Unverified Commit 26f718c6 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!4019 mm/filemap: avoid buffered read/write race to read inconsistent data 

Merge Pull Request from: @ci-robot 
 
PR sync from: Baokun Li <libaokun1@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/UI4IK5BXOOKYIVD74QR36OY27BRM5MWV/ 
 
https://gitee.com/src-openeuler/kernel/issues/I8RRAT 
 
Link:https://gitee.com/openeuler/kernel/pulls/4019

 

Reviewed-by: default avatarzhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarJialin Zhang <zhangjialin11@huawei.com>
parents ce086fc7 8592c567

mm/filemap.c

+9 −0
Original line number Diff line number Diff line
@@ -2616,6 +2616,15 @@ ssize_t generic_file_buffered_read(struct kiocb *iocb, 


		end_offset = min_t(loff_t, isize, iocb->ki_pos + iter->count);



		/*

		 * Pairs with a barrier in

		 * block_write_end()->mark_buffer_dirty() or other page

		 * dirtying routines like iomap_write_end() to ensure

		 * changes to page contents are visible before we see

		 * increased inode size.

		 */

		smp_rmb();



		while ((iocb->ki_pos >> PAGE_SHIFT) + pg_nr >

		       (end_offset + PAGE_SIZE - 1) >> PAGE_SHIFT)

			put_page(pages[--pg_nr]);