linux_dsm_epyc7002/net/core/skmsg.c
John Fastabend 95fa145479 bpf: sockmap/tls, close can race with map free
When a map free is called and in parallel a socket is closed we
have two paths that can potentially reset the socket prot ops, the
bpf close() path and the map free path. This creates a problem
with which prot ops should be used from the socket closed side.

If the map_free side completes first then we want to call the
original lowest level ops. However, if the tls path runs first
we want to call the sockmap ops. Additionally there was no locking
around prot updates in TLS code paths so the prot ops could
be changed multiple times once from TLS path and again from sockmap
side potentially leaving ops pointed at either TLS or sockmap
when psock and/or tls context have already been destroyed.

To fix this race first only update ops inside callback lock
so that TLS, sockmap and lowest level all agree on prot state.
Second and a ULP callback update() so that lower layers can
inform the upper layer when they are being removed allowing the
upper layer to reset prot ops.

This gets us close to allowing sockmap and tls to be stacked
in arbitrary order but will save that patch for *next trees.

v4:
 - make sure we don't free things for device;
 - remove the checks which swap the callbacks back
   only if TLS is at the top.

Reported-by: syzbot+06537213db7ba2745c4a@syzkaller.appspotmail.com
Fixes: 02c558b2d5 ("bpf: sockmap, support for msg_peek in sk_msg with redirect ingress")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-22 16:04:17 +02:00

835 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */
#include <linux/skmsg.h>
#include <linux/skbuff.h>
#include <linux/scatterlist.h>
#include <net/sock.h>
#include <net/tcp.h>
static bool sk_msg_try_coalesce_ok(struct sk_msg *msg, int elem_first_coalesce)
{
if (msg->sg.end > msg->sg.start &&
elem_first_coalesce < msg->sg.end)
return true;
if (msg->sg.end < msg->sg.start &&
(elem_first_coalesce > msg->sg.start ||
elem_first_coalesce < msg->sg.end))
return true;
return false;
}
int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,
int elem_first_coalesce)
{
struct page_frag *pfrag = sk_page_frag(sk);
int ret = 0;
len -= msg->sg.size;
while (len > 0) {
struct scatterlist *sge;
u32 orig_offset;
int use, i;
if (!sk_page_frag_refill(sk, pfrag))
return -ENOMEM;
orig_offset = pfrag->offset;
use = min_t(int, len, pfrag->size - orig_offset);
if (!sk_wmem_schedule(sk, use))
return -ENOMEM;
i = msg->sg.end;
sk_msg_iter_var_prev(i);
sge = &msg->sg.data[i];
if (sk_msg_try_coalesce_ok(msg, elem_first_coalesce) &&
sg_page(sge) == pfrag->page &&
sge->offset + sge->length == orig_offset) {
sge->length += use;
} else {
if (sk_msg_full(msg)) {
ret = -ENOSPC;
break;
}
sge = &msg->sg.data[msg->sg.end];
sg_unmark_end(sge);
sg_set_page(sge, pfrag->page, use, orig_offset);
get_page(pfrag->page);
sk_msg_iter_next(msg, end);
}
sk_mem_charge(sk, use);
msg->sg.size += use;
pfrag->offset += use;
len -= use;
}
return ret;
}
EXPORT_SYMBOL_GPL(sk_msg_alloc);
int sk_msg_clone(struct sock *sk, struct sk_msg *dst, struct sk_msg *src,
u32 off, u32 len)
{
int i = src->sg.start;
struct scatterlist *sge = sk_msg_elem(src, i);
struct scatterlist *sgd = NULL;
u32 sge_len, sge_off;
while (off) {
if (sge->length > off)
break;
off -= sge->length;
sk_msg_iter_var_next(i);
if (i == src->sg.end && off)
return -ENOSPC;
sge = sk_msg_elem(src, i);
}
while (len) {
sge_len = sge->length - off;
if (sge_len > len)
sge_len = len;
if (dst->sg.end)
sgd = sk_msg_elem(dst, dst->sg.end - 1);
if (sgd &&
(sg_page(sge) == sg_page(sgd)) &&
(sg_virt(sge) + off == sg_virt(sgd) + sgd->length)) {
