From: "Valdis Klētnieks" <valdis.kletnieks@vt.edu>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Sasha Levin <alexander.levin@microsoft.com>,
Christoph Hellwig <hch@infradead.org>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] drivers/staging/exfat - by default, prohibit mount of fat/vfat
Date: Fri, 30 Aug 2019 12:42:39 -0400 [thread overview]
Message-ID: <245727.1567183359@turing-police> (raw)
Concerns have been raised about the exfat driver accidentally mounting
fat/vfat file systems. Add an extra configure option to help prevent that.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
diff --git a/drivers/staging/exfat/Kconfig b/drivers/staging/exfat/Kconfig
index 78b32aa2ca19..1df177b1dc72 100644
--- a/drivers/staging/exfat/Kconfig
+++ b/drivers/staging/exfat/Kconfig
@@ -4,6 +4,14 @@ config EXFAT_FS
help
This adds support for the exFAT file system.
+config EXFAT_DONT_MOUNT_VFAT
+ bool "Prohibit mounting of fat/vfat filesysems by exFAT"
+ default y
+ help
+ By default, the exFAT driver will only mount exFAT filesystems, and refuse
+ to mount fat/vfat filesystems. Set this to 'n' to allow the exFAT driver
+ to mount these filesystems.
+
config EXFAT_DISCARD
bool "enable discard support"
depends on EXFAT_FS
diff --git a/drivers/staging/exfat/exfat_super.c b/drivers/staging/exfat/exfat_super.c
index 5b5c2ca8c9aa..7fdb5b8bc928 100644
--- a/drivers/staging/exfat/exfat_super.c
+++ b/drivers/staging/exfat/exfat_super.c
@@ -486,10 +486,16 @@ static int ffsMountVol(struct super_block *sb)
break;
if (i < 53) {
+#ifdef CONFIG_EXFAT_DONT_MOUNT_VFAT
+ ret = -EINVAL;
+ printk(KERN_INFO "EXFAT: Attempted to mount VFAT filesystem\n");
+ goto out;
+#else
if (GET16(p_pbr->bpb + 11)) /* num_fat_sectors */
ret = fat16_mount(sb, p_pbr);
else
ret = fat32_mount(sb, p_pbr);
+#endif
} else {
ret = exfat_mount(sb, p_pbr);
}
next reply other threads:[~2019-08-30 16:42 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-30 16:42 Valdis Klētnieks [this message]
2019-08-30 16:45 ` [PATCH] drivers/staging/exfat - by default, prohibit mount of fat/vfat Christoph Hellwig
2019-08-31 0:48 ` Valdis Klētnieks
2019-08-31 6:46 ` Christoph Hellwig
2019-08-31 10:25 ` Valdis Klētnieks
2019-08-31 14:24 ` Andy Shevchenko
2019-08-31 14:51 ` Valdis Klētnieks
2019-09-01 1:07 ` Dave Chinner
2019-09-01 1:37 ` Gao Xiang
2019-09-01 3:05 ` Al Viro
2019-09-01 3:26 ` Gao Xiang
2019-09-01 3:37 ` Valdis Klētnieks
2019-09-01 22:43 ` Dave Chinner
2019-09-01 23:13 ` Valdis Klētnieks
2019-09-02 7:38 ` Christoph Hellwig
2019-09-02 7:35 ` Christoph Hellwig
2019-09-02 15:25 ` Greg Kroah-Hartman
2019-09-02 19:00 ` Valdis Klētnieks
2019-09-02 19:06 ` Greg Kroah-Hartman
2019-09-08 10:50 ` OGAWA Hirofumi
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