On 2023/1/11 2:01, Alexey Dobriyan wrote:
On Tue, Jan 10, 2023 at 11:21:12PM +0800, Chao Yu wrote:
__proc_create() has limited dirent's max name length with 255, let's
add this limitation in proc_lookup_de(), so that it can return
-ENAMETOOLONG correctly instead of -ENOENT when stating a file which
has out-of-range name length.
Both returns are correct and this is trading one errno for another.
Oh, but it looks ENOENT is a little bit ambiguity, it may indicate file name
length is valid for procfs, but the entry is not exist.
This change is trying to make lookup logic keeping align w/ most other
filesystems' behavior. Also it can avoid running into unneeded lookup logic
in proc_lookup_de() for such ENAMETOOLONG case.
How do you think? :)
Thanks,
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -246,6 +246,9 @@ struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry,
{
struct inode *inode;
+ if (dentry->d_name.len > PROC_NAME_LEN)
+ return ERR_PTR(-ENAMETOOLONG);
