linux-user: Add AT_EXECFN and AT_EXECFD auxval
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Message ID 20200221202857.126170-1-yuanzi@google.com
State New
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  • linux-user: Add AT_EXECFN and AT_EXECFD auxval
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Commit Message

Lirong Yuan Feb. 21, 2020, 8:28 p.m. UTC
This change adds the support for AT_EXECFN and AT_EXECFD auxval.

Signed-off-by: Lirong Yuan <yuanzi@google.com>
---
 linux-user/elfload.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

Comments

Lirong Yuan Feb. 29, 2020, 12:41 a.m. UTC | #1
On Fri, Feb 21, 2020 at 12:29 PM Lirong Yuan <yuanzi@google.com> wrote:
>
> This change adds the support for AT_EXECFN and AT_EXECFD auxval.
>
> Signed-off-by: Lirong Yuan <yuanzi@google.com>
> ---
>  linux-user/elfload.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/linux-user/elfload.c b/linux-user/elfload.c
> index f3080a1635..7e0f3042f1 100644
> --- a/linux-user/elfload.c
> +++ b/linux-user/elfload.c
> @@ -1568,7 +1568,7 @@ struct exec
>                                   ~(abi_ulong)(TARGET_ELF_EXEC_PAGESIZE-1))
>  #define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1))
>
> -#define DLINFO_ITEMS 15
> +#define DLINFO_ITEMS 17
>
>  static inline void memcpy_fromfs(void * to, const void * from, unsigned long n)
>  {
> @@ -1888,11 +1888,14 @@ static abi_ulong loader_build_fdpic_loadmap(struct image_info *info, abi_ulong s
>      return sp;
>  }
>
> -static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
> +static abi_ulong create_elf_tables(struct linux_binprm *bprm,
>                                     struct elfhdr *exec,
>                                     struct image_info *info,
>                                     struct image_info *interp_info)
>  {
> +    abi_ulong p = bprm->p;
> +    int argc = bprm->argc;
> +    int envc = bprm->envc;
>      abi_ulong sp;
>      abi_ulong u_argc, u_argv, u_envp, u_auxv;
>      int size;
> @@ -2032,6 +2035,8 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
>      NEW_AUX_ENT(AT_CLKTCK, (abi_ulong) sysconf(_SC_CLK_TCK));
>      NEW_AUX_ENT(AT_RANDOM, (abi_ulong) u_rand_bytes);
>      NEW_AUX_ENT(AT_SECURE, (abi_ulong) qemu_getauxval(AT_SECURE));
> +    NEW_AUX_ENT(AT_EXECFN, info->file_string);
> +    NEW_AUX_ENT(AT_EXECFD, bprm->fd);
>
>  #ifdef ELF_HWCAP2
>      NEW_AUX_ENT(AT_HWCAP2, (abi_ulong) ELF_HWCAP2);
> @@ -2870,8 +2875,8 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
>  #endif
>      }
>
> -    bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &elf_ex,
> -                                info, (elf_interpreter ? &interp_info : NULL));
> +    bprm->p = create_elf_tables(bprm, &elf_ex, info,
> +                                (elf_interpreter ? &interp_info : NULL));
>      info->start_stack = bprm->p;
>
>      /* If we have an interpreter, set that as the program's entry point.
> --
> 2.25.0.265.gbab2e86ba0-goog
>

Friendly ping~

Link to the page for the patch on patchwork:
http://patchwork.ozlabs.org/patch/1242331/
Laurent Vivier March 2, 2020, 2:38 p.m. UTC | #2
Le 21/02/2020 à 21:28, Lirong Yuan a écrit :
> This change adds the support for AT_EXECFN and AT_EXECFD auxval.

Why do we need AT_EXECFD?

AT_EXECFD is normally only used with binfmt_misc so I don't see any use
cases for it with QEMU.

For AT_EXECFN, according to kernel commit

  651910874633 execve filename: document and export via auxiliary vector

It sould be like readlink("/proc/self/exe",), and thus I think we should
use realpath() like we have in syscall.c for TARGET_NR_readlink:

 8843     case TARGET_NR_readlink:
...
 8854                 char real[PATH_MAX], *temp;
 8855                 temp = realpath(exec_path, real);
...

