Re: proc_dointvec() and write

From: Cong Wang
Date: Tue May 25 2010 - 00:46:02 EST


On 05/24/10 22:32, J. R. Okajima wrote:
The commit 00b7c3395aec3df43de5bd02a3c5a099ca51169f
"sysctl: refactor integer handling proc code"
modified the behaviour of writing to /proc.

Before the commit, write("1\n") to /proc/sys/kernel/printk succeeded. But
now it returns EINVAL. Is this intended change? If not, how about this
patch?



Hmm, odd, I tested other proc files, I see no problem.
I am wondering why /proc/sys/kernel/printk is special here.

I will be back later.


J. R. Okajima

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 4c93486..5058e12 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2262,6 +2272,8 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
if (write) {
left -= proc_skip_spaces(&kbuf);

+ if (!left)
+ break;
err = proc_get_long(&kbuf,&left,&lval,&neg,
proc_wspace_sep,
sizeof(proc_wspace_sep), NULL);
@@ -2288,7 +2306,7 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,

if (!write&& !first&& left&& !err)
err = proc_put_char(&buffer,&left, '\n');
- if (write&& !err)
+ if (write&& !err&& left)
left -= proc_skip_spaces(&kbuf);
free:
if (write) {


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/