From 8f6936f4d29aa14e54a2470b954a2e1f96322988 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Mon, 4 Feb 2008 22:29:41 -0800 Subject: [PATCH] revert "capabilities: clean up file capability reading" Revert b68680e4731abbd78863063aaa0dca2a6d8cc723 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 b68680e4731abbd78863063aaa0dca2a6d8cc723 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 Cc: Serge Hallyn Cc: Chris Wright Cc: James Morris Cc: Casey Schaufler Cc: Andrew Morgan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/capability.h | 6 ++++-- security/commoncap.c | 23 ++++++++--------------- 2 files changed, 12 insertions(+), 17 deletions(-) diff --git a/include/linux/capability.h b/include/linux/capability.h index bb017edffd56..7a8d7ade28a0 100644 --- a/include/linux/capability.h +++ b/include/linux/capability.h @@ -56,8 +56,10 @@ typedef struct __user_cap_data_struct { struct vfs_cap_data { __u32 magic_etc; /* Little endian */ - __u32 permitted; /* Little endian */ - __u32 inheritable; /* Little endian */ + struct { + __u32 permitted; /* Little endian */ + __u32 inheritable; /* Little endian */ + } data[1]; }; #ifdef __KERNEL__ diff --git a/security/commoncap.c b/security/commoncap.c index ea61bc73f6d3..b06617b35b93 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -197,8 +197,7 @@ int cap_inode_killpriv(struct dentry *dentry) return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS); } -static inline int cap_from_disk(struct vfs_cap_data *caps, - struct linux_binprm *bprm, +static inline int cap_from_disk(__le32 *caps, struct linux_binprm *bprm, int size) { __u32 magic_etc; @@ -206,7 +205,7 @@ static inline int cap_from_disk(struct vfs_cap_data *caps, if (size != XATTR_CAPS_SZ) return -EINVAL; - magic_etc = le32_to_cpu(caps->magic_etc); + magic_etc = le32_to_cpu(caps[0]); switch ((magic_etc & VFS_CAP_REVISION_MASK)) { case VFS_CAP_REVISION: @@ -214,8 +213,8 @@ static inline int cap_from_disk(struct vfs_cap_data *caps, bprm->cap_effective = true; else bprm->cap_effective = false; - bprm->cap_permitted = to_cap_t(le32_to_cpu(caps->permitted)); - bprm->cap_inheritable = to_cap_t(le32_to_cpu(caps->inheritable)); + bprm->cap_permitted = to_cap_t(le32_to_cpu(caps[1])); + bprm->cap_inheritable = to_cap_t(le32_to_cpu(caps[2])); return 0; default: return -EINVAL; @@ -227,7 +226,7 @@ static int get_file_caps(struct linux_binprm *bprm) { struct dentry *dentry; int rc = 0; - struct vfs_cap_data incaps; + __le32 v1caps[XATTR_CAPS_SZ]; struct inode *inode; 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) goto out; - 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; - } + rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, &v1caps, + XATTR_CAPS_SZ); if (rc == -ENODATA || rc == -EOPNOTSUPP) { /* no data, that's ok */ rc = 0; @@ -256,7 +249,7 @@ static int get_file_caps(struct linux_binprm *bprm) if (rc < 0) goto out; - rc = cap_from_disk(&incaps, bprm, rc); + rc = cap_from_disk(v1caps, bprm, rc); if (rc) printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n", __FUNCTION__, rc, bprm->filename); -- 2.20.1