Re: git: e59991206b14 - main - fts(3): be less strict when automount does its job under us walking autofs mount

On 2/26/25 07:36, Ronald Klop wrote:
> 
> *Van:* Konstantin Belousov <kib@FreeBSD.org>
> *Datum:* 25 februari 2025 08:20
> *Aan:* src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev- 
> commits-src-main@FreeBSD.org
> *Onderwerp:* git: e59991206b14 - main - fts(3): be less strict when 
> automount does its job under us walking autofs mount
> 
>     The branch main has been updated by kib:
> 
>     URL: https://cgit.FreeBSD.org/src/commit/?
>     id=e59991206b1463b7e85cc8aafde7f1dc03fcedcf <https://
>     cgit.FreeBSD.org/src/commit/?
>     id=e59991206b1463b7e85cc8aafde7f1dc03fcedcf>
> 
>     commit e59991206b1463b7e85cc8aafde7f1dc03fcedcf
>     Author:     Konstantin Belousov
>     AuthorDate: 2025-02-21 13:07:43 +0000
>     Commit:     Konstantin Belousov
>     CommitDate: 2025-02-25 07:09:29 +0000
> 
>          fts(3): be less strict when automount does its job under us
>     walking autofs mount
> 
>          Namely, allow the file id change if the resulting file belongs to
>          automounted filesystem.  If it is, remember the updated id.
> 
>          This allows the ids from the automounted volumes to change without
>          restrictions, might be a further refinement would be to only
>     allow such
>          inconsistency once.
> 
>          PR:     284914
>          Reported and tested by: Lexi Winter
>          Sponsored by:   The FreeBSD Foundation
>          MFC after:      1 week
>          Differential revision: https://reviews.freebsd.org/D49094
>     <https://reviews.freebsd.org/D49094>
>     ---
>       lib/libc/gen/fts.c | 13 ++++++++++---
>       1 file changed, 10 insertions(+), 3 deletions(-)
> 
>     diff --git a/lib/libc/gen/fts.c b/lib/libc/gen/fts.c
>     index 770a7b2cc322..bd193c7c6cfc 100644
>     --- a/lib/libc/gen/fts.c
>     +++ b/lib/libc/gen/fts.c
>     @@ -1132,6 +1132,7 @@ fts_safe_changedir(FTS *sp, FTSENT *p, int fd,
>     char *path)
>       {
>          int ret, oerrno, newfd;
>          struct stat sb;
>     +   struct statfs sf;
> 
>          newfd = fd;
>          if (ISSET(FTS_NOCHDIR))
>     @@ -1144,9 +1145,15 @@ fts_safe_changedir(FTS *sp, FTSENT *p, int
>     fd, char *path)
>              goto bail;
>          }
>          if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) {
>     -       errno = ENOENT;     /* disinformation */
>     -       ret = -1;
>     -       goto bail;
>     +       if (_fstatfs(newfd, &sf) != 0 ||
>     +           (sf.f_flags & MNT_AUTOMOUNTED) == 0) {
>     +           errno = ENOENT;     /* disinformation */
>     +           ret = -1;
>     +           goto bail;
>     +       }
>     +       /* autofs might did the mount under us, accept. */
>     +       p->fts_dev = sb.st_dev;
>     +       p->fts_ino == sb.st_ino;
>          }
>          ret = fchdir(newfd);
>       bail:
> 
>     ------------------------------------------------------------------------
> 
> 
> 
>     /* autofs might did the mount under us, accept. */
> 
> 
> I’m not native English so forgive me my question. But what does this 
> comment mean?
> 

It might have triggered an autofs mount while we're running, so we just 
accept the otherwise suspicious looking change.