sgd->length += sge_len;
dst->sg.size += sge_len;
} else if (!sk_msg_full(dst)) {
sge_off = sge->offset + off;
sk_msg_page_add(dst, sg_page(sge), sge_len, sge_off);
} else {
return -ENOSPC;
}
off = 0;
len -= sge_len;
sk_mem_charge(sk, sge_len);
sk_msg_iter_var_next(i);
if (i == src->sg.end && len)
return -ENOSPC;
sge = sk_msg_elem(src, i);
}
return 0;
}
EXPORT_SYMBOL_GPL(sk_msg_clone);
void sk_msg_return_zero(struct sock *sk, struct sk_msg *msg, int bytes)
{
int i = msg->sg.start;
do {
struct scatterlist *sge = sk_msg_elem(msg, i);
if (bytes < sge->length) {
sge->length -= bytes;
sge->offset += bytes;
sk_mem_uncharge(sk, bytes);
break;
}
sk_mem_uncharge(sk, sge->length);
bytes -= sge->length;
sge->length = 0;
sge->offset = 0;
sk_msg_iter_var_next(i);
} while (bytes && i != msg->sg.end);
msg->sg.start = i;
}
EXPORT_SYMBOL_GPL(sk_msg_return_zero);
void sk_msg_return(struct sock *sk, struct sk_msg *msg, int bytes)
{
int i = msg->sg.start;
do {
struct scatterlist *sge = &msg->sg.data[i];
int uncharge = (bytes < sge->length) ? bytes : sge->length;
sk_mem_uncharge(sk, uncharge);
bytes -= uncharge;
sk_msg_iter_var_next(i);
} while (i != msg->sg.end);
}
EXPORT_SYMBOL_GPL(sk_msg_return);
static int sk_msg_free_elem(struct sock *sk, struct sk_msg *msg, u32 i,
bool charge)
{
struct scatterlist *sge = sk_msg_elem(msg, i);
u32 len = sge->length;
if (charge)
sk_mem_uncharge(sk, len);
if (!msg->skb)
put_page(sg_page(sge));
memset(sge, 0, sizeof(*sge));
return len;
}
static int __sk_msg_free(struct sock *sk, struct sk_msg *msg, u32 i,
bool charge)
{
struct scatterlist *sge = sk_msg_elem(msg, i);
int freed = 0;
while (msg->sg.size) {
msg->sg.size -= sge->length;
freed += sk_msg_free_elem(sk, msg, i, charge);
sk_msg_iter_var_next(i);
sk_msg_check_to_free(msg, i, msg->sg.size);
sge = sk_msg_elem(msg, i);
}
if (msg->skb)
consume_skb(msg->skb);
sk_msg_init(msg);
return freed;
}
int sk_msg_free_nocharge(struct sock *sk, struct sk_msg *msg)
{
return __sk_msg_free(sk, msg, msg->sg.start, false);
}
EXPORT_SYMBOL_GPL(sk_msg_free_nocharge);
int sk_msg_free(struct sock *sk, struct sk_msg *msg)
{
return __sk_msg_free(sk, msg, msg->sg.start, true);
}
EXPORT_SYMBOL_GPL(sk_msg_free);
static void __sk_msg_free_partial(struct sock *sk, struct sk_msg *msg,
u32 bytes, bool charge)
{
struct scatterlist *sge;
u32 i = msg->sg.start;
while (bytes) {
sge = sk_msg_elem(msg, i);
if (!sge->length)
break;
if (bytes < sge->length) {
if (charge)
sk_mem_uncharge(sk, bytes);
sge->length -= bytes;
sge->offset += bytes;
msg->sg.size -= bytes;
break;
}
msg->sg.size -= sge->length;
bytes -= sge->length;
sk_msg_free_elem(sk, msg, i, charge);
sk_msg_iter_var_next(i);
sk_msg_check_to_free(msg, i, bytes);
}
msg->sg.start = i;
}
void sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, u32 bytes)
{
__sk_msg_free_partial(sk, msg, bytes, true);
}
EXPORT_SYMBOL_GPL(sk_msg_free_partial);
void sk_msg_free_partial_nocharge(struct sock *sk, struct sk_msg *msg,
u32 bytes)
{
__sk_msg_free_partial(sk, msg, bytes, false);
}
void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len)
{
int trim = msg->sg.size - len;
u32 i = msg->sg.end;
if (trim <= 0) {
WARN_ON(trim < 0);
return;
}
sk_msg_iter_var_prev(i);
msg->sg.size = len;
while (msg->sg.data[i].length &&
trim >= msg->sg.data[i].length) {
trim -= msg->sg.data[i].length;
sk_msg_free_elem(sk, msg, i, true);
sk_msg_iter_var_prev(i);
if (!trim)
goto out;
}
msg->sg.data[i].length -= trim;
sk_mem_uncharge(sk, trim);
out:
/* If we trim data before curr pointer update copybreak and current
* so that any future copy operations start at new copy location.
