From: Christian Brauner brauner@kernel.org
commit 8d84e39d76bd83474b26cb44f4b338635676e7e8 upstream.
Now that we made the VFS setgid checking consistent an inode can't be marked security irrelevant even if the setgid bit is still set. Make this function consistent with all other helpers.
Note that enforcing consistent setgid stripping checks for file modification and mode- and ownership changes will cause the setgid bit to be lost in more cases than useed to be the case. If an unprivileged user wrote to a non-executable setgid file that they don't have privilege over the setgid bit will be dropped. This will lead to temporary failures in some xfstests until they have been updated.
Reported-by: Miklos Szeredi miklos@szeredi.hu Signed-off-by: Christian Brauner (Microsoft) brauner@kernel.org Signed-off-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/linux/fs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3549,7 +3549,7 @@ int __init list_bdev_fs_names(char *buf,
static inline bool is_sxid(umode_t mode) { - return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP)); + return mode & (S_ISUID | S_ISGID); }
static inline int check_sticky(struct user_namespace *mnt_userns,