The patch titled
Subject: x86-olpc-add-debugfs-interface-for-ec-commands v3
has been added to the -mm tree. Its filename is
x86-olpc-add-debugfs-interface-for-ec-commands-v3.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Daniel Drake <dsd@xxxxxxxxxx>
Subject: x86-olpc-add-debugfs-interface-for-ec-commands v3
v3: incorporate feedback from Ingo Molnar (thanks!): whitespace/cast
fixes, fix potential overflow when nonsense resp_bytes is passed from
userspace, add mutex to protect data and to protect against concurrent
read/write, give node name 'cmd' which is better than 'generic'
Signed-off-by: Daniel Drake <dsd@xxxxxxxxxx>
Signed-off-by: Paul Fox <pgf@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Andres Salomon <dilinger@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/ABI/testing/debugfs-olpc | 4 +-
arch/x86/platform/olpc/olpc.c | 35 +++++++++++++++--------
2 files changed, 25 insertions(+), 14 deletions(-)
diff -puN Documentation/ABI/testing/debugfs-olpc~x86-olpc-add-debugfs-interface-for-ec-commands-v3 Documentation/ABI/testing/debugfs-olpc
--- a/Documentation/ABI/testing/debugfs-olpc~x86-olpc-add-debugfs-interface-for-ec-commands-v3
+++ a/Documentation/ABI/testing/debugfs-olpc
@@ -1,6 +1,6 @@
-What: /sys/kernel/debug/olpc-ec/generic
+What: /sys/kernel/debug/olpc-ec/cmd
Date: Dec 2011
-KernelVersion: 3.3
+KernelVersion: 3.4
Contact: devel@xxxxxxxxxxxxxxxx
Description:
diff -puN arch/x86/platform/olpc/olpc.c~x86-olpc-add-debugfs-interface-for-ec-commands-v3 arch/x86/platform/olpc/olpc.c
--- a/arch/x86/platform/olpc/olpc.c~x86-olpc-add-debugfs-interface-for-ec-commands-v3
+++ a/arch/x86/platform/olpc/olpc.c
@@ -21,6 +21,7 @@
#include <linux/of.h>
#include <linux/syscore_ops.h>
#include <linux/debugfs.h>
+#include <linux/mutex.h>
#include <asm/geode.h>
#include <asm/setup.h>
@@ -35,7 +36,9 @@ static DEFINE_SPINLOCK(ec_lock);
/* debugfs interface to EC commands */
#define EC_MAX_CMD_ARGS (5 + 1) /* cmd byte + 5 args */
#define EC_MAX_CMD_REPLY (8)
+
static struct dentry *ec_debugfs_dir;
+static DEFINE_MUTEX(ec_debugfs_cmd_lock);
static unsigned char ec_debugfs_resp[EC_MAX_CMD_REPLY];
static unsigned int ec_debugfs_resp_bytes;
@@ -277,8 +280,8 @@ int olpc_ec_sci_query(u16 *sci_value)
}
EXPORT_SYMBOL_GPL(olpc_ec_sci_query);
-static ssize_t ec_gen_write(struct file *file, const char __user *buf,
- size_t size, loff_t *ppos)
+static ssize_t ec_debugfs_cmd_write(struct file *file, const char __user *buf,
+ size_t size, loff_t *ppos)
{
int i, m;
unsigned char ec_cmd[EC_MAX_CMD_ARGS];
@@ -286,6 +289,8 @@ static ssize_t ec_gen_write(struct file
char cmdbuf[64];
int ec_cmd_bytes;
+ mutex_lock(&ec_debugfs_cmd_lock);
+
size = simple_write_to_buffer(cmdbuf, sizeof(cmdbuf), ppos, buf, size);
m = sscanf(cmdbuf, "%x:%u %x %x %x %x %x", &ec_cmd_int[0],
@@ -293,9 +298,13 @@ static ssize_t ec_gen_write(struct file
&ec_cmd_int[1], &ec_cmd_int[2], &ec_cmd_int[3],
&ec_cmd_int[4], &ec_cmd_int[5]);
if (m < 2 || ec_debugfs_resp_bytes > EC_MAX_CMD_REPLY) {
+ /* reset to prevent overflow on read */
+ ec_debugfs_resp_bytes = 0;
+
printk(KERN_DEBUG "olpc-ec: bad ec cmd: "
"cmd:response-count [arg1 [arg2 ...]]\n");
- return -EINVAL;
+ size = -EINVAL;
+ goto out;
}
/* convert scanf'd ints to char */
@@ -308,9 +317,8 @@ static ssize_t ec_gen_write(struct file
ec_cmd[0], ec_cmd_bytes, ec_cmd[1], ec_cmd[2], ec_cmd[3],
ec_cmd[4], ec_cmd[5], ec_debugfs_resp_bytes);
- olpc_ec_cmd((unsigned char) ec_cmd[0],
- (ec_cmd_bytes == 0) ? NULL : &ec_cmd[1],
- ec_cmd_bytes, ec_debugfs_resp, ec_debugfs_resp_bytes);
+ olpc_ec_cmd(ec_cmd[0], (ec_cmd_bytes == 0) ? NULL : &ec_cmd[1],
+ ec_cmd_bytes, ec_debugfs_resp, ec_debugfs_resp_bytes);
printk(KERN_DEBUG "olpc-ec: response "
"%02x %02x %02x %02x %02x %02x %02x %02x (%d bytes expected)\n",
@@ -318,30 +326,33 @@ static ssize_t ec_gen_write(struct file
ec_debugfs_resp[3], ec_debugfs_resp[4], ec_debugfs_resp[5],
ec_debugfs_resp[6], ec_debugfs_resp[7], ec_debugfs_resp_bytes);
+out:
+ mutex_unlock(&ec_debugfs_cmd_lock);
return size;
}
-static ssize_t ec_gen_read(struct file *file, char __user *buf,
- size_t size, loff_t *ppos)
+static ssize_t ec_debugfs_cmd_read(struct file *file, char __user *buf,
+ size_t size, loff_t *ppos)
{
unsigned int i, r;
char *rp;
char respbuf[64];
+ mutex_lock(&ec_debugfs_cmd_lock);
rp = respbuf;
rp += sprintf(rp, "%02x", ec_debugfs_resp[0]);
for (i = 1; i < ec_debugfs_resp_bytes; i++)
rp += sprintf(rp, ", %02x", ec_debugfs_resp[i]);
+ mutex_unlock(&ec_debugfs_cmd_lock);
rp += sprintf(rp, "\n");
r = rp - respbuf;
-
return simple_read_from_buffer(buf, size, ppos, respbuf, r);
}
static const struct file_operations ec_debugfs_genops = {
- .write = ec_gen_write,
- .read = ec_gen_read,
+ .write = ec_debugfs_cmd_write,
+ .read = ec_debugfs_cmd_read,
};
static void setup_debugfs(void)
@@ -350,7 +361,7 @@ static void setup_debugfs(void)
if (ec_debugfs_dir == ERR_PTR(-ENODEV))
return;
- debugfs_create_file("generic", 0600, ec_debugfs_dir, NULL,
+ debugfs_create_file("cmd", 0600, ec_debugfs_dir, NULL,
&ec_debugfs_genops);
}
_
Subject: Subject: x86-olpc-add-debugfs-interface-for-ec-commands v3
Patches currently in -mm which might be from dsd@xxxxxxxxxx are
linux-next.patch
platform-drivers-x86-convert-drivers-platform-x86-to-use-module_platform_driver.patch
x86-olpc-add-debugfs-interface-for-ec-commands.patch
x86-olpc-add-debugfs-interface-for-ec-commands-v3.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
