Commit 3318a386 authored Oct 30, 2008 by Serge Hallyn Committed by Linus Torvalds Nov 01, 2008

file caps: always start with clear bprm->caps_*



While Linux doesn't honor setuid on scripts.  However, it mistakenly
behaves differently for file capabilities.

This patch fixes that behavior by making sure that get_file_caps()
begins with empty bprm->caps_*.  That way when a script is loaded,
its bprm->caps_* may be filled when binfmt_misc calls prepare_binprm(),
but they will be cleared again when binfmt_elf calls prepare_binprm()
next to read the interpreter's file capabilities.

Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent e06f42d6

security/commoncap.c

+3 −3

Original line number	Original line	Diff line number	Diff line
	@@ -279,10 +279,10 @@ static int get_file_caps(struct linux_binprm *bprm)
	struct vfs_cap_data vcaps;		struct vfs_cap_data vcaps;
	struct inode *inode;		struct inode *inode;

	if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) {
	bprm_clear_caps(bprm);		bprm_clear_caps(bprm);

			if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
	return 0;		return 0;
	}

	dentry = dget(bprm->file->f_dentry);		dentry = dget(bprm->file->f_dentry);
	inode = dentry->d_inode;		inode = dentry->d_inode;