linux-kernel - [PATCH] fs/coredump: Use kmap_local

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>] [day] [month] [year] [list]

Message-Id: <20210203223328.558945-1-ira.weiny@intel.com>
Date:   Wed,  3 Feb 2021 14:33:28 -0800
From:   ira.weiny@...el.com
To:     Alexander Viro <viro@...iv.linux.org.uk>
Cc:     Ira Weiny <ira.weiny@...el.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org
Subject: [PATCH] fs/coredump: Use kmap_local_page()

From: Ira Weiny <ira.weiny@...el.com>

In dump_user_range() there is no reason for the mapping to be global.
Use kmap_local_page() rather than kmap.

Cc: Andrew Morton <akpm@...ux-foundation.org>
Cc: linux-kernel@...r.kernel.org
Cc: linux-fsdevel@...r.kernel.org
Signed-off-by: Ira Weiny <ira.weiny@...el.com>
---
 fs/coredump.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/coredump.c b/fs/coredump.c
index a2f6ecc8e345..53f63e176a2a 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -894,10 +894,10 @@ int dump_user_range(struct coredump_params *cprm, unsigned long start,
 		 */
 		page = get_dump_page(addr);
 		if (page) {
-			void *kaddr = kmap(page);
+			void *kaddr = kmap_local_page(page);
 
 			stop = !dump_emit(cprm, kaddr, PAGE_SIZE);
-			kunmap(page);
+			kunmap_local(kaddr);
 			put_page(page);
 		} else {
 			stop = !dump_skip(cprm, PAGE_SIZE);
-- 
2.28.0.rc0.12.gb6a658bd00c9