-imsic: Fix MMIO regset lookup loop bound

From: Guo Ren

Date: Fri Sep 04 2026 - 10:48:23 EST


Sorry, I didn't notice this:

https://lore.kernel.org/linux-riscv/20260718033646.001.7e022554-caplitmus-rv@xxxxxxxxxxx/

Please abandon this patch.

On Fri, Sep 4, 2026 at 10:32 PM GUO Ren (XuanTie) <guoren@xxxxxxxxxx> wrote:
>
> The nr_mmios is the number of entries in the MMIO resource array, while
> j is the index used to iterate over the array. Testing nr_mmios directly
> makes the loop condition permanently true whenever at least one MMIO
> region exists.
>
> So, change
> for (j = 0; nr_mmios; j++) {
> to
> for (j = 0; j < nr_mmios; j++) {
>
> Fixes: 21a8f8a0eb35 ("irqchip: Add RISC-V incoming MSI controller early driver")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: GUO Ren (XuanTie) <guoren@xxxxxxxxxx>
> ---
> This patch fixes an out-of-bounds access in the RISC-V IMSIC MMIO
> resource lookup.
> ---
> drivers/irqchip/irq-riscv-imsic-state.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/irqchip/irq-riscv-imsic-state.c b/drivers/irqchip/irq-riscv-imsic-state.c
> index b8d1bbbf42f7..008dfcf343e5 100644
> --- a/drivers/irqchip/irq-riscv-imsic-state.c
> +++ b/drivers/irqchip/irq-riscv-imsic-state.c
> @@ -896,7 +896,7 @@ int __init imsic_setup_state(struct fwnode_handle *fwnode, void *opaque)
> index = nr_mmios;
> reloff = i * BIT(global->guest_index_bits) *
> IMSIC_MMIO_PAGE_SZ;
> - for (j = 0; nr_mmios; j++) {
> + for (j = 0; j < nr_mmios; j++) {
> if (reloff < resource_size(&mmios[j])) {
> index = j;
> break;
>
> ---
> base-commit: bc35965f6940a9bf834d54187b6088b8eb09206d
> change-id: 20260904-nr_mmios-868e369de25b
>
> Best regards,
> --
> GUO Ren (XuanTie) <guoren@xxxxxxxxxx>
>

--
Best Regards
Guo Ren