diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/attr.c | 36 | ||||
| -rw-r--r-- | fs/ioctl.c | 4 | ||||
| -rw-r--r-- | fs/namei.c | 16 | ||||
| -rw-r--r-- | fs/namespace.c | 4 |
4 files changed, 44 insertions, 16 deletions
diff --git a/fs/attr.c b/fs/attr.c index 12ffdb6fb63c..d0b4d34878fb 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -18,6 +18,32 @@ #include <linux/evm.h> #include <linux/ima.h> +static bool chown_ok(const struct inode *inode, kuid_t uid) +{ + if (uid_eq(current_fsuid(), inode->i_uid) && + uid_eq(uid, inode->i_uid)) + return true; + if (capable_wrt_inode_uidgid(inode, CAP_CHOWN)) + return true; + if (uid_eq(inode->i_uid, INVALID_UID) && + ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN)) + return true; + return false; +} + +static bool chgrp_ok(const struct inode *inode, kgid_t gid) +{ + if (uid_eq(current_fsuid(), inode->i_uid) && + (in_group_p(gid) || gid_eq(gid, inode->i_gid))) + return true; + if (capable_wrt_inode_uidgid(inode, CAP_CHOWN)) + return true; + if (gid_eq(inode->i_gid, INVALID_GID) && + ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN)) + return true; + return false; +} + /** * setattr_prepare - check if attribute changes to a dentry are allowed * @dentry: dentry to check @@ -52,17 +78,11 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr) goto kill_priv; /* Make sure a caller can chown. */ - if ((ia_valid & ATTR_UID) && - (!uid_eq(current_fsuid(), inode->i_uid) || - !uid_eq(attr->ia_uid, inode->i_uid)) && - !capable_wrt_inode_uidgid(inode, CAP_CHOWN)) + if ((ia_valid & ATTR_UID) && !chown_ok(inode, attr->ia_uid)) return -EPERM; /* Make sure caller can chgrp. */ - if ((ia_valid & ATTR_GID) && - (!uid_eq(current_fsuid(), inode->i_uid) || - (!in_group_p(attr->ia_gid) && !gid_eq(attr->ia_gid, inode->i_gid))) && - !capable_wrt_inode_uidgid(inode, CAP_CHOWN)) + if ((ia_valid & ATTR_GID) && !chgrp_ok(inode, attr->ia_gid)) return -EPERM; /* Make sure a caller can chmod. */ diff --git a/fs/ioctl.c b/fs/ioctl.c index 4823431d1c9d..b445b13fc59b 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -549,7 +549,7 @@ static int ioctl_fsfreeze(struct file *filp) { struct super_block *sb = file_inode(filp)->i_sb; - if (!capable(CAP_SYS_ADMIN)) + if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) return -EPERM; /* If filesystem doesn't support freeze feature, return. */ @@ -566,7 +566,7 @@ static int ioctl_fsthaw(struct file *filp) { struct super_block *sb = file_inode(filp)->i_sb; - if (!capable(CAP_SYS_ADMIN)) + if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) return -EPERM; /* Thaw */ diff --git a/fs/namei.c b/fs/namei.c index a59968de1636..6df1f61855d6 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -984,13 +984,15 @@ static bool safe_hardlink_source(struct inode *inode) */ static int may_linkat(struct path *link) { - struct inode *inode; + struct inode *inode = link->dentry->d_inode; + + /* Inode writeback is not safe when the uid or gid are invalid. */ + if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid)) + return -EOVERFLOW; if (!sysctl_protected_hardlinks) return 0; - inode = link->dentry->d_inode; - /* Source inode owner (or CAP_FOWNER) can hardlink all they like, * otherwise, it must be a safe source. */ @@ -2747,6 +2749,11 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir) BUG_ON(!inode); BUG_ON(victim->d_parent->d_inode != dir); + + /* Inode writeback is not safe when the uid or gid are invalid. */ + if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid)) + return -EOVERFLOW; + audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); error = inode_permission(dir, MAY_WRITE | MAY_EXEC); @@ -3675,7 +3682,8 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) if (error) return error; - if ((S_ISCHR(mode) || S_ISBLK(mode)) && !capable(CAP_MKNOD)) + if ((S_ISCHR(mode) || S_ISBLK(mode)) && + !ns_capable(dentry->d_sb->s_user_ns, CAP_MKNOD)) return -EPERM; if (!dir->i_op->mknod) diff --git a/fs/namespace.c b/fs/namespace.c index 5f75969adff1..8ddd14806799 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1590,7 +1590,7 @@ static int do_umount(struct mount *mnt, int flags) * Special case for "unmounting" root ... * we just try to remount it readonly. */ - if (!capable(CAP_SYS_ADMIN)) + if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) return -EPERM; down_write(&sb->s_umount); if (!sb_rdonly(sb)) @@ -2333,7 +2333,7 @@ static int do_remount(struct path *path, int ms_flags, int sb_flags, down_write(&sb->s_umount); if (ms_flags & MS_BIND) err = change_mount_flags(path->mnt, ms_flags); - else if (!capable(CAP_SYS_ADMIN)) + else if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) err = -EPERM; else err = do_remount_sb(sb, sb_flags, data, 0); |