PR/60135 CVS commit: src/sys/kern

["YAMAMOTO Takashi" <yamt%netbsd.org@localhost>]

The following reply was made to PR kern/60135; it has been noted by GNATS.

From: "YAMAMOTO Takashi" <yamt%netbsd.org@localhost>
To: gnats-bugs%gnats.NetBSD.org@localhost
Cc: 
Subject: PR/60135 CVS commit: src/sys/kern
Date: Fri, 27 Mar 2026 23:43:13 +0000

 Module Name:	src
 Committed By:	yamt
 Date:		Fri Mar 27 23:43:13 UTC 2026
 
 Modified Files:
 	src/sys/kern: vfs_init.c
 
 Log Message:
 vfs_attach: reject file system with non-unique fstype
 
 while currently our fstype values are still unique, given the poor
 hash function used by makefstype [1], it isn't too unlikely for a future
 or out-of-tree file system to have a conflicting value. it's safer
 to reject it explicitly. note that, we can't lightly change the hash
 function because it's exposed as a part of nfs file handles.
 
 [1] for example, makefstype("qa") == makefstype("uq") == 0x1a5.
 
 the current list of fstype values used by the in-tree file systems:
 
     0000064b zfs
     000006a6 udf
     0000070b nfs
     0000072b lfs
     0000073b mfs
     0000076b hfs
     0000078b ffs
     000007bb efs
     000007fb afs
     00001a64 umap
     00001d0c null
     00001d2b ntfs
     00001f1b v7fs
     00001fc1 coda
     000069ab tmpfs
     000069c2 union
     00006acb puffs
     00006b7b ptyfs
     00006f8b smbfs
     0000736b nilfs
     0000764f msdos
     000078ff fdesc
     0001a0ab rumpfs
     0001ae1b procfs
     0001d28b kernfs
     0001e5c8 cd9660
     0001eb1b autofs
     0001f3cb ext2fs
     0001fd1b adosfs
     0006bd4b sysvbfs
     000756bd overlay
     001eda9d filecore
 
 related to PR/60135
 https://gnats.netbsd.org/60135
 
 
 To generate a diff of this commit:
 cvs rdiff -u -r1.67 -r1.68 src/sys/kern/vfs_init.c
 
 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.