Revision b85bfa246efd24ea3fdb5ee949c28e3110c6d299 authored by Daniel Kurtz on 22 September 2018, 19:58:26 UTC, committed by Linus Walleij on 25 September 2018, 10:39:19 UTC
From the AMD BKDG, if WAKE_INT_MASTER_REG.MaskStsEn is set, a software write to the debounce registers of *any* gpio will block wake/interrupt status generation for *all* gpios for a length of time that depends on WAKE_INT_MASTER_REG.MaskStsLength[11:0]. During this period the Interrupt Delivery bit (INTERRUPT_ENABLE) will read as 0. In commit 4c1de0414a1340 ("pinctrl/amd: poll InterruptEnable bits in enable_irq") we tried to fix this same "gpio Interrupts are blocked immediately after writing debounce registers" problem, but incorrectly assumed it only affected the gpio whose debounce was being configured and not ALL gpios. To solve this for all gpios, we move the polling loop from amd_gpio_irq_enable() to amd_gpio_irq_set_type(), while holding the gpio spinlock. This ensures that another gpio operation (e.g. amd_gpio_irq_unmask()) can read a temporarily disabled IRQ and incorrectly disable it while trying to modify some other register bits. Fixes: 4c1de0414a1340 pinctrl/amd: poll InterruptEnable bits in enable_irq Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
1 parent 6bf4ca7
dns_key.c
/* Key type used to cache DNS lookups made by the kernel
*
* See Documentation/networking/dns_resolver.txt
*
* Copyright (c) 2007 Igor Mammedov
* Author(s): Igor Mammedov (niallain@gmail.com)
* Steve French (sfrench@us.ibm.com)
* Wang Lei (wang840925@gmail.com)
* David Howells (dhowells@redhat.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/keyctl.h>
#include <linux/err.h>
#include <linux/seq_file.h>
#include <keys/dns_resolver-type.h>
#include <keys/user-type.h>
#include "internal.h"
MODULE_DESCRIPTION("DNS Resolver");
MODULE_AUTHOR("Wang Lei");
MODULE_LICENSE("GPL");
unsigned int dns_resolver_debug;
module_param_named(debug, dns_resolver_debug, uint, 0644);
MODULE_PARM_DESC(debug, "DNS Resolver debugging mask");
const struct cred *dns_resolver_cache;
#define DNS_ERRORNO_OPTION "dnserror"
/*
* Preparse instantiation data for a dns_resolver key.
*
* The data must be a NUL-terminated string, with the NUL char accounted in
* datalen.
*
* If the data contains a '#' characters, then we take the clause after each
* one to be an option of the form 'key=value'. The actual data of interest is
* the string leading up to the first '#'. For instance:
*
* "ip1,ip2,...#foo=bar"
*/
static int
dns_resolver_preparse(struct key_preparsed_payload *prep)
{
struct user_key_payload *upayload;
unsigned long derrno;
int ret;
int datalen = prep->datalen, result_len = 0;
const char *data = prep->data, *end, *opt;
kenter("'%*.*s',%u", datalen, datalen, data, datalen);
if (datalen <= 1 || !data || data[datalen - 1] != '\0')
return -EINVAL;
datalen--;
/* deal with any options embedded in the data */
end = data + datalen;
opt = memchr(data, '#', datalen);
if (!opt) {
/* no options: the entire data is the result */
kdebug("no options");
result_len = datalen;
} else {
const char *next_opt;
result_len = opt - data;
opt++;
kdebug("options: '%s'", opt);
do {
int opt_len, opt_nlen;
const char *eq;
char optval[128];
next_opt = memchr(opt, '#', end - opt) ?: end;
opt_len = next_opt - opt;
if (opt_len <= 0 || opt_len > sizeof(optval)) {
pr_warn_ratelimited("Invalid option length (%d) for dns_resolver key\n",
opt_len);
return -EINVAL;
}
eq = memchr(opt, '=', opt_len);
if (eq) {
opt_nlen = eq - opt;
eq++;
memcpy(optval, eq, next_opt - eq);
optval[next_opt - eq] = '\0';
} else {
opt_nlen = opt_len;
optval[0] = '\0';
}
kdebug("option '%*.*s' val '%s'",
opt_nlen, opt_nlen, opt, optval);
/* see if it's an error number representing a DNS error
* that's to be recorded as the result in this key */
if (opt_nlen == sizeof(DNS_ERRORNO_OPTION) - 1 &&
memcmp(opt, DNS_ERRORNO_OPTION, opt_nlen) == 0) {
kdebug("dns error number option");
ret = kstrtoul(optval, 10, &derrno);
if (ret < 0)
goto bad_option_value;
if (derrno < 1 || derrno > 511)
goto bad_option_value;
kdebug("dns error no. = %lu", derrno);
prep->payload.data[dns_key_error] = ERR_PTR(-derrno);
continue;
}
bad_option_value:
pr_warn_ratelimited("Option '%*.*s' to dns_resolver key: bad/missing value\n",
opt_nlen, opt_nlen, opt);
return -EINVAL;
} while (opt = next_opt + 1, opt < end);
}
/* don't cache the result if we're caching an error saying there's no
* result */
if (prep->payload.data[dns_key_error]) {
kleave(" = 0 [h_error %ld]", PTR_ERR(prep->payload.data[dns_key_error]));
return 0;
}
kdebug("store result");
prep->quotalen = result_len;
upayload = kmalloc(sizeof(*upayload) + result_len + 1, GFP_KERNEL);
if (!upayload) {
kleave(" = -ENOMEM");
return -ENOMEM;
}
upayload->datalen = result_len;
memcpy(upayload->data, data, result_len);
upayload->data[result_len] = '\0';
prep->payload.data[dns_key_data] = upayload;
kleave(" = 0");
return 0;
}
/*
* Clean up the preparse data
*/
static void dns_resolver_free_preparse(struct key_preparsed_payload *prep)
{
pr_devel("==>%s()\n", __func__);
kfree(prep->payload.data[dns_key_data]);
}
/*
* The description is of the form "[<type>:]<domain_name>"
*
* The domain name may be a simple name or an absolute domain name (which
* should end with a period). The domain name is case-independent.
