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759bfee658
Currently notify_change calls vfs_dq_transfer directly. This means we tie the quota code into the VFS. Get rid of that and make the filesystem responsible for the transfer. Most filesystems already do this, only ufs and udf need the code added, and for jfs it needs to be enabled unconditionally instead of only when ACLs are enabled. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
228 lines
5.8 KiB
C
228 lines
5.8 KiB
C
/*
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* linux/fs/attr.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* changes by Thomas Schoebel-Theuer
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*/
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#include <linux/module.h>
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#include <linux/time.h>
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#include <linux/mm.h>
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#include <linux/string.h>
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#include <linux/capability.h>
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#include <linux/fsnotify.h>
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#include <linux/fcntl.h>
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#include <linux/security.h>
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/* Taken over from the old code... */
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/* POSIX UID/GID verification for setting inode attributes. */
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int inode_change_ok(const struct inode *inode, struct iattr *attr)
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{
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int retval = -EPERM;
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unsigned int ia_valid = attr->ia_valid;
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/* If force is set do it anyway. */
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if (ia_valid & ATTR_FORCE)
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goto fine;
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/* Make sure a caller can chown. */
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if ((ia_valid & ATTR_UID) &&
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(current_fsuid() != inode->i_uid ||
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attr->ia_uid != inode->i_uid) && !capable(CAP_CHOWN))
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goto error;
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/* Make sure caller can chgrp. */
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if ((ia_valid & ATTR_GID) &&
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(current_fsuid() != inode->i_uid ||
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(!in_group_p(attr->ia_gid) && attr->ia_gid != inode->i_gid)) &&
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!capable(CAP_CHOWN))
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goto error;
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/* Make sure a caller can chmod. */
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if (ia_valid & ATTR_MODE) {
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if (!is_owner_or_cap(inode))
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goto error;
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/* Also check the setgid bit! */
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if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
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inode->i_gid) && !capable(CAP_FSETID))
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attr->ia_mode &= ~S_ISGID;
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}
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/* Check for setting the inode time. */
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if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) {
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if (!is_owner_or_cap(inode))
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goto error;
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}
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fine:
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retval = 0;
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error:
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return retval;
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}
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EXPORT_SYMBOL(inode_change_ok);
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/**
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* inode_newsize_ok - may this inode be truncated to a given size
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* @inode: the inode to be truncated
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* @offset: the new size to assign to the inode
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* @Returns: 0 on success, -ve errno on failure
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*
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* inode_newsize_ok will check filesystem limits and ulimits to check that the
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* new inode size is within limits. inode_newsize_ok will also send SIGXFSZ
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* when necessary. Caller must not proceed with inode size change if failure is
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* returned. @inode must be a file (not directory), with appropriate
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* permissions to allow truncate (inode_newsize_ok does NOT check these
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* conditions).
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*
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* inode_newsize_ok must be called with i_mutex held.
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*/
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int inode_newsize_ok(const struct inode *inode, loff_t offset)
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{
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if (inode->i_size < offset) {
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unsigned long limit;
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limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
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if (limit != RLIM_INFINITY && offset > limit)
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goto out_sig;
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if (offset > inode->i_sb->s_maxbytes)
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goto out_big;
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} else {
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/*
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* truncation of in-use swapfiles is disallowed - it would
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* cause subsequent swapout to scribble on the now-freed
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* blocks.
