fs/exec.c: make bprm_mm_init() static

[firefly-linux-kernel-4.4.55.git] / fs / open.c

diff --git a/fs/open.c b/fs/open.c
index 59071f55bf7fe97545cc691e5dc845a05cbe8f64..62f907e3bc36aab08513270e6e9d636da96b9664 100644 (file)
--- a/fs/open.c
+++ b/fs/open.c
@@ -61,33 +61,22 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
        return ret;
 }
 
-static long do_sys_truncate(const char __user *pathname, loff_t length)
+long vfs_truncate(struct path *path, loff_t length)
 {
-       struct path path;
        struct inode *inode;
-       int error;
+       long error;
 
-       error = -EINVAL;
-       if (length < 0) /* sorry, but loff_t says... */
-               goto out;
-
-       error = user_path(pathname, &path);
-       if (error)
-               goto out;
-       inode = path.dentry->d_inode;
+       inode = path->dentry->d_inode;
 
        /* For directories it's -EISDIR, for other non-regulars - -EINVAL */
-       error = -EISDIR;
        if (S_ISDIR(inode->i_mode))
-               goto dput_and_out;
-
-       error = -EINVAL;
+               return -EISDIR;
        if (!S_ISREG(inode->i_mode))
-               goto dput_and_out;
+               return -EINVAL;
 
-       error = mnt_want_write(path.mnt);
+       error = mnt_want_write(path->mnt);
        if (error)
-               goto dput_and_out;
+               goto out;
 
        error = inode_permission(inode, MAY_WRITE);
        if (error)
@@ -111,19 +100,40 @@ static long do_sys_truncate(const char __user *pathname, loff_t length)
 
        error = locks_verify_truncate(inode, NULL, length);
        if (!error)
-               error = security_path_truncate(&path);
+               error = security_path_truncate(path);
        if (!error)
-               error = do_truncate(path.dentry, length, 0, NULL);
+               error = do_truncate(path->dentry, length, 0, NULL);
 
 put_write_and_out:
        put_write_access(inode);
 mnt_drop_write_and_out:
-       mnt_drop_write(path.mnt);
-dput_and_out:
-       path_put(&path);
+       mnt_drop_write(path->mnt);
 out:
        return error;
 }
+EXPORT_SYMBOL_GPL(vfs_truncate);
+
+static long do_sys_truncate(const char __user *pathname, loff_t length)
+{
+       unsigned int lookup_flags = LOOKUP_FOLLOW;
+       struct path path;
+       int error;
+
+       if (length < 0) /* sorry, but loff_t says... */
+               return -EINVAL;
+
+retry:
+       error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
+       if (!error) {
+               error = vfs_truncate(&path, length);
+               path_put(&path);
+       }
+       if (retry_estale(error, lookup_flags)) {
+               lookup_flags |= LOOKUP_REVAL;
+               goto retry;
+       }
+       return error;
+}
 
 SYSCALL_DEFINE2(truncate, const char __user *, path, long, length)
 {
@@ -218,7 +228,7 @@ SYSCALL_ALIAS(sys_ftruncate64, SyS_ftruncate64);
 
 int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 {
-       struct inode *inode = file->f_path.dentry->d_inode;
+       struct inode *inode = file_inode(file);
        long ret;
 
        if (offset < 0 || len <= 0)
@@ -306,6 +316,7 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
        struct path path;
        struct inode *inode;
        int res;
+       unsigned int lookup_flags = LOOKUP_FOLLOW;
 
        if (mode & ~S_IRWXO)    /* where's F_OK, X_OK, W_OK, R_OK? */
                return -EINVAL;
@@ -328,8 +339,8 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
        }
 
        old_cred = override_creds(override_cred);
-
-       res = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path);
+retry:
+       res = user_path_at(dfd, filename, lookup_flags, &path);
        if (res)
                goto out;
 
@@ -364,6 +375,10 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
 
 out_path_release:
        path_put(&path);
+       if (retry_estale(res, lookup_flags)) {
+               lookup_flags |= LOOKUP_REVAL;
+               goto retry;
+       }
 out:
        revert_creds(old_cred);
        put_cred(override_cred);
@@ -379,8 +394,9 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
 {
        struct path path;
        int error;
-
-       error = user_path_dir(filename, &path);
+       unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
+retry:
+       error = user_path_at(AT_FDCWD, filename, lookup_flags, &path);
        if (error)
                goto out;
 
