linux-hardening - [PATCH] mtd: physmap: physmap-bt1-rom: Fix unintentional stack access

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-next>] [day] [month] [year] [list]

Date:   Fri, 12 Feb 2021 04:40:22 -0600
From:   "Gustavo A. R. Silva" <gustavoars@...nel.org>
To:     Miquel Raynal <miquel.raynal@...tlin.com>,
        Richard Weinberger <richard@....at>,
        Vignesh Raghavendra <vigneshr@...com>,
        Serge Semin <Sergey.Semin@...kalelectronics.ru>
Cc:     linux-mtd@...ts.infradead.org, linux-kernel@...r.kernel.org,
        "Gustavo A. R. Silva" <gustavoars@...nel.org>,
        Kees Cook <keescook@...omium.org>,
        linux-hardening@...r.kernel.org
Subject: [PATCH] mtd: physmap: physmap-bt1-rom: Fix unintentional stack access

Cast &data to (char *) in order to avoid unintentionally accessing
the stack.

Notice that data is of type u32, so any increment to &data
will be in the order of 4-byte chunks, and this piece of code
is actually intended to be a byte offset.

Fixes: b3e79e7682e0 ("mtd: physmap: Add Baikal-T1 physically mapped ROM support")
Addresses-Coverity-ID: 1497765 ("Out-of-bounds access")
Cc: stable@...r.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@...nel.org>
---
 drivers/mtd/maps/physmap-bt1-rom.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/maps/physmap-bt1-rom.c b/drivers/mtd/maps/physmap-bt1-rom.c
index a35450002284..58782cfaf71c 100644
--- a/drivers/mtd/maps/physmap-bt1-rom.c
+++ b/drivers/mtd/maps/physmap-bt1-rom.c
@@ -79,7 +79,7 @@ static void __xipram bt1_rom_map_copy_from(struct map_info *map,
 	if (shift) {
 		chunk = min_t(ssize_t, 4 - shift, len);
 		data = readl_relaxed(src - shift);
-		memcpy(to, &data + shift, chunk);
+		memcpy(to, (char *)&data + shift, chunk);
 		src += chunk;
 		to += chunk;
 		len -= chunk;
-- 
2.27.0