diff options
| author | Christian Brauner <brauner@kernel.org> | 2025-06-24 10:29:05 +0200 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2025-06-24 13:00:09 +0200 |
| commit | 774adcb55f159167fe0dfd343174fdedba3ae2f4 (patch) | |
| tree | dca3c5ab93207599db15fe4d1b06415d2cef030e | |
| parent | cc678bf7aa9e2e6c2356fd7f955513c1bd7d4c97 (diff) | |
fhandle: hoist copy_from_user() above get_path_from_fd()
In follow-up patches we need access to @file_handle->handle_type
before we start caring about get_path_from_fd().
Link: https://lore.kernel.org/20250624-work-pidfs-fhandle-v2-2-d02a04858fe3@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
| -rw-r--r-- | fs/fhandle.c | 35 |
1 files changed, 14 insertions, 21 deletions
diff --git a/fs/fhandle.c b/fs/fhandle.c index 66ff60591d17..73f56f8e7d5d 100644 --- a/fs/fhandle.c +++ b/fs/fhandle.c @@ -323,13 +323,24 @@ static int handle_to_path(int mountdirfd, struct file_handle __user *ufh, { int retval = 0; struct file_handle f_handle; - struct file_handle *handle = NULL; + struct file_handle *handle __free(kfree) = NULL; struct handle_to_path_ctx ctx = {}; const struct export_operations *eops; + if (copy_from_user(&f_handle, ufh, sizeof(struct file_handle))) + return -EFAULT; + + if ((f_handle.handle_bytes > MAX_HANDLE_SZ) || + (f_handle.handle_bytes == 0)) + return -EINVAL; + + if (f_handle.handle_type < 0 || + FILEID_USER_FLAGS(f_handle.handle_type) & ~FILEID_VALID_USER_FLAGS) + return -EINVAL; + retval = get_path_from_fd(mountdirfd, &ctx.root); if (retval) - goto out_err; + return retval; eops = ctx.root.mnt->mnt_sb->s_export_op; if (eops && eops->permission) @@ -339,21 +350,6 @@ static int handle_to_path(int mountdirfd, struct file_handle __user *ufh, if (retval) goto out_path; - if (copy_from_user(&f_handle, ufh, sizeof(struct file_handle))) { - retval = -EFAULT; - goto out_path; - } - if ((f_handle.handle_bytes > MAX_HANDLE_SZ) || - (f_handle.handle_bytes == 0)) { - retval = -EINVAL; - goto out_path; - } - if (f_handle.handle_type < 0 || - FILEID_USER_FLAGS(f_handle.handle_type) & ~FILEID_VALID_USER_FLAGS) { - retval = -EINVAL; - goto out_path; - } - handle = kmalloc(struct_size(handle, f_handle, f_handle.handle_bytes), GFP_KERNEL); if (!handle) { @@ -366,7 +362,7 @@ static int handle_to_path(int mountdirfd, struct file_handle __user *ufh, &ufh->f_handle, f_handle.handle_bytes)) { retval = -EFAULT; - goto out_handle; + goto out_path; } /* @@ -384,11 +380,8 @@ static int handle_to_path(int mountdirfd, struct file_handle __user *ufh, handle->handle_type &= ~FILEID_USER_FLAGS_MASK; retval = do_handle_to_path(handle, path, &ctx); -out_handle: - kfree(handle); out_path: path_put(&ctx.root); -out_err: return retval; } |