* However trimed data that has not yet been used in a copy op
* does not require an update.
*/
if (msg->sg.curr >= i) {
msg->sg.curr = i;
msg->sg.copybreak = msg->sg.data[i].length;
}
sk_msg_iter_var_next(i);
msg->sg.end = i;
}
EXPORT_SYMBOL_GPL(sk_msg_trim);
int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
struct sk_msg *msg, u32 bytes)
{
int i, maxpages, ret = 0, num_elems = sk_msg_elem_used(msg);
const int to_max_pages = MAX_MSG_FRAGS;
struct page *pages[MAX_MSG_FRAGS];
ssize_t orig, copied, use, offset;
orig = msg->sg.size;
while (bytes > 0) {
i = 0;
maxpages = to_max_pages - num_elems;
if (maxpages == 0) {
ret = -EFAULT;
goto out;
}
copied = iov_iter_get_pages(from, pages, bytes, maxpages,
&offset);
if (copied <= 0) {
ret = -EFAULT;
goto out;
}
iov_iter_advance(from, copied);
bytes -= copied;
msg->sg.size += copied;
while (copied) {
use = min_t(int, copied, PAGE_SIZE - offset);
sg_set_page(&msg->sg.data[msg->sg.end],
pages[i], use, offset);
sg_unmark_end(&msg->sg.data[msg->sg.end]);
sk_mem_charge(sk, use);
offset = 0;
copied -= use;
sk_msg_iter_next(msg, end);
num_elems++;
i++;
}
/* When zerocopy is mixed with sk_msg_*copy* operations we
* may have a copybreak set in this case clear and prefer
* zerocopy remainder when possible.
*/
msg->sg.copybreak = 0;
msg->sg.curr = msg->sg.end;
}
out:
/* Revert iov_iter updates, msg will need to use 'trim' later if it
* also needs to be cleared.
*/
if (ret)
iov_iter_revert(from, msg->sg.size - orig);
return ret;
}
EXPORT_SYMBOL_GPL(sk_msg_zerocopy_from_iter);
int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
struct sk_msg *msg, u32 bytes)
{
int ret = -ENOSPC, i = msg->sg.curr;
struct scatterlist *sge;
u32 copy, buf_size;
void *to;
do {
sge = sk_msg_elem(msg, i);
/* This is possible if a trim operation shrunk the buffer */
if (msg->sg.copybreak >= sge->length) {
msg->sg.copybreak = 0;
sk_msg_iter_var_next(i);
if (i == msg->sg.end)
break;
sge = sk_msg_elem(msg, i);
}
buf_size = sge->length - msg->sg.copybreak;
copy = (buf_size > bytes) ? bytes : buf_size;
to = sg_virt(sge) + msg->sg.copybreak;
msg->sg.copybreak += copy;
if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY)
ret = copy_from_iter_nocache(to, copy, from);
else
ret = copy_from_iter(to, copy, from);
if (ret != copy) {
ret = -EFAULT;
goto out;
}
bytes -= copy;
if (!bytes)
break;
msg->sg.copybreak = 0;
sk_msg_iter_var_next(i);
} while (i != msg->sg.end);
out:
msg->sg.curr = i;
return ret;
}
EXPORT_SYMBOL_GPL(sk_msg_memcopy_from_iter);
static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb)
{
struct sock *sk = psock->sk;
int copied = 0, num_sge;
struct sk_msg *msg;
msg = kzalloc(sizeof(*msg), __GFP_NOWARN | GFP_ATOMIC);
if (unlikely(!msg))
return -EAGAIN;
if (!sk_rmem_schedule(sk, skb, skb->len)) {
kfree(msg);
return -EAGAIN;
}
