| Message ID | 1449057508-10172-1-git-send-email-colin.king@canonical.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
CCing authors too. On Wed, Dec 02, 2015 at 11:58:28AM +0000, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > > There is a check to see if extlog_l1_addr is null before calling > acpi_os_unmap_iomem, however, before that call there is a > dereference on this that could trip an oops. Move the > extlog_l1_addr dereference so it occurs only if it is not null. > > Found by static analysis by smatch. > > Signed-off-by: Colin Ian King <colin.king@canonical.com> > --- > drivers/acpi/acpi_extlog.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/acpi_extlog.c b/drivers/acpi/acpi_extlog.c > index b3842ff..183b7b2 100644 > --- a/drivers/acpi/acpi_extlog.c > +++ b/drivers/acpi/acpi_extlog.c > @@ -309,9 +309,10 @@ static void __exit extlog_exit(void) > { > set_edac_report_status(old_edac_report_status); > mce_unregister_decode_chain(&extlog_mce_dec); > - ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; > - if (extlog_l1_addr) > + if (extlog_l1_addr) { > + ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; > acpi_os_unmap_iomem(extlog_l1_addr, l1_size); > + } > if (elog_addr) > acpi_os_unmap_iomem(elog_addr, elog_size); > release_mem_region(elog_base, elog_size); > -- > 2.6.2 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >
diff --git a/drivers/acpi/acpi_extlog.c b/drivers/acpi/acpi_extlog.c index b3842ff..183b7b2 100644 --- a/drivers/acpi/acpi_extlog.c +++ b/drivers/acpi/acpi_extlog.c @@ -309,9 +309,10 @@ static void __exit extlog_exit(void) { set_edac_report_status(old_edac_report_status); mce_unregister_decode_chain(&extlog_mce_dec); - ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; - if (extlog_l1_addr) + if (extlog_l1_addr) { + ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; acpi_os_unmap_iomem(extlog_l1_addr, l1_size); + } if (elog_addr) acpi_os_unmap_iomem(elog_addr, elog_size); release_mem_region(elog_base, elog_size);