@@ -392,6 +408,10 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
 
 dput_and_out:
        path_put(&path);
+       if (retry_estale(error, lookup_flags)) {
+               lookup_flags |= LOOKUP_REVAL;
+               goto retry;
+       }
 out:
        return error;
 }
@@ -406,7 +426,7 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
        if (!f.file)
                goto out;
 
-       inode = f.file->f_path.dentry->d_inode;
+       inode = file_inode(f.file);
 
        error = -ENOTDIR;
        if (!S_ISDIR(inode->i_mode))
@@ -425,8 +445,9 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
 {
        struct path path;
        int error;
-
-       error = user_path_dir(filename, &path);
+       unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
+retry:
+       error = user_path_at(AT_FDCWD, filename, lookup_flags, &path);
        if (error)
                goto out;
 
@@ -435,7 +456,7 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
                goto dput_and_out;
 
        error = -EPERM;
-       if (!capable(CAP_SYS_CHROOT))
+       if (!nsown_capable(CAP_SYS_CHROOT))
                goto dput_and_out;
        error = security_path_chroot(&path);
        if (error)
@@ -445,6 +466,10 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
        error = 0;
 dput_and_out:
        path_put(&path);
+       if (retry_estale(error, lookup_flags)) {
+               lookup_flags |= LOOKUP_REVAL;
+               goto retry;
+       }
 out:
        return error;
 }
@@ -489,11 +514,16 @@ SYSCALL_DEFINE3(fchmodat, int, dfd, const char __user *, filename, umode_t, mode
 {
        struct path path;
        int error;
-
-       error = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path);
+       unsigned int lookup_flags = LOOKUP_FOLLOW;
+retry:
+       error = user_path_at(dfd, filename, lookup_flags, &path);
        if (!error) {
                error = chmod_common(&path, mode);
                path_put(&path);
+               if (retry_estale(error, lookup_flags)) {
+                       lookup_flags |= LOOKUP_REVAL;
+                       goto retry;
+               }
        }
        return error;
 }
@@ -552,6 +582,7 @@ SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user,
        lookup_flags = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
        if (flag & AT_EMPTY_PATH)
                lookup_flags |= LOOKUP_EMPTY;
+retry:
        error = user_path_at(dfd, filename, lookup_flags, &path);
        if (error)
                goto out;
@@ -562,6 +593,10 @@ SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user,
        mnt_drop_write(path.mnt);
 out_release:
        path_put(&path);
+       if (retry_estale(error, lookup_flags)) {
+               lookup_flags |= LOOKUP_REVAL;
+               goto retry;
+       }
 out:
        return error;
 }
@@ -654,7 +689,7 @@ static int do_dentry_open(struct file *f,
                f->f_mode = FMODE_PATH;
 
        path_get(&f->f_path);
-       inode = f->f_path.dentry->d_inode;
+       inode = file_inode(f);
        if (f->f_mode & FMODE_WRITE) {
                error = __get_file_write_access(inode, f->f_path.mnt);
                if (error)
@@ -664,7 +699,6 @@ static int do_dentry_open(struct file *f,
        }
 
        f->f_mapping = inode->i_mapping;
-       f->f_pos = 0;
        file_sb_list_add(f, inode->i_sb);
 
        if (unlikely(f->f_mode & FMODE_PATH)) {
@@ -775,23 +809,22 @@ struct file *dentry_open(const struct path *path, int flags,
        /* We must always pass in a valid mount pointer. */
        BUG_ON(!path->mnt);
 
-       error = -ENFILE;
        f = get_empty_filp();
-       if (f == NULL)
-               return ERR_PTR(error);
-
-       f->f_flags = flags;
-       f->f_path = *path;
-       error = do_dentry_open(f, NULL, cred);
-       if (!error) {
-               error = open_check_o_direct(f);
-               if (error) {
-                       fput(f);
+       if (!IS_ERR(f)) {
+               f->f_flags = flags;
+               f->f_path = *path;
+               error = do_dentry_open(f, NULL, cred);
+               if (!error) {
+                       /* from now on we need fput() to dispose of f */
+                       error = open_check_o_direct(f);
+                       if (error) {
+                               fput(f);
+                               f = ERR_PTR(error);
+                       }
+               } else { 
+                       put_filp(f);
                        f = ERR_PTR(error);
                }
-       } else { 
-               put_filp(f);
-               f = ERR_PTR(error);
        }
        return f;
 }