On Thu, 8 Jun 2023 at 06:11, Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> wrote: > > If function pwrdm_read_prev_pwrst() returns -EINVAL, we will end > up accessing array pwrdm->state_counter through negative index > -22. This is wrong and the compiler is legitimately warning us > about this potential problem. > > Fix this by sanity checking the value stored in variable _prev_ > before accessing array pwrdm->state_counter. > > Address the following -Warray-bounds warning: > arch/arm/mach-omap2/powerdomain.c:178:45: warning: array subscript -22 is below array bounds of 'unsigned int[4]' [-Warray-bounds] > > Link: https://github.com/KSPP/linux/issues/307 > Fixes: ba20bb126940 ("OMAP: PM counter infrastructure.") > Cc: stable@xxxxxxxxxxxxxxx > Reported-by: kernel test robot <lkp@xxxxxxxxx> > Link: https://lore.kernel.org/lkml/20230607050639.LzbPn%25lkp@xxxxxxxxx/ > Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> Nice to see this work paying off. Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx> Does the error case need further handling here? > --- > arch/arm/mach-omap2/powerdomain.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c > index 777f9f8e7cd8..5e05dd1324e7 100644 > --- a/arch/arm/mach-omap2/powerdomain.c > +++ b/arch/arm/mach-omap2/powerdomain.c > @@ -174,7 +174,7 @@ static int _pwrdm_state_switch(struct powerdomain *pwrdm, int flag) > break; > case PWRDM_STATE_PREV: > prev = pwrdm_read_prev_pwrst(pwrdm); > - if (pwrdm->state != prev) > + if (prev >= 0 && pwrdm->state != prev) > pwrdm->state_counter[prev]++; > if (prev == PWRDM_POWER_RET) > _update_logic_membank_counters(pwrdm); > -- > 2.34.1 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
