[PATCH AUTOSEL 4.14 1/3] tracing: Add NULL checks for buffer in ring_buffer_free_read_page()
From: Jia-Ju Bai baijiaju1990@gmail.com
[ 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/20230113125501.760324-1-baijiaju1990@gmail.com
Reported-by: TOTE Robot oslab@tsinghua.edu.cn Signed-off-by: Jia-Ju Bai baijiaju1990@gmail.com Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 999dae39f12e5..a7808f8b6f56a 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -4554,11 +4554,16 @@ 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;
From: Johan Hovold johan+linaro@kernel.org
[ 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 johan+linaro@kernel.org Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 e619ced030d52..462e88b9d2ba4 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -1195,19 +1195,28 @@ 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);
On Wed, 1 Mar 2023 at 17:30, Sasha Levin sashal@kernel.org wrote:
From: Johan Hovold johan+linaro@kernel.org
[ 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 johan+linaro@kernel.org Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org
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 e619ced030d52..462e88b9d2ba4 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -1195,19 +1195,28 @@ 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
From: Darrell Kavanagh darrell.kavanagh@gmail.com
[ 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 darrell.kavanagh@gmail.com Reviewed-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 897da526e40e6..dd8d7636c5420 100644 --- a/arch/x86/kernel/sysfb_efi.c +++ b/arch/x86/kernel/sysfb_efi.c @@ -265,6 +265,14 @@ 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"), + }, + }, {}, };
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