mips: pldd: support DT_MIPS_RLD_MAP and DT_MIPS_RLD_MAP_REL
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Context |
Check |
Description |
dj/TryBot-apply_patch |
success
|
Patch applied to master at the time it was sent
|
dj/TryBot-32bit |
success
|
Build for i686
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Commit Message
MIPS uses DT_MIPS_RLD_MAP and DT_MIPS_RLD_MAP_REL for accessing r_debug,
instead of DT_DEBUG.
---
elf/pldd-xx.c | 67 ++++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 53 insertions(+), 14 deletions(-)
Comments
On Fri, Jan 28, 2022 at 10:57 AM Xi Ruoyao via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> MIPS uses DT_MIPS_RLD_MAP and DT_MIPS_RLD_MAP_REL for accessing r_debug,
> instead of DT_DEBUG.
> ---
> elf/pldd-xx.c | 67 ++++++++++++++++++++++++++++++++++++++++-----------
> 1 file changed, 53 insertions(+), 14 deletions(-)
>
> diff --git a/elf/pldd-xx.c b/elf/pldd-xx.c
> index 1cdfb49c53..ec397f00e5 100644
> --- a/elf/pldd-xx.c
> +++ b/elf/pldd-xx.c
> @@ -22,6 +22,12 @@
> #define EW_(e, w, t) EW__(e, w, _##t)
> #define EW__(e, w, t) e##w##t
>
> +#if CLASS == 32
> +typedef Elf32_Word E(val_type);
> +#else
> +typedef Elf64_Xword E(val_type);
> +#endif
> +
> struct E(link_map)
> {
> EW(Addr) l_addr;
> @@ -70,6 +76,35 @@ _Static_assert (offsetof (struct r_debug, r_map)
> == offsetof (struct E(r_debug), r_map), "r_map");
> #endif
>
> +static EW(Addr)
> +E(r_debug_offset) (EW(Dyn) *d, int memfd, EW(Addr) d_addr)
> +{
> +#ifdef __mips__
> + EW(Addr) ptr;
> +
> + switch (d->d_tag)
> + {
> + case DT_MIPS_RLD_MAP_REL:
> + ptr = d_addr + d->d_un.d_val;
> + break;
> + case DT_MIPS_RLD_MAP:
> + ptr = d->d_un.d_ptr;
> + break;
> + default:
> + return 0;
> + }
> +
> + if (pread (memfd, &ptr, sizeof (ptr), ptr) != sizeof (ptr))
> + return 0;
> +
> + return ptr;
> +#else
> + if (d->d_tag == DT_DEBUG)
> + return (off_t) d->d_un.d_ptr;
> +
> + return 0;
> +#endif
> +}
>
> static int
>
> @@ -126,21 +161,25 @@ E(find_maps) (const char *exe, int memfd, pid_t pid, void *auxv,
> != p[i].p_filesz)
> error (EXIT_FAILURE, 0, gettext ("cannot read dynamic section"));
>
> - /* Search for the DT_DEBUG entry. */
> + /* Search for the r_debug struct. */
> for (unsigned int j = 0; j < p[i].p_filesz / sizeof (EW(Dyn)); ++j)
> - if (dyn[j].d_tag == DT_DEBUG && dyn[j].d_un.d_ptr != 0)
> - {
> - struct E(r_debug) r;
> - if (pread (memfd, &r, sizeof (r), dyn[j].d_un.d_ptr)
> - != sizeof (r))
> - error (EXIT_FAILURE, 0, gettext ("cannot read r_debug"));
> -
> - if (r.r_map != 0)
> - {
> - list = r.r_map;
> - break;
> - }
> - }
> + {
> + EW(Addr) d_addr = offset + p[i].p_vaddr + sizeof (EW(Dyn)) * j;
> + EW(Addr) off = E(r_debug_offset)(&dyn[j], memfd, d_addr);
> + if (off != 0)
> + {
> + struct E(r_debug) r;
> + if (pread (memfd, &r, sizeof (r), off)
> + != sizeof (r))
> + error (EXIT_FAILURE, 0, gettext ("cannot read r_debug"));
> +
> + if (r.r_map != 0)
> + {
> + list = r.r_map;
> + break;
> + }
> + }
> + }
>
> free (dyn);
> break;
> --
> 2.35.0
>
>
I think a header file to access r_debug works better. MIPS can provide
one to override the generic header file.
