| commit 9e94f57484a2aba0fe67ea2059b5843f651887c2 |
| Author: Adhemerval Zanella <adhemerval.zanella@linaro.org> |
| Date: Fri Feb 4 15:54:59 2022 -0300 |
| |
| hppa: Fix bind-now audit (BZ #28857) |
| |
| On hppa, a function pointer returned by la_symbind is actually a function |
| descriptor has the plabel bit set (bit 30). This must be cleared to get |
| the actual address of the descriptor. If the descriptor has been bound, |
| the first word of the descriptor is the physical address of theA function, |
| otherwise, the first word of the descriptor points to a trampoline in the |
| PLT. |
| |
| This patch also adds a workaround on tests because on hppa (and it seems |
| to be the only ABI I have see it), some shared library adds a dynamic PLT |
| relocation to am empty symbol name: |
| |
| $ readelf -r elf/tst-audit25mod1.so |
| [...] |
| Relocation section '.rela.plt' at offset 0x464 contains 6 entries: |
| Offset Info Type Sym.Value Sym. Name + Addend |
| 00002008 00000081 R_PARISC_IPLT 508 |
| [...] |
| |
| It breaks some assumptions on the test, where a symbol with an empty |
| name ("") is passed on la_symbind. |
| |
| Checked on x86_64-linux-gnu and hppa-linux-gnu. |
| |
| diff --git a/elf/Makefile b/elf/Makefile |
| index 73d347339762fc9e..6d39b400060a73f3 100644 |
| |
| |
| @@ -2113,7 +2113,7 @@ $(objpfx)tst-audit24c.out: $(objpfx)tst-auditmod24c.so |
| $(objpfx)tst-audit24c: $(objpfx)tst-audit24amod1.so \ |
| $(objpfx)tst-audit24amod2.so |
| tst-audit24c-ENV = LD_BIND_NOW=1 LD_AUDIT=$(objpfx)tst-auditmod24c.so |
| -LDFLAGS-tst-audit24b = -Wl,-z,lazy |
| +LDFLAGS-tst-audit24c = -Wl,-z,lazy |
| |
| $(objpfx)tst-audit24d.out: $(objpfx)tst-auditmod24d.so |
| $(objpfx)tst-audit24d: $(objpfx)tst-audit24dmod1.so \ |
| diff --git a/elf/dl-audit.c b/elf/dl-audit.c |
| index 72a50717ef60a357..ec9b032eae37c103 100644 |
| |
| |
| @@ -257,7 +257,8 @@ _dl_audit_symbind (struct link_map *l, struct reloc_result *reloc_result, |
| reloc_result->flags = flags; |
| } |
| |
| - DL_FIXUP_BINDNOW_RELOC (value, new_value, sym.st_value); |
| + if (flags & LA_SYMB_ALTVALUE) |
| + DL_FIXUP_BINDNOW_RELOC (value, new_value, sym.st_value); |
| } |
| |
| void |
| diff --git a/elf/tst-auditmod24a.c b/elf/tst-auditmod24a.c |
| index d8e88f3984af1707..3075dfae2fd3d288 100644 |
| |
| |
| @@ -110,5 +110,7 @@ la_symbind32 (Elf32_Sym *sym, unsigned int ndx, |
| return sym->st_value; |
| } |
| |
| - abort (); |
| + if (symname[0] != '\0') |
| + abort (); |
| + return sym->st_value; |
| } |
| diff --git a/elf/tst-auditmod24d.c b/elf/tst-auditmod24d.c |
| index 8c803ecc0a48f21b..badc6be451ee0357 100644 |
| |
| |
| @@ -116,5 +116,7 @@ la_symbind32 (Elf32_Sym *sym, unsigned int ndx, |
| } |
| } |
| |
| - abort (); |
| + if (symname[0] != '\0') |
| + abort (); |
| + return sym->st_value; |
| } |
| diff --git a/elf/tst-auditmod25.c b/elf/tst-auditmod25.c |
| index 526f5c54bc2c3b8c..20640a8daf346b5f 100644 |
| |
| |
| @@ -72,7 +72,7 @@ la_symbind32 (Elf32_Sym *sym, unsigned int ndx, |
| unsigned int *flags, const char *symname) |
| #endif |
| { |
| - if (*refcook != -1 && *defcook != -1) |
| + if (*refcook != -1 && *defcook != -1 && symname[0] != '\0') |
| fprintf (stderr, "la_symbind: %s %u\n", symname, |
| *flags & (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT) ? 1 : 0); |
| return sym->st_value; |
| diff --git a/sysdeps/hppa/dl-lookupcfg.h b/sysdeps/hppa/dl-lookupcfg.h |
| index c3fea1fe5776b17a..86f6a04af46c87ba 100644 |
| |
| |
| @@ -79,7 +79,9 @@ void attribute_hidden _dl_unmap (struct link_map *map); |
| /* Extract the code address from a fixup value */ |
| #define DL_FIXUP_VALUE_CODE_ADDR(value) ((value).ip) |
| #define DL_FIXUP_VALUE_ADDR(value) ((uintptr_t) &(value)) |
| -#define DL_FIXUP_ADDR_VALUE(addr) (*(struct fdesc *) (addr)) |
| +/* Clear the plabel bit to get the actual address of the descriptor. */ |
| +#define DL_FIXUP_ADDR_VALUE(addr) \ |
| + (*(DL_FIXUP_VALUE_TYPE *) ((uintptr_t) (addr) & ~2)) |
| #define DL_FIXUP_BINDNOW_ADDR_VALUE(addr) (addr) |
| -#define DL_FIXUP_BINDNOW_RELOC(value, new_value, st_value) \ |
| - (*value) = *(struct fdesc *) (st_value) |
| +#define DL_FIXUP_BINDNOW_RELOC(value, new_value, st_value) \ |
| + *(value) = *(DL_FIXUP_VALUE_TYPE *) ((uintptr_t) (new_value) & ~2) |