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
| ||
|
Date: Thu, 1 Jan 2015 14:07:42 +0900 From: Seunghun Lee <waydi1@...il.com> To: miklos@...redi.hu Cc: linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org, Seunghun Lee <waydi1@...il.com> Subject: [PATCH] ovl: Prevent rw remount when it should be ro mount Overlayfs should be mounted read-only when upper fs is r/o or nonexistend. But now it can be remounted read-write and this can causes kernel panic. So we should prevent read-write remount when the above situation. Signed-off-by: Seunghun Lee <waydi1@...il.com> --- fs/overlayfs/super.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 84f3144..1faa5e5 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -522,6 +522,14 @@ static int ovl_show_options(struct seq_file *m, struct dentry *dentry) return 0; } +static int squashfs_remount(struct super_block *sb, int *flags, char *data) +{ + if (!ufs->upper_mnt || (ufs->upper_mnt->mnt_sb->s_flags & MS_RDONLY)) + *flags |= MS_RDONLY; + + return 0; +} + static const struct super_operations ovl_super_operations = { .put_super = ovl_put_super, .statfs = ovl_statfs, -- 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/
Powered by blists - more mailing lists