* [PATCH] kernel: initialize cpumask before parsing
@ 2021-04-01 5:58 Tetsuo Handa
2021-04-01 13:34 ` Steven Rostedt
2021-04-10 11:38 ` [tip: irq/core] kernel: Initialize " tip-bot2 for Tetsuo Handa
0 siblings, 2 replies; 3+ messages in thread
From: Tetsuo Handa @ 2021-04-01 5:58 UTC (permalink / raw)
To: Thomas Gleixner, Steven Rostedt, Ingo Molnar; +Cc: linux-kernel, Tetsuo Handa
KMSAN complains that new_value at cpumask_parse_user() from
write_irq_affinity() from irq_affinity_proc_write() is uninitialized.
[ 148.133411][ T5509] =====================================================
[ 148.135383][ T5509] BUG: KMSAN: uninit-value in find_next_bit+0x325/0x340
[ 148.137819][ T5509]
[ 148.138448][ T5509] Local variable ----new_value.i@irq_affinity_proc_write created at:
[ 148.140768][ T5509] irq_affinity_proc_write+0xc3/0x3d0
[ 148.142298][ T5509] irq_affinity_proc_write+0xc3/0x3d0
[ 148.143823][ T5509] =====================================================
Since bitmap_parse() from cpumask_parse_user() calls find_next_bit(),
any alloc_cpumask_var() + cpumask_parse_user() sequence has possibility
that find_next_bit() accesses uninitialized cpu mask variable. Fix this
problem by replacing alloc_cpumask_var() with zalloc_cpumask_var().
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
---
kernel/irq/proc.c | 4 ++--
kernel/profile.c | 2 +-
kernel/trace/trace.c | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 98138788cb04..7c5cd42df3b9 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -144,7 +144,7 @@ static ssize_t write_irq_affinity(int type, struct file *file,
if (!irq_can_set_affinity_usr(irq) || no_irq_affinity)
return -EIO;
- if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&new_value, GFP_KERNEL))
return -ENOMEM;
if (type)
@@ -238,7 +238,7 @@ static ssize_t default_affinity_write(struct file *file,
cpumask_var_t new_value;
int err;
- if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&new_value, GFP_KERNEL))
return -ENOMEM;
err = cpumask_parse_user(buffer, count, new_value);
diff --git a/kernel/profile.c b/kernel/profile.c
index 6f69a4195d56..c2ebddb5e974 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -430,7 +430,7 @@ static ssize_t prof_cpu_mask_proc_write(struct file *file,
cpumask_var_t new_value;
int err;
- if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&new_value, GFP_KERNEL))
return -ENOMEM;
err = cpumask_parse_user(buffer, count, new_value);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index eccb4e1187cc..7607dc8a20b2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4827,7 +4827,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
cpumask_var_t tracing_cpumask_new;
int err;
- if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM;
err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
--
2.18.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] kernel: initialize cpumask before parsing
2021-04-01 5:58 [PATCH] kernel: initialize cpumask before parsing Tetsuo Handa
@ 2021-04-01 13:34 ` Steven Rostedt
2021-04-10 11:38 ` [tip: irq/core] kernel: Initialize " tip-bot2 for Tetsuo Handa
1 sibling, 0 replies; 3+ messages in thread
From: Steven Rostedt @ 2021-04-01 13:34 UTC (permalink / raw)
To: Tetsuo Handa; +Cc: Thomas Gleixner, Ingo Molnar, linux-kernel
On Thu, 1 Apr 2021 14:58:23 +0900
Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> wrote:
> KMSAN complains that new_value at cpumask_parse_user() from
> write_irq_affinity() from irq_affinity_proc_write() is uninitialized.
>
> [ 148.133411][ T5509] =====================================================
> [ 148.135383][ T5509] BUG: KMSAN: uninit-value in find_next_bit+0x325/0x340
> [ 148.137819][ T5509]
> [ 148.138448][ T5509] Local variable ----new_value.i@irq_affinity_proc_write created at:
> [ 148.140768][ T5509] irq_affinity_proc_write+0xc3/0x3d0
> [ 148.142298][ T5509] irq_affinity_proc_write+0xc3/0x3d0
> [ 148.143823][ T5509] =====================================================
>
> Since bitmap_parse() from cpumask_parse_user() calls find_next_bit(),
> any alloc_cpumask_var() + cpumask_parse_user() sequence has possibility
> that find_next_bit() accesses uninitialized cpu mask variable. Fix this
> problem by replacing alloc_cpumask_var() with zalloc_cpumask_var().