Thanks,
Laurent

> 
> Signed-off-by: Lirong Yuan <yuanzi@google.com>
> ---
>  linux-user/elfload.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/linux-user/elfload.c b/linux-user/elfload.c
> index f3080a1635..7e0f3042f1 100644
> --- a/linux-user/elfload.c
> +++ b/linux-user/elfload.c
> @@ -1568,7 +1568,7 @@ struct exec
>                                   ~(abi_ulong)(TARGET_ELF_EXEC_PAGESIZE-1))
>  #define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1))
>  
> -#define DLINFO_ITEMS 15
> +#define DLINFO_ITEMS 17
>  
>  static inline void memcpy_fromfs(void * to, const void * from, unsigned long n)
>  {
> @@ -1888,11 +1888,14 @@ static abi_ulong loader_build_fdpic_loadmap(struct image_info *info, abi_ulong s
>      return sp;
>  }
>  
> -static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
> +static abi_ulong create_elf_tables(struct linux_binprm *bprm,
>                                     struct elfhdr *exec,
>                                     struct image_info *info,
>                                     struct image_info *interp_info)
>  {
> +    abi_ulong p = bprm->p;
> +    int argc = bprm->argc;
> +    int envc = bprm->envc;
>      abi_ulong sp;
>      abi_ulong u_argc, u_argv, u_envp, u_auxv;
>      int size;
> @@ -2032,6 +2035,8 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
>      NEW_AUX_ENT(AT_CLKTCK, (abi_ulong) sysconf(_SC_CLK_TCK));
>      NEW_AUX_ENT(AT_RANDOM, (abi_ulong) u_rand_bytes);
>      NEW_AUX_ENT(AT_SECURE, (abi_ulong) qemu_getauxval(AT_SECURE));
> +    NEW_AUX_ENT(AT_EXECFN, info->file_string);
> +    NEW_AUX_ENT(AT_EXECFD, bprm->fd);
>  
>  #ifdef ELF_HWCAP2
>      NEW_AUX_ENT(AT_HWCAP2, (abi_ulong) ELF_HWCAP2);
> @@ -2870,8 +2875,8 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
>  #endif
>      }
>  
> -    bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &elf_ex,
> -                                info, (elf_interpreter ? &interp_info : NULL));
> +    bprm->p = create_elf_tables(bprm, &elf_ex, info,
> +                                (elf_interpreter ? &interp_info : NULL));
>      info->start_stack = bprm->p;
>  
>      /* If we have an interpreter, set that as the program's entry point.
>
Lirong Yuan March 2, 2020, 6:18 p.m. UTC | #3
On Mon, Mar 2, 2020 at 6:39 AM Laurent Vivier <laurent@vivier.eu> wrote:
>
> Le 21/02/2020 à 21:28, Lirong Yuan a écrit :
> > This change adds the support for AT_EXECFN and AT_EXECFD auxval.
>
> Why do we need AT_EXECFD?
>
> AT_EXECFD is normally only used with binfmt_misc so I don't see any use
> cases for it with QEMU.
>
> For AT_EXECFN, according to kernel commit
>
>   651910874633 execve filename: document and export via auxiliary vector
