Revision 71aa60f67f032dffe58999bd8ae4b2f38a9ea05e authored by Linus Torvalds on 23 September 2017, 15:41:27 UTC, committed by Linus Torvalds on 23 September 2017, 15:41:27 UTC
Pull networking fixes from David Miller: 1) Fix NAPI poll list corruption in enic driver, from Christian Lamparter. 2) Fix route use after free, from Eric Dumazet. 3) Fix regression in reuseaddr handling, from Josef Bacik. 4) Assert the size of control messages in compat handling since we copy it in from userspace twice. From Meng Xu. 5) SMC layer bug fixes (missing RCU locking, bad refcounting, etc.) from Ursula Braun. 6) Fix races in AF_PACKET fanout handling, from Willem de Bruijn. 7) Don't use ARRAY_SIZE on spinlock array which might have zero entries, from Geert Uytterhoeven. 8) Fix miscomputation of checksum in ipv6 udp code, from Subash Abhinov Kasiviswanathan. 9) Push the ipv6 header properly in ipv6 GRE tunnel driver, from Xin Long. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (75 commits) inet: fix improper empty comparison net: use inet6_rcv_saddr to compare sockets net: set tb->fast_sk_family net: orphan frags on stand-alone ptype in dev_queue_xmit_nit MAINTAINERS: update git tree locations for ieee802154 subsystem net: prevent dst uses after free net: phy: Fix truncation of large IRQ numbers in phy_attached_print() net/smc: no close wait in case of process shut down net/smc: introduce a delay net/smc: terminate link group if out-of-sync is received net/smc: longer delay for client link group removal net/smc: adapt send request completion notification net/smc: adjust net_device refcount net/smc: take RCU read lock for routing cache lookup net/smc: add receive timeout check net/smc: add missing dev_put net: stmmac: Cocci spatch "of_table" lan78xx: Use default values loaded from EEPROM/OTP after reset lan78xx: Allow EEPROM write for less than MAX_EEPROM_SIZE lan78xx: Fix for eeprom read/write when device auto suspend ...
dcookies.c
/*
* dcookies.c
*
* Copyright 2002 John Levon <levon@movementarian.org>
*
* Persistent cookie-path mappings. These are used by
* profilers to convert a per-task EIP value into something
* non-transitory that can be processed at a later date.
* This is done by locking the dentry/vfsmnt pair in the
* kernel until released by the tasks needing the persistent
* objects. The tag is simply an unsigned long that refers
* to the pair and can be looked up from userspace.
*/
#include <linux/syscalls.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/mount.h>
#include <linux/capability.h>
#include <linux/dcache.h>
#include <linux/mm.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/dcookies.h>
#include <linux/mutex.h>
#include <linux/path.h>
#include <linux/compat.h>
#include <linux/uaccess.h>
/* The dcookies are allocated from a kmem_cache and
* hashed onto a small number of lists. None of the
* code here is particularly performance critical
*/
struct dcookie_struct {
struct path path;
struct list_head hash_list;
};
static LIST_HEAD(dcookie_users);
static DEFINE_MUTEX(dcookie_mutex);
static struct kmem_cache *dcookie_cache __read_mostly;
static struct list_head *dcookie_hashtable __read_mostly;
static size_t hash_size __read_mostly;
static inline int is_live(void)
{
return !(list_empty(&dcookie_users));
}
/* The dentry is locked, its address will do for the cookie */
static inline unsigned long dcookie_value(struct dcookie_struct * dcs)
{
return (unsigned long)dcs->path.dentry;
}
static size_t dcookie_hash(unsigned long dcookie)
{
return (dcookie >> L1_CACHE_SHIFT) & (hash_size - 1);
}
static struct dcookie_struct * find_dcookie(unsigned long dcookie)
{
struct dcookie_struct *found = NULL;
struct dcookie_struct * dcs;
struct list_head * pos;
struct list_head * list;
list = dcookie_hashtable + dcookie_hash(dcookie);
list_for_each(pos, list) {
dcs = list_entry(pos, struct dcookie_struct, hash_list);
if (dcookie_value(dcs) == dcookie) {
found = dcs;
break;
}
}
return found;
}
static void hash_dcookie(struct dcookie_struct * dcs)
{
struct list_head * list = dcookie_hashtable + dcookie_hash(dcookie_value(dcs));
list_add(&dcs->hash_list, list);
}
static struct dcookie_struct *alloc_dcookie(const struct path *path)
{
struct dcookie_struct *dcs = kmem_cache_alloc(dcookie_cache,
GFP_KERNEL);
struct dentry *d;
if (!dcs)
return NULL;
d = path->dentry;
spin_lock(&d->d_lock);
d->d_flags |= DCACHE_COOKIE;
spin_unlock(&d->d_lock);
dcs->path = *path;
path_get(path);
hash_dcookie(dcs);
return dcs;
}
/* This is the main kernel-side routine that retrieves the cookie
* value for a dentry/vfsmnt pair.
