Unverified Commit fec67c41 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!8336 tcp: fix page frag corruption on page fault 

Merge Pull Request from: @ci-robot 
 
PR sync from: Liu Jian <liujian56@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/CHPHJYJ4A5OH4MACZV7F7GW5THIP2ROK/ 
 
https://gitee.com/src-openeuler/kernel/issues/I9S257 
 
Link:https://gitee.com/openeuler/kernel/pulls/8336

 

Reviewed-by: default avatarLiu YongQiang <liuyongqiang13@huawei.com>
Reviewed-by: default avatarYue Haibing <yuehaibing@huawei.com>
Signed-off-by: default avatarZhang Changzhong <zhangchangzhong@huawei.com>
parents 931ac8ed ff3f2c8f

include/net/sock.h

+8 −5
Original line number Diff line number Diff line
@@ -2333,16 +2333,19 @@ struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, 
 * @sk: socket

 *

 * Use the per task page_frag instead of the per socket one for

 * optimization when we know that we're in the normal context and owns

 * optimization when we know that we're in process context and own

 * everything that's associated with %current.

 *

 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest

 * inside other socket operations and end up recursing into sk_page_frag()

 * while it's already in use.

 * Both direct reclaim and page faults can nest inside other

 * socket operations and end up recursing into sk_page_frag()

 * while it's already in use: explicitly avoid task page_frag

 * usage if the caller is potentially doing any of them.

 * This assumes that page fault handlers use the GFP_NOFS flags.

 */

static inline struct page_frag *sk_page_frag(struct sock *sk)

{

	if (gfpflags_normal_context(sk->sk_allocation))

	if ((sk->sk_allocation & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC | __GFP_FS)) ==

	    (__GFP_DIRECT_RECLAIM | __GFP_FS))

		return &current->task_frag;



	return &sk->sk_frag;