sk_msg_init(msg);
num_sge = skb_to_sgvec(skb, msg->sg.data, 0, skb->len);
if (unlikely(num_sge < 0)) {
kfree(msg);
return num_sge;
}
sk_mem_charge(sk, skb->len);
copied = skb->len;
msg->sg.start = 0;
msg->sg.size = copied;
msg->sg.end = num_sge == MAX_MSG_FRAGS ? 0 : num_sge;
msg->skb = skb;
sk_psock_queue_msg(psock, msg);
sk_psock_data_ready(sk, psock);
return copied;
}
static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb,
u32 off, u32 len, bool ingress)
{
if (ingress)
return sk_psock_skb_ingress(psock, skb);
else
return skb_send_sock_locked(psock->sk, skb, off, len);
}
static void sk_psock_backlog(struct work_struct *work)
{
struct sk_psock *psock = container_of(work, struct sk_psock, work);
struct sk_psock_work_state *state = &psock->work_state;
struct sk_buff *skb;
bool ingress;
u32 len, off;
int ret;
/* Lock sock to avoid losing sk_socket during loop. */
lock_sock(psock->sk);
if (state->skb) {
skb = state->skb;
len = state->len;
off = state->off;
state->skb = NULL;
goto start;
}
while ((skb = skb_dequeue(&psock->ingress_skb))) {
len = skb->len;
off = 0;
start:
ingress = tcp_skb_bpf_ingress(skb);
do {
ret = -EIO;
if (likely(psock->sk->sk_socket))
ret = sk_psock_handle_skb(psock, skb, off,
len, ingress);
if (ret <= 0) {
if (ret == -EAGAIN) {
state->skb = skb;
state->len = len;
state->off = off;
goto end;
}
/* Hard errors break pipe and stop xmit. */
sk_psock_report_error(psock, ret ? -ret : EPIPE);
sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED);
kfree_skb(skb);
goto end;
}
off += ret;
len -= ret;
} while (len);
if (!ingress)
kfree_skb(skb);
}
end:
release_sock(psock->sk);
}
struct sk_psock *sk_psock_init(struct sock *sk, int node)
{
struct sk_psock *psock = kzalloc_node(sizeof(*psock),
GFP_ATOMIC | __GFP_NOWARN,
node);
if (!psock)
return NULL;
psock->sk = sk;
psock->eval = __SK_NONE;
INIT_LIST_HEAD(&psock->link);
spin_lock_init(&psock->link_lock);
INIT_WORK(&psock->work, sk_psock_backlog);
INIT_LIST_HEAD(&psock->ingress_msg);
skb_queue_head_init(&psock->ingress_skb);
sk_psock_set_state(psock, SK_PSOCK_TX_ENABLED);
refcount_set(&psock->refcnt, 1);
rcu_assign_sk_user_data(sk, psock);
sock_hold(sk);
return psock;
}
EXPORT_SYMBOL_GPL(sk_psock_init);
struct sk_psock_link *sk_psock_link_pop(struct sk_psock *psock)
{
struct sk_psock_link *link;
spin_lock_bh(&psock->link_lock);
link = list_first_entry_or_null(&psock->link, struct sk_psock_link,
list);
if (link)
list_del(&link->list);
spin_unlock_bh(&psock->link_lock);
return link;
}
void __sk_psock_purge_ingress_msg(struct sk_psock *psock)
{
struct sk_msg *msg, *tmp;
list_for_each_entry_safe(msg, tmp, &psock->ingress_msg, list) {
list_del(&msg->list);
sk_msg_free(psock->sk, msg);
kfree(msg);
}
}
static void sk_psock_zap_ingress(struct sk_psock *psock)
{
__skb_queue_purge(&psock->ingress_skb);
__sk_psock_purge_ingress_msg(psock);
}
