diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-10 13:04:49 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-10 13:04:49 -0700 |
commit | abb5a14fa20fdd400995926134b7be9eb8ce6048 (patch) | |
tree | 085add41cae3193b8c8293d25b453fd1ecae0c19 /fs/attr.c | |
parent | 911f9dab301e8583143c7e75b552eadd434ea0a8 (diff) | |
parent | e55f1d1d13e7f1c364672d667d78fd1f640ab9f9 (diff) | |
download | op-kernel-dev-abb5a14fa20fdd400995926134b7be9eb8ce6048.zip op-kernel-dev-abb5a14fa20fdd400995926134b7be9eb8ce6048.tar.gz |
Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
"Assorted misc bits and pieces.
There are several single-topic branches left after this (rename2
series from Miklos, current_time series from Deepa Dinamani, xattr
series from Andreas, uaccess stuff from from me) and I'd prefer to
send those separately"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (39 commits)
proc: switch auxv to use of __mem_open()
hpfs: support FIEMAP
cifs: get rid of unused arguments of CIFSSMBWrite()
posix_acl: uapi header split
posix_acl: xattr representation cleanups
fs/aio.c: eliminate redundant loads in put_aio_ring_file
fs/internal.h: add const to ns_dentry_operations declaration
compat: remove compat_printk()
fs/buffer.c: make __getblk_slow() static
proc: unsigned file descriptors
fs/file: more unsigned file descriptors
fs: compat: remove redundant check of nr_segs
cachefiles: Fix attempt to read i_blocks after deleting file [ver #2]
cifs: don't use memcpy() to copy struct iov_iter
get rid of separate multipage fault-in primitives
fs: Avoid premature clearing of capabilities
fs: Give dentry to inode_change_ok() instead of inode
fuse: Propagate dentry down to inode_change_ok()
ceph: Propagate dentry down to inode_change_ok()
xfs: Propagate dentry down to inode_change_ok()
...
Diffstat (limited to 'fs/attr.c')
-rw-r--r-- | fs/attr.c | 50 |
1 files changed, 38 insertions, 12 deletions
@@ -17,19 +17,22 @@ #include <linux/ima.h> /** - * inode_change_ok - check if attribute changes to an inode are allowed - * @inode: inode to check + * setattr_prepare - check if attribute changes to a dentry are allowed + * @dentry: dentry to check * @attr: attributes to change * * Check if we are allowed to change the attributes contained in @attr - * in the given inode. This includes the normal unix access permission - * checks, as well as checks for rlimits and others. + * in the given dentry. This includes the normal unix access permission + * checks, as well as checks for rlimits and others. The function also clears + * SGID bit from mode if user is not allowed to set it. Also file capabilities + * and IMA extended attributes are cleared if ATTR_KILL_PRIV is set. * * Should be called as the first thing in ->setattr implementations, * possibly after taking additional locks. */ -int inode_change_ok(const struct inode *inode, struct iattr *attr) +int setattr_prepare(struct dentry *dentry, struct iattr *attr) { + struct inode *inode = d_inode(dentry); unsigned int ia_valid = attr->ia_valid; /* @@ -44,7 +47,7 @@ int inode_change_ok(const struct inode *inode, struct iattr *attr) /* If force is set do it anyway. */ if (ia_valid & ATTR_FORCE) - return 0; + goto kill_priv; /* Make sure a caller can chown. */ if ((ia_valid & ATTR_UID) && @@ -77,9 +80,19 @@ int inode_change_ok(const struct inode *inode, struct iattr *attr) return -EPERM; } +kill_priv: + /* User has permission for the change */ + if (ia_valid & ATTR_KILL_PRIV) { + int error; + + error = security_inode_killpriv(dentry); + if (error) + return error; + } + return 0; } -EXPORT_SYMBOL(inode_change_ok); +EXPORT_SYMBOL(setattr_prepare); /** * inode_newsize_ok - may this inode be truncated to a given size @@ -202,6 +215,21 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de return -EPERM; } + /* + * If utimes(2) and friends are called with times == NULL (or both + * times are UTIME_NOW), then we need to check for write permission + */ + if (ia_valid & ATTR_TOUCH) { + if (IS_IMMUTABLE(inode)) + return -EPERM; + + if (!inode_owner_or_capable(inode)) { + error = inode_permission(inode, MAY_WRITE); + if (error) + return error; + } + } + if ((ia_valid & ATTR_MODE)) { umode_t amode = attr->ia_mode; /* Flag setting protected by i_mutex */ @@ -217,13 +245,11 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de if (!(ia_valid & ATTR_MTIME_SET)) attr->ia_mtime = now; if (ia_valid & ATTR_KILL_PRIV) { - attr->ia_valid &= ~ATTR_KILL_PRIV; - ia_valid &= ~ATTR_KILL_PRIV; error = security_inode_need_killpriv(dentry); - if (error > 0) - error = security_inode_killpriv(dentry); - if (error) + if (error < 0) return error; + if (error == 0) + ia_valid = attr->ia_valid &= ~ATTR_KILL_PRIV; } /* |