linux-kernel - [PATCH 2/8] swap: lock i_mutex for swap_writepage direct

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <a59510f4552a5d3557958cdb0ce1b23b3abfc75b.1418618044.git.osandov@osandov.com>
Date:	Sun, 14 Dec 2014 21:26:56 -0800
From:	Omar Sandoval <osandov@...ndov.com>
To:	Alexander Viro <viro@...iv.linux.org.uk>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Trond Myklebust <trond.myklebust@...marydata.com>,
	Christoph Hellwig <hch@...radead.org>,
	David Sterba <dsterba@...e.cz>, linux-fsdevel@...r.kernel.org,
	linux-mm@...ck.org, linux-nfs@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc:	Omar Sandoval <osandov@...ndov.com>
Subject: [PATCH 2/8] swap: lock i_mutex for swap_writepage direct_IO

The generic write code locks i_mutex for a direct_IO. Swap-over-NFS
doesn't grab the mutex because nfs_direct_IO doesn't expect i_mutex to
be held, but most direct_IO implementations do.

Signed-off-by: Omar Sandoval <osandov@...ndov.com>
---
 mm/page_io.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/mm/page_io.c b/mm/page_io.c
index 955db8b..1630ac0 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -263,6 +263,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 	if (sis->flags & SWP_FILE) {
 		struct kiocb kiocb;
 		struct file *swap_file = sis->swap_file;
+		struct inode *inode = file_inode(swap_file);
 		struct address_space *mapping = swap_file->f_mapping;
 		struct bio_vec bv = {
 			.bv_page = page,
@@ -283,9 +284,11 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 
 		set_page_writeback(page);
 		unlock_page(page);
+		mutex_lock(&inode->i_mutex);
 		ret = mapping->a_ops->direct_IO(ITER_BVEC | WRITE,
 						&kiocb, &from,
 						kiocb.ki_pos);
+		mutex_unlock(&inode->i_mutex);
 		if (ret == PAGE_SIZE) {
 			count_vm_event(PSWPOUT);
 			ret = 0;
-- 
2.1.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/