diff options
author | Stefan Agner <stefan@agner.ch> | 2017-03-14 13:59:28 -0700 |
---|---|---|
committer | Max Krummenacher <max.krummenacher@toradex.com> | 2017-03-15 18:35:51 +0100 |
commit | 39ac0033f2345ce7b5d8ca4439192407dacb2355 (patch) | |
tree | 51dc588baa63d31bc406388885f62c1cae068fa3 /fs/attr.c | |
parent | 13f2767f31803754aa883f298737aff866f04628 (diff) | |
parent | d9e0350d2575a20ee7783427da9bd6b6107eb983 (diff) |
Merge tag 'v4.1.39' into toradex_vf_4.1-nexttoradex_vf_4.1
Linux 4.1.39
Diffstat (limited to 'fs/attr.c')
-rw-r--r-- | fs/attr.c | 35 |
1 files changed, 23 insertions, 12 deletions
diff --git a/fs/attr.c b/fs/attr.c index 6530ced19697..ee697ddc6c2e 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -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 @@ -217,13 +230,11 @@ 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; } /* |