*/
int get_dcookie(const struct path *path, unsigned long *cookie)
{
int err = 0;
struct dcookie_struct * dcs;
mutex_lock(&dcookie_mutex);
if (!is_live()) {
err = -EINVAL;
goto out;
}
if (path->dentry->d_flags & DCACHE_COOKIE) {
dcs = find_dcookie((unsigned long)path->dentry);
} else {
dcs = alloc_dcookie(path);
if (!dcs) {
err = -ENOMEM;
goto out;
}
}
*cookie = dcookie_value(dcs);
out:
mutex_unlock(&dcookie_mutex);
return err;
}
/* And here is where the userspace process can look up the cookie value
* to retrieve the path.
*/
SYSCALL_DEFINE3(lookup_dcookie, u64, cookie64, char __user *, buf, size_t, len)
{
unsigned long cookie = (unsigned long)cookie64;
int err = -EINVAL;
char * kbuf;
char * path;
size_t pathlen;
struct dcookie_struct * dcs;
/* we could leak path information to users
* without dir read permission without this
*/
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
mutex_lock(&dcookie_mutex);
if (!is_live()) {
err = -EINVAL;
goto out;
}
if (!(dcs = find_dcookie(cookie)))
goto out;
err = -ENOMEM;
kbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!kbuf)
goto out;
/* FIXME: (deleted) ? */
path = d_path(&dcs->path, kbuf, PAGE_SIZE);
mutex_unlock(&dcookie_mutex);
if (IS_ERR(path)) {
err = PTR_ERR(path);
goto out_free;
}
err = -ERANGE;
pathlen = kbuf + PAGE_SIZE - path;
if (pathlen <= len) {
err = pathlen;
if (copy_to_user(buf, path, pathlen))
err = -EFAULT;
}
out_free:
kfree(kbuf);
return err;
out:
mutex_unlock(&dcookie_mutex);
return err;
}
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE4(lookup_dcookie, u32, w0, u32, w1, char __user *, buf, compat_size_t, len)
{
#ifdef __BIG_ENDIAN
return sys_lookup_dcookie(((u64)w0 << 32) | w1, buf, len);
#else
return sys_lookup_dcookie(((u64)w1 << 32) | w0, buf, len);
#endif
}
#endif
static int dcookie_init(void)
{
struct list_head * d;
unsigned int i, hash_bits;
int err = -ENOMEM;
dcookie_cache = kmem_cache_create("dcookie_cache",
sizeof(struct dcookie_struct),
0, 0, NULL);
if (!dcookie_cache)
goto out;
dcookie_hashtable = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!dcookie_hashtable)
goto out_kmem;
err = 0;
/*
* Find the power-of-two list-heads that can fit into the allocation..
* We don't guarantee that "sizeof(struct list_head)" is necessarily
* a power-of-two.
*/
hash_size = PAGE_SIZE / sizeof(struct list_head);
hash_bits = 0;
do {
hash_bits++;
} while ((hash_size >> hash_bits) != 0);
hash_bits--;
/*
* Re-calculate the actual number of entries and the mask
* from the number of bits we can fit.
*/
hash_size = 1UL << hash_bits;
/* And initialize the newly allocated array */
d = dcookie_hashtable;
i = hash_size;
do {
INIT_LIST_HEAD(d);
d++;
i--;
} while (i);
out:
return err;
out_kmem:
kmem_cache_destroy(dcookie_cache);
goto out;
}
static void free_dcookie(struct dcookie_struct * dcs)
{
struct dentry *d = dcs->path.dentry;
spin_lock(&d->d_lock);
d->d_flags &= ~DCACHE_COOKIE;
spin_unlock(&d->d_lock);
path_put(&dcs->path);
kmem_cache_free(dcookie_cache, dcs);
}
static void dcookie_exit(void)
{
struct list_head * list;
struct list_head * pos;
struct list_head * pos2;
struct dcookie_struct * dcs;
size_t i;
for (i = 0; i < hash_size; ++i) {
list = dcookie_hashtable + i;
list_for_each_safe(pos, pos2, list) {
dcs = list_entry(pos, struct dcookie_struct, hash_list);
list_del(&dcs->hash_list);
free_dcookie(dcs);
}
}
kfree(dcookie_hashtable);
kmem_cache_destroy(dcookie_cache);
}
struct dcookie_user {
struct list_head next;
};
struct dcookie_user * dcookie_register(void)
{
struct dcookie_user * user;
mutex_lock(&dcookie_mutex);
user = kmalloc(sizeof(struct dcookie_user), GFP_KERNEL);
if (!user)
goto out;
if (!is_live() && dcookie_init())
goto out_free;
list_add(&user->next, &dcookie_users);
out:
mutex_unlock(&dcookie_mutex);
return user;
out_free:
kfree(user);
user = NULL;
goto out;
}
void dcookie_unregister(struct dcookie_user * user)
{
mutex_lock(&dcookie_mutex);
list_del(&user->next);
kfree(user);
if (!is_live())
dcookie_exit();
mutex_unlock(&dcookie_mutex);
}
EXPORT_SYMBOL_GPL(dcookie_register);
EXPORT_SYMBOL_GPL(dcookie_unregister);
EXPORT_SYMBOL_GPL(get_dcookie);
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