static void sk_psock_link_destroy(struct sk_psock *psock)
{
struct sk_psock_link *link, *tmp;
list_for_each_entry_safe(link, tmp, &psock->link, list) {
list_del(&link->list);
sk_psock_free_link(link);
}
}
static void sk_psock_destroy_deferred(struct work_struct *gc)
{
struct sk_psock *psock = container_of(gc, struct sk_psock, gc);
/* No sk_callback_lock since already detached. */
/* Parser has been stopped */
if (psock->progs.skb_parser)
strp_done(&psock->parser.strp);
cancel_work_sync(&psock->work);
psock_progs_drop(&psock->progs);
sk_psock_link_destroy(psock);
sk_psock_cork_free(psock);
sk_psock_zap_ingress(psock);
if (psock->sk_redir)
sock_put(psock->sk_redir);
sock_put(psock->sk);
kfree(psock);
}
void sk_psock_destroy(struct rcu_head *rcu)
{
struct sk_psock *psock = container_of(rcu, struct sk_psock, rcu);
INIT_WORK(&psock->gc, sk_psock_destroy_deferred);
schedule_work(&psock->gc);
}
EXPORT_SYMBOL_GPL(sk_psock_destroy);
void sk_psock_drop(struct sock *sk, struct sk_psock *psock)
{
sk_psock_cork_free(psock);
sk_psock_zap_ingress(psock);
write_lock_bh(&sk->sk_callback_lock);
sk_psock_restore_proto(sk, psock);
rcu_assign_sk_user_data(sk, NULL);
if (psock->progs.skb_parser)
sk_psock_stop_strp(sk, psock);
write_unlock_bh(&sk->sk_callback_lock);
sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED);
call_rcu(&psock->rcu, sk_psock_destroy);
}
EXPORT_SYMBOL_GPL(sk_psock_drop);
static int sk_psock_map_verd(int verdict, bool redir)
{
switch (verdict) {
case SK_PASS:
return redir ? __SK_REDIRECT : __SK_PASS;
case SK_DROP:
default:
break;
}
return __SK_DROP;
}
int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
struct sk_msg *msg)
{
struct bpf_prog *prog;
int ret;
preempt_disable();
rcu_read_lock();
prog = READ_ONCE(psock->progs.msg_parser);
if (unlikely(!prog)) {
ret = __SK_PASS;
goto out;
}
sk_msg_compute_data_pointers(msg);
msg->sk = sk;
ret = BPF_PROG_RUN(prog, msg);
ret = sk_psock_map_verd(ret, msg->sk_redir);
psock->apply_bytes = msg->apply_bytes;
if (ret == __SK_REDIRECT) {
if (psock->sk_redir)
sock_put(psock->sk_redir);
psock->sk_redir = msg->sk_redir;
if (!psock->sk_redir) {
ret = __SK_DROP;
goto out;
}
sock_hold(psock->sk_redir);
}
out:
rcu_read_unlock();
preempt_enable();
return ret;
}
EXPORT_SYMBOL_GPL(sk_psock_msg_verdict);
static int sk_psock_bpf_run(struct sk_psock *psock, struct bpf_prog *prog,
struct sk_buff *skb)
{
int ret;
skb->sk = psock->sk;
bpf_compute_data_end_sk_skb(skb);
preempt_disable();
ret = BPF_PROG_RUN(prog, skb);
preempt_enable();
/* strparser clones the skb before handing it to a upper layer,
* meaning skb_orphan has been called. We NULL sk on the way out
* to ensure we don't trigger a BUG_ON() in skb/sk operations
* later and because we are not charging the memory of this skb
* to any socket yet.
