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@@ -1444,69 +1444,52 @@ int may_open(struct path *path, int acc_mode, int flag)
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if (error)
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return error;
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- error = ima_path_check(path, acc_mode ?
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- acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC) :
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- ACC_MODE(flag) & (MAY_READ | MAY_WRITE),
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- IMA_COUNT_UPDATE);
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-
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- if (error)
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- return error;
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/*
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* An append-only file must be opened in append mode for writing.
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*/
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if (IS_APPEND(inode)) {
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- error = -EPERM;
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if ((flag & FMODE_WRITE) && !(flag & O_APPEND))
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- goto err_out;
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+ return -EPERM;
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if (flag & O_TRUNC)
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- goto err_out;
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+ return -EPERM;
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}
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/* O_NOATIME can only be set by the owner or superuser */
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- if (flag & O_NOATIME)
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- if (!is_owner_or_cap(inode)) {
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- error = -EPERM;
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- goto err_out;
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- }
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+ if (flag & O_NOATIME && !is_owner_or_cap(inode))
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+ return -EPERM;
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/*
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* Ensure there are no outstanding leases on the file.
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*/
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error = break_lease(inode, flag);
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if (error)
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- goto err_out;
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-
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- if (flag & O_TRUNC) {
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- error = get_write_access(inode);
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- if (error)
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- goto err_out;
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-
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- /*
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- * Refuse to truncate files with mandatory locks held on them.
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- */
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- error = locks_verify_locked(inode);
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- if (!error)
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- error = security_path_truncate(path, 0,
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- ATTR_MTIME|ATTR_CTIME|ATTR_OPEN);
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- if (!error) {
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- vfs_dq_init(inode);
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+ return error;
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- error = do_truncate(dentry, 0,
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- ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
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- NULL);
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- }
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- put_write_access(inode);
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- if (error)
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- goto err_out;
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- } else
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- if (flag & FMODE_WRITE)
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- vfs_dq_init(inode);
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+ return ima_path_check(path, acc_mode ?
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+ acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC) :
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+ ACC_MODE(flag) & (MAY_READ | MAY_WRITE),
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+ IMA_COUNT_UPDATE);
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+}
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- return 0;
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-err_out:
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- ima_counts_put(path, acc_mode ?
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- acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC) :
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- ACC_MODE(flag) & (MAY_READ | MAY_WRITE));
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+static int handle_truncate(struct path *path)
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+{
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+ struct inode *inode = path->dentry->d_inode;
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+ int error = get_write_access(inode);
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+ if (error)
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+ return error;
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+ /*
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+ * Refuse to truncate files with mandatory locks held on them.
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+ */
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+ error = locks_verify_locked(inode);
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+ if (!error)
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+ error = security_path_truncate(path, 0,
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+ ATTR_MTIME|ATTR_CTIME|ATTR_OPEN);
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+ if (!error) {
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+ error = do_truncate(path->dentry, 0,
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+ ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
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+ NULL);
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+ }
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+ put_write_access(inode);
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return error;
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}
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@@ -1561,7 +1544,7 @@ static inline int open_to_namei_flags(int flag)
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return flag;
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}
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-static int open_will_write_to_fs(int flag, struct inode *inode)
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+static int open_will_truncate(int flag, struct inode *inode)
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{
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/*
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* We'll never write to the fs underlying
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@@ -1586,7 +1569,7 @@ struct file *do_filp_open(int dfd, const char *pathname,
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struct path path, save;
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struct dentry *dir;
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int count = 0;
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- int will_write;
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+ int will_truncate;
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int flag = open_to_namei_flags(open_flag);
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/*
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@@ -1752,28 +1735,48 @@ ok:
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* be avoided. Taking this mnt write here
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* ensures that (2) can not occur.
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*/
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- will_write = open_will_write_to_fs(flag, nd.path.dentry->d_inode);
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- if (will_write) {
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+ will_truncate = open_will_truncate(flag, nd.path.dentry->d_inode);
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+ if (will_truncate) {
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error = mnt_want_write(nd.path.mnt);
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if (error)
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goto exit;
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}
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error = may_open(&nd.path, acc_mode, flag);
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if (error) {
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- if (will_write)
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+ if (will_truncate)
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mnt_drop_write(nd.path.mnt);
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goto exit;
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}
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filp = nameidata_to_filp(&nd, open_flag);
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- if (IS_ERR(filp))
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+ if (IS_ERR(filp)) {
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ima_counts_put(&nd.path,
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acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC));
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+ if (will_truncate)
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+ mnt_drop_write(nd.path.mnt);
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+ if (nd.root.mnt)
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+ path_put(&nd.root);
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+ return filp;
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+ }
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+
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+ if (acc_mode & MAY_WRITE)
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+ vfs_dq_init(nd.path.dentry->d_inode);
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+
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+ if (will_truncate) {
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+ error = handle_truncate(&nd.path);
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+ if (error) {
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+ mnt_drop_write(nd.path.mnt);
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+ fput(filp);
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+ if (nd.root.mnt)
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+ path_put(&nd.root);
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+ return ERR_PTR(error);
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+ }
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+ }
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/*
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* It is now safe to drop the mnt write
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* because the filp has had a write taken
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* on its behalf.
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*/
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- if (will_write)
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+ if (will_truncate)
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mnt_drop_write(nd.path.mnt);
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if (nd.root.mnt)
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path_put(&nd.root);
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