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*/
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if (IS_SWAPFILE(inode))
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return -ETXTBSY;
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}
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return 0;
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out_sig:
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send_sig(SIGXFSZ, current, 0);
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out_big:
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return -EFBIG;
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}
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EXPORT_SYMBOL(inode_newsize_ok);
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int inode_setattr(struct inode * inode, struct iattr * attr)
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{
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unsigned int ia_valid = attr->ia_valid;
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if (ia_valid & ATTR_SIZE &&
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attr->ia_size != i_size_read(inode)) {
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int error = vmtruncate(inode, attr->ia_size);
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if (error)
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return error;
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}
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if (ia_valid & ATTR_UID)
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inode->i_uid = attr->ia_uid;
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if (ia_valid & ATTR_GID)
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inode->i_gid = attr->ia_gid;
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if (ia_valid & ATTR_ATIME)
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inode->i_atime = timespec_trunc(attr->ia_atime,
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inode->i_sb->s_time_gran);
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if (ia_valid & ATTR_MTIME)
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inode->i_mtime = timespec_trunc(attr->ia_mtime,
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inode->i_sb->s_time_gran);
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if (ia_valid & ATTR_CTIME)
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inode->i_ctime = timespec_trunc(attr->ia_ctime,
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inode->i_sb->s_time_gran);
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if (ia_valid & ATTR_MODE) {
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umode_t mode = attr->ia_mode;
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if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
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mode &= ~S_ISGID;
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inode->i_mode = mode;
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}
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mark_inode_dirty(inode);
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return 0;
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}
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EXPORT_SYMBOL(inode_setattr);
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int notify_change(struct dentry * dentry, struct iattr * attr)
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{
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struct inode *inode = dentry->d_inode;
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mode_t mode = inode->i_mode;
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int error;
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struct timespec now;
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unsigned int ia_valid = attr->ia_valid;
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if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_TIMES_SET)) {
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if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
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return -EPERM;
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}
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now = current_fs_time(inode->i_sb);
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attr->ia_ctime = now;
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if (!(ia_valid & ATTR_ATIME_SET))
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attr->ia_atime = now;
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if (!(ia_valid & ATTR_MTIME_SET))
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attr->ia_mtime = now;
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if (ia_valid & ATTR_KILL_PRIV) {
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attr->ia_valid &= ~ATTR_KILL_PRIV;
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ia_valid &= ~ATTR_KILL_PRIV;
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error = security_inode_need_killpriv(dentry);
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if (error > 0)
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error = security_inode_killpriv(dentry);
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if (error)
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return error;
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}
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/*
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* We now pass ATTR_KILL_S*ID to the lower level setattr function so
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* that the function has the ability to reinterpret a mode change
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* that's due to these bits. This adds an implicit restriction that
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* no function will ever call notify_change with both ATTR_MODE and
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* ATTR_KILL_S*ID set.
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*/
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if ((ia_valid & (ATTR_KILL_SUID|ATTR_KILL_SGID)) &&
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(ia_valid & ATTR_MODE))
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BUG();
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if (ia_valid & ATTR_KILL_SUID) {
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if (mode & S_ISUID) {
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ia_valid = attr->ia_valid |= ATTR_MODE;
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attr->ia_mode = (inode->i_mode & ~S_ISUID);
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}
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}
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if (ia_valid & ATTR_KILL_SGID) {
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if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
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if (!(ia_valid & ATTR_MODE)) {
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ia_valid = attr->ia_valid |= ATTR_MODE;
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attr->ia_mode = inode->i_mode;
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}
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attr->ia_mode &= ~S_ISGID;
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}
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}
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if (!(attr->ia_valid & ~(ATTR_KILL_SUID | ATTR_KILL_SGID)))
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return 0;
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error = security_inode_setattr(dentry, attr);
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if (error)
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return error;
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if (ia_valid & ATTR_SIZE)
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down_write(&dentry->d_inode->i_alloc_sem);
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if (inode->i_op && inode->i_op->setattr) {
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error = inode->i_op->setattr(dentry, attr);
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} else {
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error = inode_change_ok(inode, attr);
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if (!error)
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error = inode_setattr(inode, attr);
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}
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if (ia_valid & ATTR_SIZE)
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up_write(&dentry->d_inode->i_alloc_sem);
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if (!error)
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fsnotify_change(dentry, ia_valid);
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return error;
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}
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EXPORT_SYMBOL(notify_change);
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