From: Dan Carpenter <dan.carpenter@oracle.com>
To: Namjae Jeon <namjae.jeon@samsung.com>,
Tetsuhiro Kohada <kohada.t2@gmail.com>
Cc: Sungjong Seo <sj1557.seo@samsung.com>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
kernel-janitors@vger.kernel.org
Subject: [PATCH] exfat: Fix pontential use after free in exfat_load_upcase_table()
Date: Mon, 8 Jun 2020 17:16:29 +0300 [thread overview]
Message-ID: <20200608141629.GA1912173@mwanda> (raw)
This code calls brelse(bh) and then dereferences "bh" on the next line
resulting in a possible use after free. The brelse() should just be
moved down a line.
Fixes: b676fdbcf4c8 ("exfat: standardize checksum calculation")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
fs/exfat/nls.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/exfat/nls.c b/fs/exfat/nls.c
index c1ec056954974..57b5a7a4d1f7a 100644
--- a/fs/exfat/nls.c
+++ b/fs/exfat/nls.c
@@ -692,8 +692,8 @@ static int exfat_load_upcase_table(struct super_block *sb,
index++;
}
}
- brelse(bh);
chksum = exfat_calc_chksum32(bh->b_data, i, chksum, CS_DEFAULT);
+ brelse(bh);
}
if (index >= 0xFFFF && utbl_checksum == chksum)
--
2.26.2
next reply other threads:[~2020-06-08 14:16 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20200608141649epcas1p14558f3552afb0fcd3cd32a8c09afb880@epcas1p1.samsung.com>
2020-06-08 14:16 ` Dan Carpenter [this message]
2020-06-09 0:37 ` [PATCH] exfat: Fix pontential use after free in exfat_load_upcase_table() Namjae Jeon
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