Date: Fri, 24 Jul 2026 21:07:23 +0000 From: Mark Johnston <markj@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 91e11c8f2b38 - main - procdesc: Disallow pddupfd() of non-passable files Message-ID: <6a63d40b.38396.1656d619@gitrepo.freebsd.org>
index | next in thread | raw e-mail
The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=91e11c8f2b38eb1d1f3a1d57b27378fb2c6ab3c1 commit 91e11c8f2b38eb1d1f3a1d57b27378fb2c6ab3c1 Author: Mark Johnston <markj@FreeBSD.org> AuthorDate: 2026-07-24 20:05:26 +0000 Commit: Mark Johnston <markj@FreeBSD.org> CommitDate: 2026-07-24 20:05:26 +0000 procdesc: Disallow pddupfd() of non-passable files Reported by: Maik Muench of Secfault Security Reviewed by: kib Fixes: 1ad21a652182 ("kern: add pddupfd(2)") Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D58403 --- lib/libsys/pdfork.2 | 6 ++++++ sys/kern/sys_procdesc.c | 10 +++++++--- 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/lib/libsys/pdfork.2 b/lib/libsys/pdfork.2 index 584c87e17e38..1b99157203c1 100644 --- a/lib/libsys/pdfork.2 +++ b/lib/libsys/pdfork.2 @@ -195,6 +195,8 @@ flag set. The .Fa flags argument is reserved and must be zero. +Certain file descriptor types cannot be copied this way, namely +kqueues. .Pp The following system calls also have effects specific to process descriptors: .Pp @@ -350,6 +352,10 @@ The file descriptor is not a valid file descriptor in the specified process. .It Bq Er ENOENT The specified process does not have a file descriptor table. +.It Bq Er EOPNOTSUPP +.Fa remotefd +refers to a file that cannot be duplicated across a process boundary, +such as a kqueue. .El .Sh SEE ALSO .Xr close 2 , diff --git a/sys/kern/sys_procdesc.c b/sys/kern/sys_procdesc.c index 7fc63256bc05..b913c9109f18 100644 --- a/sys/kern/sys_procdesc.c +++ b/sys/kern/sys_procdesc.c @@ -796,9 +796,13 @@ kern_pddupfd(struct thread *td, int pdfd, int fd, int flags) PROC_UNLOCK(p); error = fget_remote(td, p, fd, &fcaps, &fd_flags, &fp); if (error == 0) { - error = finstall_refed(td, fp, &fdr, O_CLOEXEC | - ((fd_flags & FD_RESOLVE_BENEATH) != 0 ? - O_RESOLVE_BENEATH : 0), &fcaps); + if ((fp->f_ops->fo_flags & DFLAG_PASSABLE) == 0) { + error = EOPNOTSUPP; + } else { + error = finstall_refed(td, fp, &fdr, O_CLOEXEC | + ((fd_flags & FD_RESOLVE_BENEATH) != 0 ? + O_RESOLVE_BENEATH : 0), &fcaps); + } if (error != 0) { fdrop(fp, td); filecaps_free(&fcaps);home | help
Want to link to this message? Use this
URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?6a63d40b.38396.1656d619>