[PATCH 4.9 130/172] tipc: allocate user memory with GFP_KERNEL flag

From: Greg Kroah-Hartman
Date: Mon Jul 03 2017 - 10:09:38 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@xxxxxxxxxxxx>


[ Upstream commit 57d5f64d83ab5b5a5118b1597386dd76eaf4340d ]

Until now, we allocate memory always with GFP_ATOMIC flag.
When the system is under memory pressure and a user tries to send,
the send fails due to low memory. However, the user application
can wait for free memory if we allocate it using GFP_KERNEL flag.

In this commit, we use allocate memory with GFP_KERNEL for all user
allocation.

Reported-by: Rune Torgersen <runet@xxxxxxxxxxxx>
Acked-by: Jon Maloy <jon.maloy@xxxxxxxxxxxx>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/tipc/discover.c | 4 ++--
net/tipc/link.c | 2 +-
net/tipc/msg.c | 16 ++++++++--------
net/tipc/msg.h | 2 +-
net/tipc/name_distr.c | 2 +-
5 files changed, 13 insertions(+), 13 deletions(-)

--- a/net/tipc/discover.c
+++ b/net/tipc/discover.c
@@ -169,7 +169,7 @@ void tipc_disc_rcv(struct net *net, stru

/* Send response, if necessary */
if (respond && (mtyp == DSC_REQ_MSG)) {
- rskb = tipc_buf_acquire(MAX_H_SIZE);
+ rskb = tipc_buf_acquire(MAX_H_SIZE, GFP_ATOMIC);
if (!rskb)
return;
tipc_disc_init_msg(net, rskb, DSC_RESP_MSG, bearer);
@@ -278,7 +278,7 @@ int tipc_disc_create(struct net *net, st
req = kmalloc(sizeof(*req), GFP_ATOMIC);
if (!req)
return -ENOMEM;
- req->buf = tipc_buf_acquire(MAX_H_SIZE);
+ req->buf = tipc_buf_acquire(MAX_H_SIZE, GFP_ATOMIC);
if (!req->buf) {
kfree(req);
return -ENOMEM;
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1395,7 +1395,7 @@ tnl:
msg_set_seqno(hdr, seqno++);
pktlen = msg_size(hdr);
msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
- tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE);
+ tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
if (!tnlskb) {
pr_warn("%sunable to send packet\n", link_co_err);
return;
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -58,12 +58,12 @@ static unsigned int align(unsigned int i
* NOTE: Headroom is reserved to allow prepending of a data link header.
* There may also be unrequested tailroom present at the buffer's end.
*/
-struct sk_buff *tipc_buf_acquire(u32 size)
+struct sk_buff *tipc_buf_acquire(u32 size, gfp_t gfp)
{
struct sk_buff *skb;
unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;

- skb = alloc_skb_fclone(buf_size, GFP_ATOMIC);
+ skb = alloc_skb_fclone(buf_size, gfp);
if (skb) {
skb_reserve(skb, BUF_HEADROOM);
skb_put(skb, size);
@@ -95,7 +95,7 @@ struct sk_buff *tipc_msg_create(uint use
struct tipc_msg *msg;
struct sk_buff *buf;

- buf = tipc_buf_acquire(hdr_sz + data_sz);
+ buf = tipc_buf_acquire(hdr_sz + data_sz, GFP_ATOMIC);
if (unlikely(!buf))
return NULL;

@@ -261,7 +261,7 @@ int tipc_msg_build(struct tipc_msg *mhdr

/* No fragmentation needed? */
if (likely(msz <= pktmax)) {
- skb = tipc_buf_acquire(msz);
+ skb = tipc_buf_acquire(msz, GFP_KERNEL);
if (unlikely(!skb))
return -ENOMEM;
skb_orphan(skb);
@@ -282,7 +282,7 @@ int tipc_msg_build(struct tipc_msg *mhdr
msg_set_importance(&pkthdr, msg_importance(mhdr));

/* Prepare first fragment */
- skb = tipc_buf_acquire(pktmax);
+ skb = tipc_buf_acquire(pktmax, GFP_KERNEL);
if (!skb)
return -ENOMEM;
skb_orphan(skb);
@@ -313,7 +313,7 @@ int tipc_msg_build(struct tipc_msg *mhdr
pktsz = drem + INT_H_SIZE;
else
pktsz = pktmax;
- skb = tipc_buf_acquire(pktsz);
+ skb = tipc_buf_acquire(pktsz, GFP_KERNEL);
if (!skb) {
rc = -ENOMEM;
goto error;
@@ -448,7 +448,7 @@ bool tipc_msg_make_bundle(struct sk_buff
if (msz > (max / 2))
return false;

- _skb = tipc_buf_acquire(max);
+ _skb = tipc_buf_acquire(max, GFP_ATOMIC);
if (!_skb)
return false;

@@ -496,7 +496,7 @@ bool tipc_msg_reverse(u32 own_node, str

/* Never return SHORT header; expand by replacing buffer if necessary */
if (msg_short(hdr)) {
- *skb = tipc_buf_acquire(BASIC_H_SIZE + dlen);
+ *skb = tipc_buf_acquire(BASIC_H_SIZE + dlen, GFP_ATOMIC);
if (!*skb)
goto exit;
memcpy((*skb)->data + BASIC_H_SIZE, msg_data(hdr), dlen);
--- a/net/tipc/msg.h
+++ b/net/tipc/msg.h
@@ -820,7 +820,7 @@ static inline bool msg_is_reset(struct t
return (msg_user(hdr) == LINK_PROTOCOL) && (msg_type(hdr) == RESET_MSG);
}

-struct sk_buff *tipc_buf_acquire(u32 size);
+struct sk_buff *tipc_buf_acquire(u32 size, gfp_t gfp);
bool tipc_msg_validate(struct sk_buff *skb);
bool tipc_msg_reverse(u32 own_addr, struct sk_buff **skb, int err);
void tipc_msg_init(u32 own_addr, struct tipc_msg *m, u32 user, u32 type,
--- a/net/tipc/name_distr.c
+++ b/net/tipc/name_distr.c
@@ -69,7 +69,7 @@ static struct sk_buff *named_prepare_buf
u32 dest)
{
struct tipc_net *tn = net_generic(net, tipc_net_id);
- struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size);
+ struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size, GFP_ATOMIC);
struct tipc_msg *msg;

if (buf != NULL) {