LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Yi Yang <yi.y.yang@intel.com>
To: linux-acpi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, lenb@kernel.org,
	acpi-bugzilla@lists.sourceforge.net
Subject: [PATCH linux-acpi] fix acpi fan state set error
Date: Fri, 04 Jan 2008 16:16:42 +0800	[thread overview]
Message-ID: <1199434602.19185.1.camel@yangyi-dev.bj.intel.com> (raw)
In-Reply-To: <1198916553.3806.2.camel@yangyi-dev.bj.intel.com>

Subject: ACPI: fix acpi fan state set error
From: Yi Yang <yi.y.yang@intel.com>

Under /proc/acpi, there is a fan control interface, a user can
set 0 or 3 to /proc/acpi/fan/*/state, 0 denotes D0 state, 3
denotes D3 state, but in current implementation, a user can
set a fan to D1 state by any char excluding '1', '2' and '3'.

For example:

[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost acpi]# echo "" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  on
[root@localhost acpi]# echo "3" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost acpi]# echo "xxxxx" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  on

Obviously, such inputs as "" and "xxxxx" are invalid for fan state.

This patch fixes this issue, it strictly limits fan state only to
accept 0, 1, 2 and 3, any other inputs are invalid.

Before applying this patch, the test result is:

[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost acpi]# echo "" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  on
[root@localhost acpi]# echo "3" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost acpi]# echo "xxxxx" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  on
[root@localhost acpi]# echo "3" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost acpi]# echo "3x" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost acpi]# echo "-1x" > /proc/acpi/fan/C31B/state
[root@localhost acpi]# cat /proc/acpi/fan/C31B/state
status:                  on
[root@localhost acpi]#


After applying this patch, the test result is:

[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost ~]# echo "" > /proc/acpi/fan/C31B/state
-bash: echo: write error: Invalid argument
[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost ~]# echo "3" > /proc/acpi/fan/C31B/state
[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost ~]# echo "xxxxx" > /proc/acpi/fan/C31B/state
-bash: echo: write error: Invalid argument
[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost ~]# echo "-1x" > /proc/acpi/fan/C31B/state
-bash: echo: write error: Invalid argument
[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost ~]# echo "0" > //proc/acpi/fan/C31B/state
[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  on
[root@localhost ~]# echo "4" > //proc/acpi/fan/C31B/state
-bash: echo: write error: Invalid argument
[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  on
[root@localhost ~]# echo "3" > //proc/acpi/fan/C31B/state
[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  off
[root@localhost ~]# echo "0" > //proc/acpi/fan/C31B/state
[root@localhost ~]# cat /proc/acpi/fan/C31B/state
status:                  on
[root@localhost ~]# echo "3x" > //proc/acpi/fan/C31B/state
-bash: echo: write error: Invalid argument
[root@localhost ~]#


Signed-off-by: Yi Yang <yi.y.yang@intel.com>
---
 fan.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/fan.c b/drivers/acpi/fan.c
index a5a5532..53f7c72 100644
--- a/drivers/acpi/fan.c
+++ b/drivers/acpi/fan.c
@@ -98,7 +98,7 @@ acpi_fan_write_state(struct file *file, const char __user * buffer,
 	int result = 0;
 	struct seq_file *m = file->private_data;
 	struct acpi_device *device = m->private;
-	char state_string[12] = { '\0' };
+	char state_string[3] = { '\0' };
 
 	if (count > sizeof(state_string) - 1)
 		return -EINVAL;
@@ -107,6 +107,12 @@ acpi_fan_write_state(struct file *file, const char __user * buffer,
 		return -EFAULT;
 
 	state_string[count] = '\0';
+	if ((state_string[0] < '0') || (state_string[0] > '3'))
+		return -EINVAL;
+	if (state_string[1] == '\n')
+		state_string[1] = '\0';
+	if (state_string[1] != '\0')
+		return -EINVAL;
 
 	result = acpi_bus_set_power(device->handle,
 				    simple_strtoul(state_string, NULL, 0));



  parent reply	other threads:[~2008-01-04  8:25 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-27  6:47 [PATCH linux-acpi] Fix /proc/acpi/alarm " Yi Yang
2007-12-27  8:41 ` [PATCH linux-acpi] Remove superfluous code and correct counting error in function acpi_system_write_alarm Yi Yang
2007-12-29  8:22   ` [PATCH linux-acpi] Correct wakeup set error and append a new column PCI ID Yi Yang
2008-01-01 23:20     ` Pavel Machek
2008-01-02  2:03       ` Yi Yang
2008-01-02 16:09         ` Pavel Machek
2008-01-03  2:02           ` Yi Yang
2008-01-03  2:11           ` Yi Yang
2008-01-04  8:16     ` Yi Yang [this message]
2008-01-07  6:56       ` [PATCH] ACPI: fix processor throttling set error Yi Yang
2008-01-08  3:21         ` [PATCH] ACPI: fix processor limit " Yi Yang
2008-01-24  0:45           ` [PATCH] ACPI: create proc entry 'power' only if C2 or C3 is supported Yi Yang
2008-01-24 14:43             ` Mark Lord
2008-01-09 22:21         ` [PATCH] ACPI: Add sysfs interface for acpi device wakeup Yi Yang
2008-01-10  7:43           ` Maxim Levitsky
2008-01-09 23:59             ` Yi Yang
2008-01-10 10:30               ` Matthew Garrett
2008-01-13 18:16               ` Pavel Machek
2008-01-11  8:16             ` Zhang Rui
2008-01-10 23:55               ` Yi Yang
2008-03-19 13:06                 ` Thomas Renninger
2008-03-19 14:37                   ` Yi Yang
2008-03-20  4:32                     ` Zhao Yakui
2008-03-19 18:52                   ` David Brownell
2008-03-20  5:12                     ` Zhao Yakui
2008-03-20  6:12                       ` David Brownell

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1199434602.19185.1.camel@yangyi-dev.bj.intel.com \
    --to=yi.y.yang@intel.com \
    --cc=acpi-bugzilla@lists.sourceforge.net \
    --cc=lenb@kernel.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --subject='Re: [PATCH linux-acpi] fix acpi fan state set error' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).