>
> It sould be like readlink("/proc/self/exe",), and thus I think we should
> use realpath() like we have in syscall.c for TARGET_NR_readlink:
>
>  8843     case TARGET_NR_readlink:
> ...
>  8854                 char real[PATH_MAX], *temp;
>  8855                 temp = realpath(exec_path, real);
> ...
>
> Thanks,
> Laurent
>
> >
> > Signed-off-by: Lirong Yuan <yuanzi@google.com>
> > ---
> >  linux-user/elfload.c | 13 +++++++++----
> >  1 file changed, 9 insertions(+), 4 deletions(-)
> >
> > diff --git a/linux-user/elfload.c b/linux-user/elfload.c
> > index f3080a1635..7e0f3042f1 100644
> > --- a/linux-user/elfload.c
> > +++ b/linux-user/elfload.c
> > @@ -1568,7 +1568,7 @@ struct exec
> >                                   ~(abi_ulong)(TARGET_ELF_EXEC_PAGESIZE-1))
> >  #define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1))
> >
> > -#define DLINFO_ITEMS 15
> > +#define DLINFO_ITEMS 17
> >
> >  static inline void memcpy_fromfs(void * to, const void * from, unsigned long n)
> >  {
> > @@ -1888,11 +1888,14 @@ static abi_ulong loader_build_fdpic_loadmap(struct image_info *info, abi_ulong s
> >      return sp;
> >  }
> >
> > -static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
> > +static abi_ulong create_elf_tables(struct linux_binprm *bprm,
> >                                     struct elfhdr *exec,
> >                                     struct image_info *info,
> >                                     struct image_info *interp_info)
> >  {
> > +    abi_ulong p = bprm->p;
> > +    int argc = bprm->argc;
> > +    int envc = bprm->envc;
> >      abi_ulong sp;
> >      abi_ulong u_argc, u_argv, u_envp, u_auxv;
> >      int size;
> > @@ -2032,6 +2035,8 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
> >      NEW_AUX_ENT(AT_CLKTCK, (abi_ulong) sysconf(_SC_CLK_TCK));
> >      NEW_AUX_ENT(AT_RANDOM, (abi_ulong) u_rand_bytes);
> >      NEW_AUX_ENT(AT_SECURE, (abi_ulong) qemu_getauxval(AT_SECURE));
> > +    NEW_AUX_ENT(AT_EXECFN, info->file_string);
> > +    NEW_AUX_ENT(AT_EXECFD, bprm->fd);
> >
> >  #ifdef ELF_HWCAP2
> >      NEW_AUX_ENT(AT_HWCAP2, (abi_ulong) ELF_HWCAP2);
> > @@ -2870,8 +2875,8 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
> >  #endif
> >      }
> >
> > -    bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &elf_ex,
> > -                                info, (elf_interpreter ? &interp_info : NULL));
> > +    bprm->p = create_elf_tables(bprm, &elf_ex, info,
> > +                                (elf_interpreter ? &interp_info : NULL));
> >      info->start_stack = bprm->p;
> >
> >      /* If we have an interpreter, set that as the program's entry point.
> >
>