*/
static bool dns_resolver_cmp(const struct key *key,
const struct key_match_data *match_data)
{
int slen, dlen, ret = 0;
const char *src = key->description, *dsp = match_data->raw_data;
kenter("%s,%s", src, dsp);
if (!src || !dsp)
goto no_match;
if (strcasecmp(src, dsp) == 0)
goto matched;
slen = strlen(src);
dlen = strlen(dsp);
if (slen <= 0 || dlen <= 0)
goto no_match;
if (src[slen - 1] == '.')
slen--;
if (dsp[dlen - 1] == '.')
dlen--;
if (slen != dlen || strncasecmp(src, dsp, slen) != 0)
goto no_match;
matched:
ret = 1;
no_match:
kleave(" = %d", ret);
return ret;
}
/*
* Preparse the match criterion.
*/
static int dns_resolver_match_preparse(struct key_match_data *match_data)
{
match_data->lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE;
match_data->cmp = dns_resolver_cmp;
return 0;
}
/*
* Describe a DNS key
*/
static void dns_resolver_describe(const struct key *key, struct seq_file *m)
{
seq_puts(m, key->description);
if (key_is_positive(key)) {
int err = PTR_ERR(key->payload.data[dns_key_error]);
if (err)
seq_printf(m, ": %d", err);
else
seq_printf(m, ": %u", key->datalen);
}
}
/*
* read the DNS data
* - the key's semaphore is read-locked
*/
static long dns_resolver_read(const struct key *key,
char __user *buffer, size_t buflen)
{
int err = PTR_ERR(key->payload.data[dns_key_error]);
if (err)
return err;
return user_read(key, buffer, buflen);
}
struct key_type key_type_dns_resolver = {
.name = "dns_resolver",
.preparse = dns_resolver_preparse,
.free_preparse = dns_resolver_free_preparse,
.instantiate = generic_key_instantiate,
.match_preparse = dns_resolver_match_preparse,
.revoke = user_revoke,
.destroy = user_destroy,
.describe = dns_resolver_describe,
.read = dns_resolver_read,
};
static int __init init_dns_resolver(void)
{
struct cred *cred;
struct key *keyring;
int ret;
/* create an override credential set with a special thread keyring in
* which DNS requests are cached
*
* this is used to prevent malicious redirections from being installed
* with add_key().
*/
cred = prepare_kernel_cred(NULL);
if (!cred)
return -ENOMEM;
keyring = keyring_alloc(".dns_resolver",
GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
(KEY_POS_ALL & ~KEY_POS_SETATTR) |
KEY_USR_VIEW | KEY_USR_READ,
KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto failed_put_cred;
}
ret = register_key_type(&key_type_dns_resolver);
if (ret < 0)
goto failed_put_key;
/* instruct request_key() to use this special keyring as a cache for
* the results it looks up */
set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
cred->thread_keyring = keyring;
cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
dns_resolver_cache = cred;
kdebug("DNS resolver keyring: %d\n", key_serial(keyring));
return 0;
failed_put_key:
key_put(keyring);
failed_put_cred:
put_cred(cred);
return ret;
}
static void __exit exit_dns_resolver(void)
{
key_revoke(dns_resolver_cache->thread_keyring);
unregister_key_type(&key_type_dns_resolver);
put_cred(dns_resolver_cache);
}
module_init(init_dns_resolver)
module_exit(exit_dns_resolver)
MODULE_LICENSE("GPL");
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