tracing: Prevent bad count for tracing_cpumask_write

If a large count is provided, it will trigger a warning in bitmap_parse_user.
Also check zero for it.

Cc: stable@vger.kernel.org
Fixes: 9e01c1b74c ("cpumask: convert kernel trace functions")
Link: https://lore.kernel.org/20241216073238.2573704-1-lizhi.xu@windriver.com
Reported-by: syzbot+0aecfd34fb878546f3fd@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0aecfd34fb878546f3fd
Tested-by: syzbot+0aecfd34fb878546f3fd@syzkaller.appspotmail.com
Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Lizhi Xu
2024-12-16 15:32:38 +08:00
committed by Steven Rostedt (Google)
parent 452f4b31e3
commit 98feccbf32

View File

@@ -5087,6 +5087,9 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
cpumask_var_t tracing_cpumask_new;
int err;
if (count == 0 || count > KMALLOC_MAX_SIZE)
return -EINVAL;
if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM;