2023-03-01 16:31:23

by Sasha Levin

[permalink] [raw]
Subject: [PATCH AUTOSEL 5.4 1/4] tracing: Add NULL checks for buffer in ring_buffer_free_read_page()

From: Jia-Ju Bai <[email protected]>

[ Upstream commit 3e4272b9954094907f16861199728f14002fcaf6 ]

In a previous commit 7433632c9ff6, buffer, buffer->buffers and
buffer->buffers[cpu] in ring_buffer_wake_waiters() can be NULL,
and thus the related checks are added.

However, in the same call stack, these variables are also used in
ring_buffer_free_read_page():

tracing_buffers_release()
ring_buffer_wake_waiters(iter->array_buffer->buffer)
cpu_buffer = buffer->buffers[cpu] -> Add checks by previous commit
ring_buffer_free_read_page(iter->array_buffer->buffer)
cpu_buffer = buffer->buffers[cpu] -> No check

Thus, to avod possible null-pointer derefernces, the related checks
should be added.

These results are reported by a static tool designed by myself.

Link: https://lkml.kernel.org/r/[email protected]

Reported-by: TOTE Robot <[email protected]>
Signed-off-by: Jia-Ju Bai <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
kernel/trace/ring_buffer.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 11e8189dd8ae9..58809fffc8171 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -4769,11 +4769,16 @@ EXPORT_SYMBOL_GPL(ring_buffer_alloc_read_page);
*/
void ring_buffer_free_read_page(struct ring_buffer *buffer, int cpu, void *data)
{
- struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu];
+ struct ring_buffer_per_cpu *cpu_buffer;
struct buffer_data_page *bpage = data;
struct page *page = virt_to_page(bpage);
unsigned long flags;

+ if (!buffer || !buffer->buffers || !buffer->buffers[cpu])
+ return;
+
+ cpu_buffer = buffer->buffers[cpu];
+
/* If the page is still in use someplace else, we can't reuse it */
if (page_ref_count(page) > 1)
goto out;
--
2.39.2



2023-03-01 16:31:30

by Sasha Levin

[permalink] [raw]
Subject: [PATCH AUTOSEL 5.4 2/4] efi: efivars: prevent double registration

From: Johan Hovold <[email protected]>

[ Upstream commit 0217a40d7ba6e71d7f3422fbe89b436e8ee7ece7 ]

Add the missing sanity check to efivars_register() so that it is no
longer possible to override an already registered set of efivar ops
(without first deregistering them).

This can help debug initialisation ordering issues where drivers have so
far unknowingly been relying on overriding the generic ops.

Signed-off-by: Johan Hovold <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
drivers/firmware/efi/vars.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index a32d15b2928f7..87cbcbea40e90 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -1182,19 +1182,28 @@ int efivars_register(struct efivars *efivars,
const struct efivar_operations *ops,
struct kobject *kobject)
{
+ int rv;
+
if (down_interruptible(&efivars_lock))
return -EINTR;

+ if (__efivars) {
+ pr_warn("efivars already registered\n");
+ rv = -EBUSY;
+ goto out;
+ }
+
efivars->ops = ops;
efivars->kobject = kobject;

__efivars = efivars;

pr_info("Registered efivars operations\n");
-
+ rv = 0;
+out:
up(&efivars_lock);

- return 0;
+ return rv;
}
EXPORT_SYMBOL_GPL(efivars_register);

--
2.39.2


2023-03-01 16:31:32

by Sasha Levin

[permalink] [raw]
Subject: [PATCH AUTOSEL 5.4 3/4] firmware/efi sysfb_efi: Add quirk for Lenovo IdeaPad Duet 3

From: Darrell Kavanagh <[email protected]>

[ Upstream commit e1d447157f232c650e6f32c9fb89ff3d0207c69a ]

Another Lenovo convertable which reports a landscape resolution of
1920x1200 with a pitch of (1920 * 4) bytes, while the actual framebuffer
has a resolution of 1200x1920 with a pitch of (1200 * 4) bytes.

