Commit b68680e4 authored by Serge E. Hallyn's avatar Serge E. Hallyn Committed by Linus Torvalds
Browse files

capabilities: clean up file capability reading 



Simplify the vfs_cap_data structure.

Also fix get_file_caps which was declaring
__le32 v1caps[XATTR_CAPS_SZ] on the stack, but
XATTR_CAPS_SZ is already * sizeof(__le32).

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: default avatarSerge E. Hallyn <serue@us.ibm.com>
Cc: Andrew Morgan <morgan@kernel.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b9049e23

include/linux/capability.h

+2 −4
Original line number Diff line number Diff line
@@ -56,10 +56,8 @@ typedef struct __user_cap_data_struct { 


struct vfs_cap_data {

	__u32 magic_etc;  /* Little endian */

	struct {

	__u32 permitted;    /* Little endian */

	__u32 inheritable;  /* Little endian */

	} data[1];

};



#ifdef __KERNEL__

security/commoncap.c

+15 −8
Original line number Diff line number Diff line
@@ -190,7 +190,8 @@ int cap_inode_killpriv(struct dentry *dentry) 
	return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS);

}



static inline int cap_from_disk(__le32 *caps, struct linux_binprm *bprm,

static inline int cap_from_disk(struct vfs_cap_data *caps,

				struct linux_binprm *bprm,

				int size)

{

	__u32 magic_etc;
@@ -198,7 +199,7 @@ static inline int cap_from_disk(__le32 *caps, struct linux_binprm *bprm, 
	if (size != XATTR_CAPS_SZ)

		return -EINVAL;



	magic_etc = le32_to_cpu(caps[0]);

	magic_etc = le32_to_cpu(caps->magic_etc);



	switch ((magic_etc & VFS_CAP_REVISION_MASK)) {

	case VFS_CAP_REVISION:
@@ -206,8 +207,8 @@ static inline int cap_from_disk(__le32 *caps, struct linux_binprm *bprm, 
			bprm->cap_effective = true;

		else

			bprm->cap_effective = false;

		bprm->cap_permitted = to_cap_t( le32_to_cpu(caps[1]) );

		bprm->cap_inheritable = to_cap_t( le32_to_cpu(caps[2]) );

		bprm->cap_permitted = to_cap_t(le32_to_cpu(caps->permitted));

		bprm->cap_inheritable = to_cap_t(le32_to_cpu(caps->inheritable));

		return 0;

	default:

		return -EINVAL;
@@ -219,7 +220,7 @@ static int get_file_caps(struct linux_binprm *bprm) 
{

	struct dentry *dentry;

	int rc = 0;

	__le32 v1caps[XATTR_CAPS_SZ];

	struct vfs_cap_data incaps;

	struct inode *inode;



	if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) {
@@ -232,8 +233,14 @@ static int get_file_caps(struct linux_binprm *bprm) 
	if (!inode->i_op || !inode->i_op->getxattr)

		goto out;



	rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, &v1caps,

							XATTR_CAPS_SZ);

	rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0);

	if (rc > 0) {

		if (rc == XATTR_CAPS_SZ)

			rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS,

						&incaps, XATTR_CAPS_SZ);

		else

			rc = -EINVAL;

	}

	if (rc == -ENODATA || rc == -EOPNOTSUPP) {

		/* no data, that's ok */

		rc = 0;
@@ -242,7 +249,7 @@ static int get_file_caps(struct linux_binprm *bprm) 
	if (rc < 0)

		goto out;



	rc = cap_from_disk(v1caps, bprm, rc);

	rc = cap_from_disk(&incaps, bprm, rc);

	if (rc)

		printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n",

			__FUNCTION__, rc, bprm->filename);

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