Hi Laurent,

I added support for AT_EXECFD because I thought it might be useful to
implement all types that getauxval could take as an argument.
Would you prefer that it be removed?

For AT_EXECFN, there are two questions that we considered:
1) What should it return?
Since QEMU is emulating running the guest program, the function should
return the file name of the guest program (info->file_string), rather
than the QEMU program itself, which we get from
qemu_getauxval(AT_EXECFN).

2) Should it return the full path or as is?
We tested the behavior of getauxval with a simple test program on
Linux, and it turned out that it returned file path as is. For
example,
$ ./test
getauxval(AT_EXECFN): ./test
$ /usr/local/home/tmp/test
getauxval(AT_EXECFN): /usr/local/home/tmp/test

It would seem that the current solution is working as intended.

Thanks,
Lirong
Laurent Vivier March 2, 2020, 6:31 p.m. UTC | #4
Le 02/03/2020 à 19:18, Lirong Yuan a écrit :
> On Mon, Mar 2, 2020 at 6:39 AM Laurent Vivier <laurent@vivier.eu> wrote:
>>
>> Le 21/02/2020 à 21:28, Lirong Yuan a écrit :
>>> This change adds the support for AT_EXECFN and AT_EXECFD auxval.
>>
>> Why do we need AT_EXECFD?
>>
>> AT_EXECFD is normally only used with binfmt_misc so I don't see any use
>> cases for it with QEMU.
>>
>> For AT_EXECFN, according to kernel commit
>>
>>   651910874633 execve filename: document and export via auxiliary vector
>>
>> It sould be like readlink("/proc/self/exe",), and thus I think we should
>> use realpath() like we have in syscall.c for TARGET_NR_readlink:
>>
>>  8843     case TARGET_NR_readlink:
>> ...
>>  8854                 char real[PATH_MAX], *temp;
>>  8855                 temp = realpath(exec_path, real);
>> ...
>>
>> Thanks,
>> Laurent
>>
>>>
>>> Signed-off-by: Lirong Yuan <yuanzi@google.com>
>>> ---
>>>  linux-user/elfload.c | 13 +++++++++----
>>>  1 file changed, 9 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/linux-user/elfload.c b/linux-user/elfload.c
>>> index f3080a1635..7e0f3042f1 100644
>>> --- a/linux-user/elfload.c
>>> +++ b/linux-user/elfload.c
>>> @@ -1568,7 +1568,7 @@ struct exec
>>>                                   ~(abi_ulong)(TARGET_ELF_EXEC_PAGESIZE-1))
>>>  #define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1))
>>>
>>> -#define DLINFO_ITEMS 15
>>> +#define DLINFO_ITEMS 17
>>>
>>>  static inline void memcpy_fromfs(void * to, const void * from, unsigned long n)
>>>  {
>>> @@ -1888,11 +1888,14 @@ static abi_ulong loader_build_fdpic_loadmap(struct image_info *info, abi_ulong s
>>>      return sp;
>>>  }
>>>
>>> -static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
>>> +static abi_ulong create_elf_tables(struct linux_binprm *bprm,
>>>                                     struct elfhdr *exec,
>>>                                     struct image_info *info,
>>>                                     struct image_info *interp_info)
>>>  {
>>> +    abi_ulong p = bprm->p;
>>> +    int argc = bprm->argc;
>>> +    int envc = bprm->envc;
>>>      abi_ulong sp;
>>>      abi_ulong u_argc, u_argv, u_envp, u_auxv;
>>>      int size;
>>> @@ -2032,6 +2035,8 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
>>>      NEW_AUX_ENT(AT_CLKTCK, (abi_ulong) sysconf(_SC_CLK_TCK));
>>>      NEW_AUX_ENT(AT_RANDOM, (abi_ulong) u_rand_bytes);
>>>      NEW_AUX_ENT(AT_SECURE, (abi_ulong) qemu_getauxval(AT_SECURE));
>>> +    NEW_AUX_ENT(AT_EXECFN, info->file_string);
>>> +    NEW_AUX_ENT(AT_EXECFD, bprm->fd);
>>>
>>>  #ifdef ELF_HWCAP2
>>>      NEW_AUX_ENT(AT_HWCAP2, (abi_ulong) ELF_HWCAP2);
>>> @@ -2870,8 +2875,8 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
>>>  #endif
>>>      }
>>>
>>> -    bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &elf_ex,
>>> -                                info, (elf_interpreter ? &interp_info : NULL));
>>> +    bprm->p = create_elf_tables(bprm, &elf_ex, info,
>>> +                                (elf_interpreter ? &interp_info : NULL));
>>>      info->start_stack = bprm->p;
>>>
>>>      /* If we have an interpreter, set that as the program's entry point.
>>>
>>
> 
> Hi Laurent,

Hi Lirong,

> I added support for AT_EXECFD because I thought it might be useful to
> implement all types that getauxval could take as an argument.
> Would you prefer that it be removed?

I think providing the AT_EXECFD to the target binary could make it think
it has been run directly by binfmt_misc (as an interpreter itself), and
that is not the case (qemu is run by binfmt_misc and is the interpreter).

So I would prefer you remove it.

> For AT_EXECFN, there are two questions that we considered:
> 1) What should it return?
> Since QEMU is emulating running the guest program, the function should
> return the file name of the guest program (info->file_string), rather
> than the QEMU program itself, which we get from
> qemu_getauxval(AT_EXECFN).
> 
> 2) Should it return the full path or as is?
> We tested the behavior of getauxval with a simple test program on
> Linux, and it turned out that it returned file path as is. For
> example,
> $ ./test
> getauxval(AT_EXECFN): ./test
> $ /usr/local/home/tmp/test
> getauxval(AT_EXECFN): /usr/local/home/tmp/test

If you have compared the result with the real one it's fine for me.

