The introduction of clone3 syscall accidentally broke CLONE_PIDFD support in traditional clone syscall on compat x86 and those architectures that use do_fork to implement clone syscall.
This bug was found by strace test suite. Link: https://strace.io/logs/strace/2019-07-12 Fixes: 7f192e3cd316 ("fork: add clone3") Bisected-and-tested-by: Anatoly Pugachev <mator...@gmail.com> Signed-off-by: Dmitry V. Levin <l...@altlinux.org> --- arch/x86/ia32/sys_ia32.c | 1 + kernel/fork.c | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/x86/ia32/sys_ia32.c b/arch/x86/ia32/sys_ia32.c index 64a6c952091e..98754baf411a 100644 --- a/arch/x86/ia32/sys_ia32.c +++ b/arch/x86/ia32/sys_ia32.c @@ -239,6 +239,7 @@ COMPAT_SYSCALL_DEFINE5(x86_clone, unsigned long, clone_flags, { struct kernel_clone_args args = { .flags = (clone_flags & ~CSIGNAL), + .pidfd = parent_tidptr, .child_tid = child_tidptr, .parent_tid = parent_tidptr, .exit_signal = (clone_flags & CSIGNAL), diff --git a/kernel/fork.c b/kernel/fork.c index 8f3e2d97d771..2c3cbad807b6 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2417,6 +2417,7 @@ long do_fork(unsigned long clone_flags, { struct kernel_clone_args args = { .flags = (clone_flags & ~CSIGNAL), + .pidfd = parent_tidptr, .child_tid = child_tidptr, .parent_tid = parent_tidptr, .exit_signal = (clone_flags & CSIGNAL), -- ldv