On 28/01/2022 17:45, H.J. Lu via Libc-alpha wrote:
> On Fri, Jan 28, 2022 at 10:57 AM Xi Ruoyao via Libc-alpha
> <libc-alpha@sourceware.org> wrote:
>>
>> MIPS uses DT_MIPS_RLD_MAP and DT_MIPS_RLD_MAP_REL for accessing r_debug,
>> instead of DT_DEBUG.
>> ---
>> elf/pldd-xx.c | 67 ++++++++++++++++++++++++++++++++++++++++-----------
>> 1 file changed, 53 insertions(+), 14 deletions(-)
>>
>> diff --git a/elf/pldd-xx.c b/elf/pldd-xx.c
>> index 1cdfb49c53..ec397f00e5 100644
>> --- a/elf/pldd-xx.c
>> +++ b/elf/pldd-xx.c
>> @@ -22,6 +22,12 @@
>> #define EW_(e, w, t) EW__(e, w, _##t)
>> #define EW__(e, w, t) e##w##t
>>
>> +#if CLASS == 32
>> +typedef Elf32_Word E(val_type);
>> +#else
>> +typedef Elf64_Xword E(val_type);
>> +#endif
>> +
>> struct E(link_map)
>> {
>> EW(Addr) l_addr;
>> @@ -70,6 +76,35 @@ _Static_assert (offsetof (struct r_debug, r_map)
>> == offsetof (struct E(r_debug), r_map), "r_map");
>> #endif
>>
>> +static EW(Addr)
>> +E(r_debug_offset) (EW(Dyn) *d, int memfd, EW(Addr) d_addr)
>> +{
>> +#ifdef __mips__
>> + EW(Addr) ptr;
>> +
>> + switch (d->d_tag)
>> + {
>> + case DT_MIPS_RLD_MAP_REL:
>> + ptr = d_addr + d->d_un.d_val;
>> + break;
>> + case DT_MIPS_RLD_MAP:
>> + ptr = d->d_un.d_ptr;
>> + break;
>> + default:
>> + return 0;
>> + }
>> +
>> + if (pread (memfd, &ptr, sizeof (ptr), ptr) != sizeof (ptr))
>> + return 0;
>> +
>> + return ptr;
>> +#else
>> + if (d->d_tag == DT_DEBUG)
>> + return (off_t) d->d_un.d_ptr;
>> +
>> + return 0;
>> +#endif
>> +}
>>
>> static int
>>
>> @@ -126,21 +161,25 @@ E(find_maps) (const char *exe, int memfd, pid_t pid, void *auxv,
>> != p[i].p_filesz)
>> error (EXIT_FAILURE, 0, gettext ("cannot read dynamic section"));
>>
>> - /* Search for the DT_DEBUG entry. */
>> + /* Search for the r_debug struct. */
>> for (unsigned int j = 0; j < p[i].p_filesz / sizeof (EW(Dyn)); ++j)
>> - if (dyn[j].d_tag == DT_DEBUG && dyn[j].d_un.d_ptr != 0)
>> - {
>> - struct E(r_debug) r;
>> - if (pread (memfd, &r, sizeof (r), dyn[j].d_un.d_ptr)
>> - != sizeof (r))
>> - error (EXIT_FAILURE, 0, gettext ("cannot read r_debug"));
>> -
>> - if (r.r_map != 0)
>> - {
>> - list = r.r_map;
>> - break;
>> - }
>> - }
>> + {
>> + EW(Addr) d_addr = offset + p[i].p_vaddr + sizeof (EW(Dyn)) * j;
>> + EW(Addr) off = E(r_debug_offset)(&dyn[j], memfd, d_addr);
>> + if (off != 0)
>> + {
>> + struct E(r_debug) r;
>> + if (pread (memfd, &r, sizeof (r), off)
>> + != sizeof (r))
>> + error (EXIT_FAILURE, 0, gettext ("cannot read r_debug"));
>> +
>> + if (r.r_map != 0)
>> + {
>> + list = r.r_map;
>> + break;
>> + }
>> + }
>> + }
>>
>> free (dyn);
>> break;
>> --
>> 2.35.0
>>
>>
>
> I think a header file to access r_debug works better. MIPS can provide
> one to override the generic header file.