Resend tou patch without the AT_EXECFD part and it will be good.

Thanks,
Laurent
Lirong Yuan March 2, 2020, 7:54 p.m. UTC | #5
On Mon, Mar 2, 2020 at 10:31 AM Laurent Vivier <laurent@vivier.eu> wrote:
>
> Le 02/03/2020 à 19:18, Lirong Yuan a écrit :
> > On Mon, Mar 2, 2020 at 6:39 AM Laurent Vivier <laurent@vivier.eu> wrote:
> >>
> >> Le 21/02/2020 à 21:28, Lirong Yuan a écrit :
> >>> This change adds the support for AT_EXECFN and AT_EXECFD auxval.
> >>
> >> Why do we need AT_EXECFD?
> >>
> >> AT_EXECFD is normally only used with binfmt_misc so I don't see any use
> >> cases for it with QEMU.
> >>
> >> For AT_EXECFN, according to kernel commit
> >>
> >>   651910874633 execve filename: document and export via auxiliary vector
> >>
> >> It sould be like readlink("/proc/self/exe",), and thus I think we should
> >> use realpath() like we have in syscall.c for TARGET_NR_readlink:
> >>
> >>  8843     case TARGET_NR_readlink:
> >> ...
> >>  8854                 char real[PATH_MAX], *temp;
> >>  8855                 temp = realpath(exec_path, real);
> >> ...
> >>
> >> Thanks,
> >> Laurent
> >>
> >>>
> >>> Signed-off-by: Lirong Yuan <yuanzi@google.com>
> >>> ---
> >>>  linux-user/elfload.c | 13 +++++++++----
> >>>  1 file changed, 9 insertions(+), 4 deletions(-)
> >>>
> >>> diff --git a/linux-user/elfload.c b/linux-user/elfload.c
> >>> index f3080a1635..7e0f3042f1 100644
> >>> --- a/linux-user/elfload.c
> >>> +++ b/linux-user/elfload.c
> >>> @@ -1568,7 +1568,7 @@ struct exec
> >>>                                   ~(abi_ulong)(TARGET_ELF_EXEC_PAGESIZE-1))
> >>>  #define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1))
> >>>
> >>> -#define DLINFO_ITEMS 15
> >>> +#define DLINFO_ITEMS 17
> >>>
> >>>  static inline void memcpy_fromfs(void * to, const void * from, unsigned long n)
> >>>  {
> >>> @@ -1888,11 +1888,14 @@ static abi_ulong loader_build_fdpic_loadmap(struct image_info *info, abi_ulong s
> >>>      return sp;
> >>>  }
> >>>
> >>> -static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
> >>> +static abi_ulong create_elf_tables(struct linux_binprm *bprm,
> >>>                                     struct elfhdr *exec,
> >>>                                     struct image_info *info,
> >>>                                     struct image_info *interp_info)
> >>>  {
> >>> +    abi_ulong p = bprm->p;
> >>> +    int argc = bprm->argc;
> >>> +    int envc = bprm->envc;
> >>>      abi_ulong sp;
> >>>      abi_ulong u_argc, u_argv, u_envp, u_auxv;
> >>>      int size;
> >>> @@ -2032,6 +2035,8 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
> >>>      NEW_AUX_ENT(AT_CLKTCK, (abi_ulong) sysconf(_SC_CLK_TCK));
> >>>      NEW_AUX_ENT(AT_RANDOM, (abi_ulong) u_rand_bytes);
> >>>      NEW_AUX_ENT(AT_SECURE, (abi_ulong) qemu_getauxval(AT_SECURE));
> >>> +    NEW_AUX_ENT(AT_EXECFN, info->file_string);
> >>> +    NEW_AUX_ENT(AT_EXECFD, bprm->fd);
> >>>
> >>>  #ifdef ELF_HWCAP2
> >>>      NEW_AUX_ENT(AT_HWCAP2, (abi_ulong) ELF_HWCAP2);
> >>> @@ -2870,8 +2875,8 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
> >>>  #endif
> >>>      }
> >>>
> >>> -    bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &elf_ex,
> >>> -                                info, (elf_interpreter ? &interp_info : NULL));
> >>> +    bprm->p = create_elf_tables(bprm, &elf_ex, info,
> >>> +                                (elf_interpreter ? &interp_info : NULL));
> >>>      info->start_stack = bprm->p;
> >>>
> >>>      /* If we have an interpreter, set that as the program's entry point.
> >>>
> >>
> >
> > Hi Laurent,
>
> Hi Lirong,
>
> > I added support for AT_EXECFD because I thought it might be useful to
> > implement all types that getauxval could take as an argument.
> > Would you prefer that it be removed?
>
> I think providing the AT_EXECFD to the target binary could make it think
> it has been run directly by binfmt_misc (as an interpreter itself), and
> that is not the case (qemu is run by binfmt_misc and is the interpreter).
>
> So I would prefer you remove it.
>
> > For AT_EXECFN, there are two questions that we considered:
> > 1) What should it return?
> > Since QEMU is emulating running the guest program, the function should
> > return the file name of the guest program (info->file_string), rather
> > than the QEMU program itself, which we get from
> > qemu_getauxval(AT_EXECFN).
> >
> > 2) Should it return the full path or as is?
> > We tested the behavior of getauxval with a simple test program on
> > Linux, and it turned out that it returned file path as is. For
> > example,
> > $ ./test
> > getauxval(AT_EXECFN): ./test
> > $ /usr/local/home/tmp/test
> > getauxval(AT_EXECFN): /usr/local/home/tmp/test
>
> If you have compared the result with the real one it's fine for me.
>
> Resend tou patch without the AT_EXECFD part and it will be good.
>
> Thanks,
> Laurent
>

