Hey team systemtap,

I have fixed some formatting issues, here is the new patch for it.
Could you please help review it?

On Fri, Dec 3, 2021 at 2:46 PM Di Chen <dichen@redhat.com> wrote:

>
> From d2afae5de4c5135046606420787d539865b1832c Mon Sep 17 00:00:00 2001
> From: Di Chen <dichen@redhat.com>
> Date: Fri, 5 Nov 2021 22:34:37 +0800
> Subject: [PATCH] Add support for new syscall memfd_secret
>
> Linux 5.14 added the memfd_secret syscall, adding tapset support.
>
> memfd_secret() was disabled by default and a command-line option
> was added to enable it at boot time.
>
> $ cat /proc/cmdline
> [...] secretmem.enable=y
>
> https://sourceware.org/bugzilla/show_bug.cgi?id=28418
> https://lwn.net/Articles/865256/
>
> Signed-off-by: Di Chen <dichen@redhat.com>
> ---
>  runtime/linux/compat_unistd.h              |   4 +
>  tapset/linux/aux_syscalls.stp              |   3 +
>  tapset/linux/sysc_memfd_secret.stp         | 102 +++++++++++++++++++++
>  testsuite/systemtap.syscall/memfd_secret.c |  22 +++++
>  4 files changed, 131 insertions(+)
>  create mode 100644 tapset/linux/sysc_memfd_secret.stp
>  create mode 100644 testsuite/systemtap.syscall/memfd_secret.c
>
> diff --git a/runtime/linux/compat_unistd.h b/runtime/linux/compat_unistd.h
> index 5a932cc17..5e73950b9 100644
> --- a/runtime/linux/compat_unistd.h
> +++ b/runtime/linux/compat_unistd.h
> @@ -920,6 +920,9 @@
>  #ifndef __NR_ia32_memfd_create
>  #define __NR_ia32_memfd_create 356
>  #endif
> +#ifndef __NR_ia32_memfd_secret
> +#define __NR_ia32_memfd_secret 447
> +#endif
>  #ifndef __NR_ia32_migrate_pages
>  #define __NR_ia32_migrate_pages 294
>  #endif
> @@ -1999,6 +2002,7 @@
>  #define __NR_compat_mbind __NR_mbind
>  #define __NR_compat_membarrier __NR_membarrier
>  #define __NR_compat_memfd_create __NR_memfd_create
> +#define __NR_compat_memfd_secret   __NR_memfd_secret
>  #define __NR_compat_migrate_pages __NR_migrate_pages
>  #define __NR_compat_mincore __NR_mincore
>  #define __NR_compat_mkdir __NR_mkdir
> diff --git a/tapset/linux/aux_syscalls.stp b/tapset/linux/aux_syscalls.stp
> index 3313fb441..4a4bac4df 100644
> --- a/tapset/linux/aux_syscalls.stp
> +++ b/tapset/linux/aux_syscalls.stp
> @@ -1703,6 +1703,9 @@ static const _stp_val_array _stp_mfd_flags_list[] = {
>  #endif
>  #ifdef MFD_ALLOW_SEALING
>          V(MFD_ALLOW_SEALING),
> +#endif
> +#ifdef O_CLOEXEC
> +        V(O_CLOEXEC),
>  #endif
>          {0, NULL}
>  };
> diff --git a/tapset/linux/sysc_memfd_secret.stp
> b/tapset/linux/sysc_memfd_secret.stp
> new file mode 100644
> index 000000000..aa9b125ec
> --- /dev/null
> +++ b/tapset/linux/sysc_memfd_secret.stp
> @@ -0,0 +1,102 @@
> +# memfd_secret _____________________________________________________
> +# long sys_memfd_secret (unsigned int flags)
> +
> +/* kernel 5.14+ */
> +@define _SYSCALL_MEMFD_SECRET_NAME
> +%(
> + name = "memfd_secret"
> +%)
> +
> +@define _SYSCALL_MEMFD_SECRET_ARGSTR
> +%(
> + argstr = sprintf("%s", flags_str)
> +%)
> +
> +@define _SYSCALL_MEMFD_SECRET_REGARGS
> +%(
> + flags = uint_arg(1)
> + flags_str = _mfd_flags_str(uint_arg(1))
> +%)
> +
> +@define _SYSCALL_MEMFD_SECRET_REGARGS_STORE
> +%(
> + if (@probewrite(flags))
> +  set_uint_arg(1, flags)
> +%)
> +
> +probe syscall.memfd_secret = dw_syscall.memfd_secret !,
