When CONFIG_FORTIFY_SOURCE is set, memcpy() checks the potential
buffer overflow and panics. The code in sofcpga bootstrapping
contains the memcpy() calls are mistakenly translated as the shorter
size, hence it triggers a panic as if it were overflowing.
This patch adds the __NO_FORTIFY define for avoiding the
false-positive crash.
Buglink: https://bugzilla.suse.com/show_bug.cgi?id=1192473
Signed-off-by: Takashi Iwai <[email protected]>
---
I took an easier path for now, as the attempt with a foced cast
failed. If there is a better way to handle, let me know, I'd happily
resubmit. Thanks!
arch/arm/mach-socfpga/platsmp.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/arm/mach-socfpga/platsmp.c b/arch/arm/mach-socfpga/platsmp.c
index fbb80b883e5d..d46b1af96a8a 100644
--- a/arch/arm/mach-socfpga/platsmp.c
+++ b/arch/arm/mach-socfpga/platsmp.c
@@ -5,6 +5,9 @@
* Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
* Copyright (C) 2012 Altera Corporation
*/
+
+#define __NO_FORTIFY /* need to avoid the crash with memcpy() calls */
+
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/smp.h>
--
2.26.2
On Wed, Nov 17, 2021 at 08:32:44PM +0100, Takashi Iwai wrote:
> When CONFIG_FORTIFY_SOURCE is set, memcpy() checks the potential
> buffer overflow and panics. The code in sofcpga bootstrapping
> contains the memcpy() calls are mistakenly translated as the shorter
> size, hence it triggers a panic as if it were overflowing.
>
> This patch adds the __NO_FORTIFY define for avoiding the
> false-positive crash.
>
> Buglink: https://bugzilla.suse.com/show_bug.cgi?id=1192473
> Signed-off-by: Takashi Iwai <[email protected]>
> ---
>
> I took an easier path for now, as the attempt with a foced cast
> failed. If there is a better way to handle, let me know, I'd happily
> resubmit. Thanks!
>
The way these have been fixed in the past is to declare these as char
arrays (see include/asm-generic/sections.h). I'd prefer something like
this (totally untested):
diff --git a/arch/arm/mach-socfpga/core.h b/arch/arm/mach-socfpga/core.h
index fc2608b18a0d..18f01190dcfd 100644
--- a/arch/arm/mach-socfpga/core.h
+++ b/arch/arm/mach-socfpga/core.h
@@ -33,7 +33,7 @@ extern void __iomem *sdr_ctl_base_addr;
u32 socfpga_sdram_self_refresh(u32 sdr_base);
extern unsigned int socfpga_sdram_self_refresh_sz;
-extern char secondary_trampoline, secondary_trampoline_end;
+extern char secondary_trampoline[], secondary_trampoline_end[];
extern unsigned long socfpga_cpu1start_addr;
diff --git a/arch/arm/mach-socfpga/platsmp.c b/arch/arm/mach-socfpga/platsmp.c
index fbb80b883e5d..201191cf68f3 100644
--- a/arch/arm/mach-socfpga/platsmp.c
+++ b/arch/arm/mach-socfpga/platsmp.c
@@ -20,14 +20,14 @@
static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
- int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
+ int trampoline_size = secondary_trampoline_end - secondary_trampoline;
if (socfpga_cpu1start_addr) {
/* This will put CPU #1 into reset. */
writel(RSTMGR_MPUMODRST_CPU1,
rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
- memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
+ memcpy(phys_to_virt(0), secondary_trampoline, trampoline_size);
writel(__pa_symbol(secondary_startup),
sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff));
@@ -45,12 +45,12 @@ static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
static int socfpga_a10_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
- int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
+ int trampoline_size = secondary_trampoline_end - secondary_trampoline;
if (socfpga_cpu1start_addr) {
writel(RSTMGR_MPUMODRST_CPU1, rst_manager_base_addr +
SOCFPGA_A10_RSTMGR_MODMPURST);
- memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
+ memcpy(phys_to_virt(0), secondary_trampoline, trampoline_size);
writel(__pa_symbol(secondary_startup),
sys_manager_base_addr + (socfpga_cpu1start_addr & 0x00000fff));
> arch/arm/mach-socfpga/platsmp.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/arm/mach-socfpga/platsmp.c b/arch/arm/mach-socfpga/platsmp.c
> index fbb80b883e5d..d46b1af96a8a 100644
> --- a/arch/arm/mach-socfpga/platsmp.c
> +++ b/arch/arm/mach-socfpga/platsmp.c
> @@ -5,6 +5,9 @@
> * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
> * Copyright (C) 2012 Altera Corporation
> */
> +
> +#define __NO_FORTIFY /* need to avoid the crash with memcpy() calls */
> +
> #include <linux/delay.h>
> #include <linux/init.h>
> #include <linux/smp.h>
> --
> 2.26.2
>
--
Kees Cook
On Wed, 17 Nov 2021 23:01:50 +0100,
Kees Cook wrote:
>
> On Wed, Nov 17, 2021 at 08:32:44PM +0100, Takashi Iwai wrote:
> > When CONFIG_FORTIFY_SOURCE is set, memcpy() checks the potential
> > buffer overflow and panics. The code in sofcpga bootstrapping
> > contains the memcpy() calls are mistakenly translated as the shorter
> > size, hence it triggers a panic as if it were overflowing.
> >
> > This patch adds the __NO_FORTIFY define for avoiding the
> > false-positive crash.
> >
> > Buglink: https://bugzilla.suse.com/show_bug.cgi?id=1192473
> > Signed-off-by: Takashi Iwai <[email protected]>
> > ---
> >
> > I took an easier path for now, as the attempt with a foced cast
> > failed. If there is a better way to handle, let me know, I'd happily
> > resubmit. Thanks!
> >
>
> The way these have been fixed in the past is to declare these as char
> arrays (see include/asm-generic/sections.h). I'd prefer something like
> this (totally untested):
(snip)
That looks better, indeed. I'll rebuild the kernel with it and ask
the bug reporter for testing it.
Thanks!
Takashi
On Thu, 18 Nov 2021 08:27:26 +0100,
Takashi Iwai wrote:
>
> On Wed, 17 Nov 2021 23:01:50 +0100,
> Kees Cook wrote:
> >
> > On Wed, Nov 17, 2021 at 08:32:44PM +0100, Takashi Iwai wrote:
> > > When CONFIG_FORTIFY_SOURCE is set, memcpy() checks the potential
> > > buffer overflow and panics. The code in sofcpga bootstrapping
> > > contains the memcpy() calls are mistakenly translated as the shorter
> > > size, hence it triggers a panic as if it were overflowing.
> > >
> > > This patch adds the __NO_FORTIFY define for avoiding the
> > > false-positive crash.
> > >
> > > Buglink: https://bugzilla.suse.com/show_bug.cgi?id=1192473
> > > Signed-off-by: Takashi Iwai <[email protected]>
> > > ---
> > >
> > > I took an easier path for now, as the attempt with a foced cast
> > > failed. If there is a better way to handle, let me know, I'd happily
> > > resubmit. Thanks!
> > >
> >
> > The way these have been fixed in the past is to declare these as char
> > arrays (see include/asm-generic/sections.h). I'd prefer something like
> > this (totally untested):
> (snip)
>
> That looks better, indeed. I'll rebuild the kernel with it and ask
> the bug reporter for testing it.
Confirmed to work. Will resubmit the v2 patch.
thanks,
Takashi