From 4bdac2526df0ea4fad8a78958fe462f1ab4a17dd Mon Sep 17 00:00:00 2001 From: Ian Kent Date: Tue, 21 Aug 2018 21:51:45 -0700 Subject: autofs: fix autofs_sbi() does not check super block type commit 0633da48f0793aeba27f82d30605624416723a91 upstream. autofs_sbi() does not check the superblock magic number to verify it has been given an autofs super block. Backport Note: autofs4 has been renamed to autofs upstream. As a result the upstream patch does not apply cleanly onto 4.14.y. Link: http://lkml.kernel.org/r/153475422934.17131.7563724552005298277.stgit@pluto.themaw.net Reported-by: Signed-off-by: Ian Kent Reviewed-by: Andrew Morton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Zubin Mithra Signed-off-by: Greg Kroah-Hartman --- fs/autofs4/autofs_i.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'fs/autofs4/autofs_i.h') diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index 502d3892d8a4..d71e7ad4d382 100644 --- a/fs/autofs4/autofs_i.h +++ b/fs/autofs4/autofs_i.h @@ -18,6 +18,7 @@ #include #include #include +#include /* This is the range of ioctl() numbers we claim as ours */ #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY @@ -135,7 +136,8 @@ struct autofs_sb_info { static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb) { - return (struct autofs_sb_info *)(sb->s_fs_info); + return sb->s_magic != AUTOFS_SUPER_MAGIC ? + NULL : (struct autofs_sb_info *)(sb->s_fs_info); } static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry) -- cgit v1.2.3