On Wed, Jun 25, 2025 at 11:43 PM Colin King (gmail)
<colin.i.king@xxxxxxxxx> wrote:
>
> On 25/06/2025 22:40, Ira Weiny wrote:
> > Colin Ian King wrote:
> >> In the case where a request_mem_region call fails and pointer r is null
> >> the error exit path via label 'out' will check for a non-null pointer
> >> p and try to iounmap it. However, pointer p has not been assigned a
> >> value at this point, so it may potentially contain any garbage value.
> >> Fix this by ensuring pointer p is initialized to NULL.
> >>
> >> Fixes: 1a35c88302a3 ("ACPI: APEI: EINJ: Fix kernel test sparse warnings")
> >> Signed-off-by: Colin Ian King <colin.i.king@xxxxxxxxx>
> >> ---
> >> drivers/acpi/apei/einj-core.c | 2 +-
> >> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/acpi/apei/einj-core.c b/drivers/acpi/apei/einj-core.c
> >> index 7930acd1d3f3..fc801587df8e 100644
> >> --- a/drivers/acpi/apei/einj-core.c
> >> +++ b/drivers/acpi/apei/einj-core.c
> >> @@ -401,7 +401,7 @@ static int __einj_error_trigger(u64 trigger_paddr, u32 type,
> >> u32 table_size;
> >> int rc = -EIO;
> >> struct acpi_generic_address *trigger_param_region = NULL;
> >> - struct acpi_einj_trigger __iomem *p;
> >> + struct acpi_einj_trigger __iomem *p = NULL;
> >
> > Apparently my review of these was pretty weak... :-/
> >
> > That said; Why not skip a goto as well?
>
> Because the goto uses a shared return path and hence reduces the amount
> of return epilogue used in the generated code.
Applied, thanks!
> > diff --git a/drivers/acpi/apei/einj-core.c b/drivers/acpi/apei/einj-core.c
> > index d6d7e36e3647..fae01795e7f6 100644
> > --- a/drivers/acpi/apei/einj-core.c
> > +++ b/drivers/acpi/apei/einj-core.c
> > @@ -410,7 +410,7 @@ static int __einj_error_trigger(u64 trigger_paddr, u32 type,
> > (unsigned long long)trigger_paddr,
> > (unsigned long long)trigger_paddr +
> > sizeof(trigger_tab) - 1);
> > - goto out;
> > + return -EIO;
> > }
> > p = ioremap_cache(trigger_paddr, sizeof(*p));
> > if (!p) {
> > @@ -502,7 +502,6 @@ static int __einj_error_trigger(u64 trigger_paddr, u32 type,
> > table_size - sizeof(trigger_tab));
> > out_rel_header:
> > release_mem_region(trigger_paddr, sizeof(trigger_tab));
> > -out:
> > if (p)
> > iounmap(p);
> >
>
