kernel_optimize_test/net/sunrpc/sysctl.c
Christoph Hellwig 32927393dc sysctl: pass kernel pointers to ->proc_handler
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from  userspace in common code.  This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-27 02:07:40 -04:00

185 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/net/sunrpc/sysctl.c
*
* Sysctl interface to sunrpc module.
*
* I would prefer to register the sunrpc table below sys/net, but that's
* impossible at the moment.
*/
#include <linux/types.h>
#include <linux/linkage.h>
#include <linux/ctype.h>
#include <linux/fs.h>
#include <linux/sysctl.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/svc_xprt.h>
#include "netns.h"
/*
* Declare the debug flags here
*/
unsigned int rpc_debug;
EXPORT_SYMBOL_GPL(rpc_debug);
unsigned int nfs_debug;
EXPORT_SYMBOL_GPL(nfs_debug);
unsigned int nfsd_debug;
EXPORT_SYMBOL_GPL(nfsd_debug);
unsigned int nlm_debug;
EXPORT_SYMBOL_GPL(nlm_debug);
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
static struct ctl_table_header *sunrpc_table_header;
static struct ctl_table sunrpc_table[];
void
rpc_register_sysctl(void)
{
if (!sunrpc_table_header)
sunrpc_table_header = register_sysctl_table(sunrpc_table);
}
void
rpc_unregister_sysctl(void)
{
if (sunrpc_table_header) {
unregister_sysctl_table(sunrpc_table_header);
sunrpc_table_header = NULL;
}
}
static int proc_do_xprt(struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
char tmpbuf[256];
size_t len;
if ((*ppos && !write) || !*lenp) {
*lenp = 0;
return 0;
}
len = svc_print_xprts(tmpbuf, sizeof(tmpbuf));
return memory_read_from_buffer(buffer, *lenp, ppos, tmpbuf, len);
}
static int
proc_dodebug(struct ctl_table *table, int write, void *buffer, size_t *lenp,
loff_t *ppos)
{
char tmpbuf[20], *s = NULL;
char *p;
unsigned int value;
size_t left, len;
if ((*ppos && !write) || !*lenp) {
*lenp = 0;
return 0;
}
left = *lenp;
if (write) {
p = buffer;
while (left && isspace(*p)) {
left--;
p++;
}
if (!left)
goto done;
if (left > sizeof(tmpbuf) - 1)
return -EINVAL;
memcpy(tmpbuf, p, left);
tmpbuf[left] = '\0';
value = simple_strtol(tmpbuf, &s, 0);
if (s) {
left -= (s - tmpbuf);
if (left && !isspace(*s))
return -EINVAL;
while (left && isspace(*s))
left--, s++;
} else
left = 0;
*(unsigned int *) table->data = value;
/* Display the RPC tasks on writing to rpc_debug */
if (strcmp(table->procname, "rpc_debug") == 0)
rpc_show_tasks(&init_net);
} else {
len = sprintf(tmpbuf, "0x%04x", *(unsigned int *) table->data);
if (len > left)
len = left;
memcpy(buffer, tmpbuf, len);
if ((left -= len) > 0) {
*((char *)buffer + len) = '\n';
left--;
}
}
done:
*lenp -= left;
*ppos += *lenp;
return 0;
}
static struct ctl_table debug_table[] = {
{
.procname = "rpc_debug",
.data = &rpc_debug,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dodebug
},
{
.procname = "nfs_debug",
.data = &nfs_debug,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dodebug
},
{
.procname = "nfsd_debug",
.data = &nfsd_debug,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dodebug
},
{
.procname = "nlm_debug",
.data = &nlm_debug,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dodebug
},
{
.procname = "transports",
.maxlen = 256,
.mode = 0444,
.proc_handler = proc_do_xprt,
},
{ }
};
static struct ctl_table sunrpc_table[] = {
{
.procname = "sunrpc",
.mode = 0555,
.child = debug_table
},
{ }
};
#endif