*/
skb->sk = NULL;
return ret;
}
static struct sk_psock *sk_psock_from_strp(struct strparser *strp)
{
struct sk_psock_parser *parser;
parser = container_of(strp, struct sk_psock_parser, strp);
return container_of(parser, struct sk_psock, parser);
}
static void sk_psock_verdict_apply(struct sk_psock *psock,
struct sk_buff *skb, int verdict)
{
struct sk_psock *psock_other;
struct sock *sk_other;
bool ingress;
switch (verdict) {
case __SK_PASS:
sk_other = psock->sk;
if (sock_flag(sk_other, SOCK_DEAD) ||
!sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)) {
goto out_free;
}
if (atomic_read(&sk_other->sk_rmem_alloc) <=
sk_other->sk_rcvbuf) {
struct tcp_skb_cb *tcp = TCP_SKB_CB(skb);
tcp->bpf.flags |= BPF_F_INGRESS;
skb_queue_tail(&psock->ingress_skb, skb);
schedule_work(&psock->work);
break;
}
goto out_free;
case __SK_REDIRECT:
sk_other = tcp_skb_bpf_redirect_fetch(skb);
if (unlikely(!sk_other))
goto out_free;
psock_other = sk_psock(sk_other);
if (!psock_other || sock_flag(sk_other, SOCK_DEAD) ||
!sk_psock_test_state(psock_other, SK_PSOCK_TX_ENABLED))
goto out_free;
ingress = tcp_skb_bpf_ingress(skb);
if ((!ingress && sock_writeable(sk_other)) ||
(ingress &&
atomic_read(&sk_other->sk_rmem_alloc) <=
sk_other->sk_rcvbuf)) {
if (!ingress)
skb_set_owner_w(skb, sk_other);
skb_queue_tail(&psock_other->ingress_skb, skb);
schedule_work(&psock_other->work);
break;
}
/* fall-through */
case __SK_DROP:
/* fall-through */
default:
out_free:
kfree_skb(skb);
}
}
static void sk_psock_strp_read(struct strparser *strp, struct sk_buff *skb)
{
struct sk_psock *psock = sk_psock_from_strp(strp);
struct bpf_prog *prog;
int ret = __SK_DROP;
rcu_read_lock();
prog = READ_ONCE(psock->progs.skb_verdict);
if (likely(prog)) {
skb_orphan(skb);
tcp_skb_bpf_redirect_clear(skb);
ret = sk_psock_bpf_run(psock, prog, skb);
ret = sk_psock_map_verd(ret, tcp_skb_bpf_redirect_fetch(skb));
}
rcu_read_unlock();
sk_psock_verdict_apply(psock, skb, ret);
}
static int sk_psock_strp_read_done(struct strparser *strp, int err)
{
return err;
}
static int sk_psock_strp_parse(struct strparser *strp, struct sk_buff *skb)
{
struct sk_psock *psock = sk_psock_from_strp(strp);
struct bpf_prog *prog;
int ret = skb->len;
rcu_read_lock();
prog = READ_ONCE(psock->progs.skb_parser);
if (likely(prog))
ret = sk_psock_bpf_run(psock, prog, skb);
rcu_read_unlock();
return ret;
}
/* Called with socket lock held. */
static void sk_psock_strp_data_ready(struct sock *sk)
{
struct sk_psock *psock;
rcu_read_lock();
psock = sk_psock(sk);
if (likely(psock)) {
write_lock_bh(&sk->sk_callback_lock);
strp_data_ready(&psock->parser.strp);
write_unlock_bh(&sk->sk_callback_lock);
}
rcu_read_unlock();
}
static void sk_psock_write_space(struct sock *sk)
{
struct sk_psock *psock;
void (*write_space)(struct sock *sk);
rcu_read_lock();
psock = sk_psock(sk);
if (likely(psock && sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)))
schedule_work(&psock->work);
write_space = psock->saved_write_space;
rcu_read_unlock();
write_space(sk);
}
int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock)
{
static const struct strp_callbacks cb = {
.rcv_msg = sk_psock_strp_read,
.read_sock_done = sk_psock_strp_read_done,
.parse_msg = sk_psock_strp_parse,
};
psock->parser.enabled = false;
return strp_init(&psock->parser.strp, sk, &cb);
}
void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
{
struct sk_psock_parser *parser = &psock->parser;
if (parser->enabled)
return;
parser->saved_data_ready = sk->sk_data_ready;
sk->sk_data_ready = sk_psock_strp_data_ready;
sk->sk_write_space = sk_psock_write_space;
parser->enabled = true;
}
void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
{
struct sk_psock_parser *parser = &psock->parser;
if (!parser->enabled)
return;
sk->sk_data_ready = parser->saved_data_ready;
parser->saved_data_ready = NULL;
strp_stop(&parser->strp);
parser->enabled = false;
}