>
Agreed, I think we should avoid arch specific defines (__mips__) on generic
code.
On 1/28/22 15:48, Adhemerval Zanella via Libc-alpha wrote:
>
>
> On 28/01/2022 17:45, H.J. Lu via Libc-alpha wrote:
>> On Fri, Jan 28, 2022 at 10:57 AM Xi Ruoyao via Libc-alpha
>> <libc-alpha@sourceware.org> wrote:
>>>
>>> MIPS uses DT_MIPS_RLD_MAP and DT_MIPS_RLD_MAP_REL for accessing r_debug,
>>> instead of DT_DEBUG.
>>> ---
>>> elf/pldd-xx.c | 67 ++++++++++++++++++++++++++++++++++++++++-----------
>>> 1 file changed, 53 insertions(+), 14 deletions(-)
>>>
>>> diff --git a/elf/pldd-xx.c b/elf/pldd-xx.c
>>> index 1cdfb49c53..ec397f00e5 100644
>>> --- a/elf/pldd-xx.c
>>> +++ b/elf/pldd-xx.c
>>> @@ -22,6 +22,12 @@
>>> #define EW_(e, w, t) EW__(e, w, _##t)
>>> #define EW__(e, w, t) e##w##t
>>>
>>> +#if CLASS == 32
>>> +typedef Elf32_Word E(val_type);
>>> +#else
>>> +typedef Elf64_Xword E(val_type);
>>> +#endif
>>> +
>>> struct E(link_map)
>>> {
>>> EW(Addr) l_addr;
>>> @@ -70,6 +76,35 @@ _Static_assert (offsetof (struct r_debug, r_map)
>>> == offsetof (struct E(r_debug), r_map), "r_map");
>>> #endif
>>>
>>> +static EW(Addr)
>>> +E(r_debug_offset) (EW(Dyn) *d, int memfd, EW(Addr) d_addr)
>>> +{
>>> +#ifdef __mips__
>>> + EW(Addr) ptr;
>>> +
>>> + switch (d->d_tag)
>>> + {
>>> + case DT_MIPS_RLD_MAP_REL:
>>> + ptr = d_addr + d->d_un.d_val;
>>> + break;
>>> + case DT_MIPS_RLD_MAP:
>>> + ptr = d->d_un.d_ptr;
>>> + break;
>>> + default:
>>> + return 0;
>>> + }
>>> +
>>> + if (pread (memfd, &ptr, sizeof (ptr), ptr) != sizeof (ptr))
>>> + return 0;
>>> +
>>> + return ptr;
>>> +#else
>>> + if (d->d_tag == DT_DEBUG)
>>> + return (off_t) d->d_un.d_ptr;
>>> +
>>> + return 0;
>>> +#endif
>>> +}
>>>
>>> static int
>>>
>>> @@ -126,21 +161,25 @@ E(find_maps) (const char *exe, int memfd, pid_t pid, void *auxv,
>>> != p[i].p_filesz)
>>> error (EXIT_FAILURE, 0, gettext ("cannot read dynamic section"));
>>>
>>> - /* Search for the DT_DEBUG entry. */
>>> + /* Search for the r_debug struct. */
>>> for (unsigned int j = 0; j < p[i].p_filesz / sizeof (EW(Dyn)); ++j)
>>> - if (dyn[j].d_tag == DT_DEBUG && dyn[j].d_un.d_ptr != 0)
>>> - {
>>> - struct E(r_debug) r;
>>> - if (pread (memfd, &r, sizeof (r), dyn[j].d_un.d_ptr)
>>> - != sizeof (r))
>>> - error (EXIT_FAILURE, 0, gettext ("cannot read r_debug"));
>>> -
>>> - if (r.r_map != 0)
>>> - {
>>> - list = r.r_map;
>>> - break;
>>> - }
>>> - }
>>> + {
>>> + EW(Addr) d_addr = offset + p[i].p_vaddr + sizeof (EW(Dyn)) * j;
>>> + EW(Addr) off = E(r_debug_offset)(&dyn[j], memfd, d_addr);
>>> + if (off != 0)
>>> + {
>>> + struct E(r_debug) r;
>>> + if (pread (memfd, &r, sizeof (r), off)
>>> + != sizeof (r))
>>> + error (EXIT_FAILURE, 0, gettext ("cannot read r_debug"));
>>> +
>>> + if (r.r_map != 0)
>>> + {
>>> + list = r.r_map;
>>> + break;
>>> + }
>>> + }
>>> + }
>>>
>>> free (dyn);
>>> break;
>>> --
>>> 2.35.0
>>>
>>>
>>
>> I think a header file to access r_debug works better. MIPS can provide
>> one to override the generic header file.