Hi Laurent,

Thank you so much for the review! :)

Resent the v2 patch without AT_EXECFD:
http://patchwork.ozlabs.org/patch/1247861/

Thanks,
Lirong

Patch
diff mbox series

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index f3080a1635..7e0f3042f1 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -1568,7 +1568,7 @@  struct exec
                                  ~(abi_ulong)(TARGET_ELF_EXEC_PAGESIZE-1))
 #define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1))
 
-#define DLINFO_ITEMS 15
+#define DLINFO_ITEMS 17
 
 static inline void memcpy_fromfs(void * to, const void * from, unsigned long n)
 {
@@ -1888,11 +1888,14 @@  static abi_ulong loader_build_fdpic_loadmap(struct image_info *info, abi_ulong s
     return sp;
 }
 
-static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
+static abi_ulong create_elf_tables(struct linux_binprm *bprm,
                                    struct elfhdr *exec,
                                    struct image_info *info,
                                    struct image_info *interp_info)
 {
+    abi_ulong p = bprm->p;
+    int argc = bprm->argc;
+    int envc = bprm->envc;
     abi_ulong sp;
     abi_ulong u_argc, u_argv, u_envp, u_auxv;
     int size;
@@ -2032,6 +2035,8 @@  static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
     NEW_AUX_ENT(AT_CLKTCK, (abi_ulong) sysconf(_SC_CLK_TCK));
     NEW_AUX_ENT(AT_RANDOM, (abi_ulong) u_rand_bytes);
     NEW_AUX_ENT(AT_SECURE, (abi_ulong) qemu_getauxval(AT_SECURE));
+    NEW_AUX_ENT(AT_EXECFN, info->file_string);
+    NEW_AUX_ENT(AT_EXECFD, bprm->fd);
 
 #ifdef ELF_HWCAP2
     NEW_AUX_ENT(AT_HWCAP2, (abi_ulong) ELF_HWCAP2);
@@ -2870,8 +2875,8 @@  int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
 #endif
     }
 
-    bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &elf_ex,
-                                info, (elf_interpreter ? &interp_info : NULL));
+    bprm->p = create_elf_tables(bprm, &elf_ex, info,
+                                (elf_interpreter ? &interp_info : NULL));
     info->start_stack = bprm->p;
 
     /* If we have an interpreter, set that as the program's entry point.