revert "capabilities: clean up file capability reading"

Revert b68680e473 to make way for the next
patch: "Add 64-bit capability support to the kernel".

We want to keep the vfs_cap_data.data[] structure, using two 'data's for
64-bit caps (and later three for 96-bit caps), whereas
b68680e473 had gotten rid of the 'data' struct
made its members inline.

The 64-bit caps patch keeps the stack abuse fix at get_file_caps(), which was
the more important part of that patch.

[akpm@linux-foundation.org: coding-style fixes]
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Andrew Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andrew Morton 2008-02-04 22:29:41 -08:00 committed by Linus Torvalds
parent 4bea58053f
commit 8f6936f4d2
2 changed files with 12 additions and 17 deletions

View file

@ -56,8 +56,10 @@ typedef struct __user_cap_data_struct {
struct vfs_cap_data { struct vfs_cap_data {
__u32 magic_etc; /* Little endian */ __u32 magic_etc; /* Little endian */
__u32 permitted; /* Little endian */ struct {
__u32 inheritable; /* Little endian */ __u32 permitted; /* Little endian */
__u32 inheritable; /* Little endian */
} data[1];
}; };
#ifdef __KERNEL__ #ifdef __KERNEL__

View file

@ -197,8 +197,7 @@ int cap_inode_killpriv(struct dentry *dentry)
return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS); return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS);
} }
static inline int cap_from_disk(struct vfs_cap_data *caps, static inline int cap_from_disk(__le32 *caps, struct linux_binprm *bprm,
struct linux_binprm *bprm,
int size) int size)
{ {
__u32 magic_etc; __u32 magic_etc;
@ -206,7 +205,7 @@ static inline int cap_from_disk(struct vfs_cap_data *caps,
if (size != XATTR_CAPS_SZ) if (size != XATTR_CAPS_SZ)
return -EINVAL; return -EINVAL;
magic_etc = le32_to_cpu(caps->magic_etc); magic_etc = le32_to_cpu(caps[0]);
switch ((magic_etc & VFS_CAP_REVISION_MASK)) { switch ((magic_etc & VFS_CAP_REVISION_MASK)) {
case VFS_CAP_REVISION: case VFS_CAP_REVISION:
@ -214,8 +213,8 @@ static inline int cap_from_disk(struct vfs_cap_data *caps,
bprm->cap_effective = true; bprm->cap_effective = true;
else else
bprm->cap_effective = false; bprm->cap_effective = false;
bprm->cap_permitted = to_cap_t(le32_to_cpu(caps->permitted)); bprm->cap_permitted = to_cap_t(le32_to_cpu(caps[1]));
bprm->cap_inheritable = to_cap_t(le32_to_cpu(caps->inheritable)); bprm->cap_inheritable = to_cap_t(le32_to_cpu(caps[2]));
return 0; return 0;
default: default:
return -EINVAL; return -EINVAL;
@ -227,7 +226,7 @@ static int get_file_caps(struct linux_binprm *bprm)
{ {
struct dentry *dentry; struct dentry *dentry;
int rc = 0; int rc = 0;
struct vfs_cap_data incaps; __le32 v1caps[XATTR_CAPS_SZ];
struct inode *inode; struct inode *inode;
if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) { if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) {
@ -240,14 +239,8 @@ static int get_file_caps(struct linux_binprm *bprm)
if (!inode->i_op || !inode->i_op->getxattr) if (!inode->i_op || !inode->i_op->getxattr)
goto out; goto out;
rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0); rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, &v1caps,
if (rc > 0) { XATTR_CAPS_SZ);
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) { if (rc == -ENODATA || rc == -EOPNOTSUPP) {
/* no data, that's ok */ /* no data, that's ok */
rc = 0; rc = 0;
@ -256,7 +249,7 @@ static int get_file_caps(struct linux_binprm *bprm)
if (rc < 0) if (rc < 0)
goto out; goto out;
rc = cap_from_disk(&incaps, bprm, rc); rc = cap_from_disk(v1caps, bprm, rc);
if (rc) if (rc)
printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n", printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n",
__FUNCTION__, rc, bprm->filename); __FUNCTION__, rc, bprm->filename);