>>
>
> Agreed, I think we should avoid arch specific defines (__mips__) on generic
> code.
Ah! I see, the objection if about arch-defines in tests. Yes, lets clean that up.
@@ -22,6 +22,12 @@
#define EW_(e, w, t) EW__(e, w, _##t)
#define EW__(e, w, t) e##w##t
+#if CLASS == 32
+typedef Elf32_Word E(val_type);
+#else
+typedef Elf64_Xword E(val_type);
+#endif
+
struct E(link_map)
{
EW(Addr) l_addr;
@@ -70,6 +76,35 @@ _Static_assert (offsetof (struct r_debug, r_map)
== offsetof (struct E(r_debug), r_map), "r_map");
#endif
+static EW(Addr)
+E(r_debug_offset) (EW(Dyn) *d, int memfd, EW(Addr) d_addr)
+{
+#ifdef __mips__
+ EW(Addr) ptr;
+
+ switch (d->d_tag)
+ {
+ case DT_MIPS_RLD_MAP_REL:
+ ptr = d_addr + d->d_un.d_val;
+ break;
+ case DT_MIPS_RLD_MAP:
+ ptr = d->d_un.d_ptr;
+ break;
+ default:
+ return 0;
+ }
+
+ if (pread (memfd, &ptr, sizeof (ptr), ptr) != sizeof (ptr))
+ return 0;
+
+ return ptr;
+#else
+ if (d->d_tag == DT_DEBUG)
+ return (off_t) d->d_un.d_ptr;
+
+ return 0;
+#endif
+}
static int
@@ -126,21 +161,25 @@ E(find_maps) (const char *exe, int memfd, pid_t pid, void *auxv,
!= p[i].p_filesz)
error (EXIT_FAILURE, 0, gettext ("cannot read dynamic section"));
- /* Search for the DT_DEBUG entry. */
+ /* Search for the r_debug struct. */
for (unsigned int j = 0; j < p[i].p_filesz / sizeof (EW(Dyn)); ++j)
- if (dyn[j].d_tag == DT_DEBUG && dyn[j].d_un.d_ptr != 0)
- {
- struct E(r_debug) r;
- if (pread (memfd, &r, sizeof (r), dyn[j].d_un.d_ptr)
- != sizeof (r))
- error (EXIT_FAILURE, 0, gettext ("cannot read r_debug"));
-
- if (r.r_map != 0)
- {
- list = r.r_map;
- break;
- }
- }
+ {
+ EW(Addr) d_addr = offset + p[i].p_vaddr + sizeof (EW(Dyn)) * j;
+ EW(Addr) off = E(r_debug_offset)(&dyn[j], memfd, d_addr);
+ if (off != 0)
+ {
+ struct E(r_debug) r;
+ if (pread (memfd, &r, sizeof (r), off)
+ != sizeof (r))
+ error (EXIT_FAILURE, 0, gettext ("cannot read r_debug"));
+
+ if (r.r_map != 0)
+ {
+ list = r.r_map;
+ break;
+ }
+ }
+ }
free (dyn);
break;