Signed-off-by: Darrell Kavanagh <[email protected]>
Reviewed-by: Hans de Goede <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
arch/x86/kernel/sysfb_efi.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/arch/x86/kernel/sysfb_efi.c b/arch/x86/kernel/sysfb_efi.c
index 653b7f617b61b..9ea65611fba0b 100644
--- a/arch/x86/kernel/sysfb_efi.c
+++ b/arch/x86/kernel/sysfb_efi.c
@@ -264,6 +264,14 @@ static const struct dmi_system_id efifb_dmi_swap_width_height[] __initconst = {
"Lenovo ideapad D330-10IGM"),
},
},
+ {
+ /* Lenovo IdeaPad Duet 3 10IGL5 with 1200x1920 portrait screen */
+ .matches = {
+ DMI_EXACT_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_EXACT_MATCH(DMI_PRODUCT_VERSION,
+ "IdeaPad Duet 3 10IGL5"),
+ },
+ },
{},
};

--
2.39.2


2023-03-01 16:31:40

by Sasha Levin

[permalink] [raw]
Subject: [PATCH AUTOSEL 5.4 4/4] mfd: arizona: Use pm_runtime_resume_and_get() to prevent refcnt leak

From: Liang He <[email protected]>

[ Upstream commit 4414a7ab80cebf715045e3c4d465feefbad21139 ]

In arizona_clk32k_enable(), we should use pm_runtime_resume_and_get()
as pm_runtime_get_sync() will increase the refcnt even when it
returns an error.

Signed-off-by: Liang He <[email protected]>
Acked-by: Charles Keepax <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
---
drivers/mfd/arizona-core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mfd/arizona-core.c b/drivers/mfd/arizona-core.c
index 3ff872c205eeb..07d256e6875c0 100644
--- a/drivers/mfd/arizona-core.c
+++ b/drivers/mfd/arizona-core.c
@@ -45,7 +45,7 @@ int arizona_clk32k_enable(struct arizona *arizona)
if (arizona->clk32k_ref == 1) {
switch (arizona->pdata.clk32k_src) {
case ARIZONA_32KZ_MCLK1:
- ret = pm_runtime_get_sync(arizona->dev);
+ ret = pm_runtime_resume_and_get(arizona->dev);
if (ret != 0)
goto err_ref;
ret = clk_prepare_enable(arizona->mclk[ARIZONA_MCLK1]);
--
2.39.2


2023-03-01 16:34:08

by Ard Biesheuvel

[permalink] [raw]
Subject: Re: [PATCH AUTOSEL 5.4 2/4] efi: efivars: prevent double registration

On Wed, 1 Mar 2023 at 17:30, Sasha Levin <[email protected]> wrote:
>
> From: Johan Hovold <[email protected]>
>
> [ Upstream commit 0217a40d7ba6e71d7f3422fbe89b436e8ee7ece7 ]
>
> Add the missing sanity check to efivars_register() so that it is no
> longer possible to override an already registered set of efivar ops
> (without first deregistering them).
>
> This can help debug initialisation ordering issues where drivers have so
> far unknowingly been relying on overriding the generic ops.
>
> Signed-off-by: Johan Hovold <[email protected]>
> Signed-off-by: Ard Biesheuvel <[email protected]>
> Signed-off-by: Sasha Levin <[email protected]>

NAK this is not a bugfix.

> ---
> drivers/firmware/efi/vars.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
> index a32d15b2928f7..87cbcbea40e90 100644
> --- a/drivers/firmware/efi/vars.c
> +++ b/drivers/firmware/efi/vars.c
> @@ -1182,19 +1182,28 @@ int efivars_register(struct efivars *efivars,
> const struct efivar_operations *ops,
> struct kobject *kobject)
> {
> + int rv;
> +
> if (down_interruptible(&efivars_lock))
> return -EINTR;
>
> + if (__efivars) {
> + pr_warn("efivars already registered\n");
> + rv = -EBUSY;
> + goto out;
> + }
> +
> efivars->ops = ops;
> efivars->kobject = kobject;
>
> __efivars = efivars;
>
> pr_info("Registered efivars operations\n");
> -
> + rv = 0;
> +out:
> up(&efivars_lock);
>
> - return 0;
> + return rv;
> }
> EXPORT_SYMBOL_GPL(efivars_register);
>
> --
> 2.39.2
>