>
> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> ---
> kernel/irq/proc.c | 4 ++--
> kernel/profile.c | 2 +-
> kernel/trace/trace.c | 2 +-
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-- Steve
^ permalink raw reply [flat|nested] 3+ messages in thread
* [tip: irq/core] kernel: Initialize cpumask before parsing
2021-04-01 5:58 [PATCH] kernel: initialize cpumask before parsing Tetsuo Handa
2021-04-01 13:34 ` Steven Rostedt
@ 2021-04-10 11:38 ` tip-bot2 for Tetsuo Handa
1 sibling, 0 replies; 3+ messages in thread
From: tip-bot2 for Tetsuo Handa @ 2021-04-10 11:38 UTC (permalink / raw)
To: linux-tip-commits
Cc: Tetsuo Handa, Thomas Gleixner, Steven Rostedt (VMware),
x86, linux-kernel, maz
The following commit has been merged into the irq/core branch of tip:
Commit-ID: c5e3a41187ac01425f5ad1abce927905e4ac44e4
Gitweb: https://git.kernel.org/tip/c5e3a41187ac01425f5ad1abce927905e4ac44e4
Author: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
AuthorDate: Thu, 01 Apr 2021 14:58:23 +09:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sat, 10 Apr 2021 13:35:54 +02:00
kernel: Initialize cpumask before parsing
KMSAN complains that new_value at cpumask_parse_user() from
write_irq_affinity() from irq_affinity_proc_write() is uninitialized.
[ 148.133411][ T5509] =====================================================
[ 148.135383][ T5509] BUG: KMSAN: uninit-value in find_next_bit+0x325/0x340
[ 148.137819][ T5509]
[ 148.138448][ T5509] Local variable ----new_value.i@irq_affinity_proc_write created at:
[ 148.140768][ T5509] irq_affinity_proc_write+0xc3/0x3d0
[ 148.142298][ T5509] irq_affinity_proc_write+0xc3/0x3d0
[ 148.143823][ T5509] =====================================================
Since bitmap_parse() from cpumask_parse_user() calls find_next_bit(),
any alloc_cpumask_var() + cpumask_parse_user() sequence has possibility
that find_next_bit() accesses uninitialized cpu mask variable. Fix this
problem by replacing alloc_cpumask_var() with zalloc_cpumask_var().
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20210401055823.3929-1-penguin-kernel@I-love.SAKURA.ne.jp
---
kernel/irq/proc.c | 4 ++--
kernel/profile.c | 2 +-
kernel/trace/trace.c | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 9813878..7c5cd42 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -144,7 +144,7 @@ static ssize_t write_irq_affinity(int type, struct file *file,
if (!irq_can_set_affinity_usr(irq) || no_irq_affinity)
return -EIO;
- if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&new_value, GFP_KERNEL))
return -ENOMEM;
if (type)
@@ -238,7 +238,7 @@ static ssize_t default_affinity_write(struct file *file,
cpumask_var_t new_value;
int err;
- if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&new_value, GFP_KERNEL))
return -ENOMEM;
err = cpumask_parse_user(buffer, count, new_value);
diff --git a/kernel/profile.c b/kernel/profile.c
index 6f69a41..c2ebddb 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -430,7 +430,7 @@ static ssize_t prof_cpu_mask_proc_write(struct file *file,
cpumask_var_t new_value;
int err;
- if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&new_value, GFP_KERNEL))
return -ENOMEM;
err = cpumask_parse_user(buffer, count, new_value);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index eccb4e1..7607dc8 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4827,7 +4827,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
cpumask_var_t tracing_cpumask_new;
int err;
- if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM;
err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
^ permalink raw reply related [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-04-10 11:38 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2021-04-01 5:58 [PATCH] kernel: initialize cpumask before parsing Tetsuo Handa
2021-04-01 13:34 ` Steven Rostedt
2021-04-10 11:38 ` [tip: irq/core] kernel: Initialize " tip-bot2 for Tetsuo Handa
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