> nd_syscall.memfd_secret ? {}
> +probe syscall.memfd_secret.return = dw_syscall.memfd_secret.return !,
> nd_syscall.memfd_secret.return ? {}
> +
> +# dw_memfd_secret _____________________________________________________
> +
> +probe dw_syscall.memfd_secret = kernel.function("sys_memfd_secret").call ?
> +{
> + @_SYSCALL_MEMFD_SECRET_NAME
> + flags = $flags
> + flags_str = _mfd_flags_str($flags)
> + @_SYSCALL_MEMFD_SECRET_ARGSTR
> +}
> +probe dw_syscall.memfd_secret.return =
> kernel.function("sys_memfd_secret").return ?
> +{
> + @_SYSCALL_MEMFD_SECRET_NAME
> + @SYSC_RETVALSTR($return)
> +}
> +
> +# nd_memfd_secret _____________________________________________________
> +
> +probe nd_syscall.memfd_secret = nd1_syscall.memfd_secret!,
> nd2_syscall.memfd_secret!, tp_syscall.memfd_secret
> +  { }
> +
> +probe nd1_syscall.memfd_secret = kprobe.function("sys_memfd_secret") ?
> +{
> + @_SYSCALL_MEMFD_SECRET_NAME
> + asmlinkage()
> + @_SYSCALL_MEMFD_SECRET_REGARGS
> + @_SYSCALL_MEMFD_SECRET_ARGSTR
> +}
> +
> +probe nd2_syscall.memfd_secret = kprobe.function(@arch_syscall_prefix
> "sys_memfd_secret") ?
> +{
> + __set_syscall_pt_regs(pointer_arg(1))
> + @_SYSCALL_MEMFD_SECRET_NAME
> + @_SYSCALL_MEMFD_SECRET_REGARGS
> + @_SYSCALL_MEMFD_SECRET_ARGSTR
> +},
> +{
> +        %( @_IS_SREG_KERNEL %? @_SYSCALL_MEMFD_SECRET_REGARGS_STORE %)
> +}
> +
> +probe tp_syscall.memfd_secret = kernel.trace("sys_enter")
> +{
> + __set_syscall_pt_regs($regs)
> + @__syscall_compat_gate(@const("__NR_memfd_secret"),
> @const("__NR_compat_memfd_secret"))
> + @_SYSCALL_MEMFD_SECRET_NAME
> + @_SYSCALL_MEMFD_SECRET_REGARGS
> + @_SYSCALL_MEMFD_SECRET_ARGSTR
> +},
> +{
> +        %( @_IS_SREG_KERNEL %? @_SYSCALL_MEMFD_SECRET_REGARGS_STORE %)
> +}
> +
> +probe nd_syscall.memfd_secret.return = nd1_syscall.memfd_secret.return!,
> nd2_syscall.memfd_secret.return!, tp_syscall.memfd_secret.return
> +  { }
> +
> +probe nd1_syscall.memfd_secret.return =
> kprobe.function("sys_memfd_secret").return ?
> +{
> + @_SYSCALL_MEMFD_SECRET_NAME
> + @SYSC_RETVALSTR(returnval())
> +}
> +
> +probe nd2_syscall.memfd_secret.return =
> kprobe.function(@arch_syscall_prefix "sys_memfd_secret").return ?
> +{
> + @_SYSCALL_MEMFD_SECRET_NAME
> + @SYSC_RETVALSTR(returnval())
> +}
> +
> +probe tp_syscall.memfd_secret.return = kernel.trace("sys_exit")
> +{
> + __set_syscall_pt_regs($regs)
> + @__syscall_compat_gate(@const("__NR_memfd_secret"),
> @const("__NR_compat_memfd_secret"))
> + @_SYSCALL_MEMFD_SECRET_NAME
> + @SYSC_RETVALSTR($ret)
> +}
> diff --git a/testsuite/systemtap.syscall/memfd_secret.c
> b/testsuite/systemtap.syscall/memfd_secret.c
> new file mode 100644
> index 000000000..9a467db86
> --- /dev/null
> +++ b/testsuite/systemtap.syscall/memfd_secret.c
> @@ -0,0 +1,22 @@
> +/* COVERAGE: memfd_secret */
> +
> +/*
> + * Glibc doesn't support memfd_secret yet, so we have to use syscall(2)
> + */
> +#define _GNU_SOURCE
> +#include <sys/syscall.h>
> +#include <unistd.h>
> +#include <fcntl.h>
> +
> +#ifdef __NR_memfd_secret
> +
> +int main()
> +{
> +    int fd;
> +    fd = syscall(__NR_memfd_secret, O_CLOEXEC);
> +    //staptest// memfd_secret (O_CLOEXEC) = NNNN
> +
> +    close(fd);
> +}
> +
> +#endif
> --
> 2.33.1
>
>
>