It consolidates the code required to call la_pltenter() audit
callback.
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
---
elf/dl-audit.c | 77 ++++++++++++++++++++++++++++++++++++++
elf/dl-runtime.c | 73 +-----------------------------------
sysdeps/generic/ldsodefs.h | 3 ++
3 files changed, 81 insertions(+), 72 deletions(-)
@@ -17,7 +17,9 @@
<https://www.gnu.org/licenses/>. */
#include <assert.h>
+#include <link.h>
#include <ldsodefs.h>
+#include <dl-machine.h>
#ifdef SHARED
void
@@ -257,4 +259,79 @@ _dl_audit_symbind (struct link_map *l, struct reloc_result *reloc_result,
reloc_result->flags = flags;
*value = DL_FIXUP_ADDR_VALUE (sym.st_value);
}
+
+void
+_dl_audit_pltenter (struct link_map *l, struct reloc_result *reloc_result,
+ DL_FIXUP_VALUE_TYPE *value, void *regs, long int *framesize)
+{
+ /* Don't do anything if no auditor wants to intercept this call. */
+ if (GLRO(dl_naudit) == 0
+ || (reloc_result->enterexit & LA_SYMB_NOPLTENTER))
+ return;
+
+ /* Sanity check: DL_FIXUP_VALUE_CODE_ADDR (value) should have been
+ initialized earlier in this function or in another thread. */
+ assert (DL_FIXUP_VALUE_CODE_ADDR (*value) != 0);
+ ElfW(Sym) *defsym = ((ElfW(Sym) *) D_PTR (reloc_result->bound,
+ l_info[DT_SYMTAB])
+ + reloc_result->boundndx);
+
+ /* Set up the sym parameter. */
+ ElfW(Sym) sym = *defsym;
+ sym.st_value = DL_FIXUP_VALUE_ADDR (*value);
+
+ /* Get the symbol name. */
+ const char *strtab = (const void *) D_PTR (reloc_result->bound,
+ l_info[DT_STRTAB]);
+ const char *symname = strtab + sym.st_name;
+
+ /* Keep track of overwritten addresses. */
+ unsigned int flags = reloc_result->flags;
+
+ struct audit_ifaces *afct = GLRO(dl_audit);
+ for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
+ {
+ if (afct->ARCH_LA_PLTENTER != NULL
+ && (reloc_result->enterexit
+ & (LA_SYMB_NOPLTENTER << (2 * (cnt + 1)))) == 0)
+ {
+ long int new_framesize = -1;
+ struct auditstate *l_state = link_map_audit_state (l, cnt);
+ struct auditstate *bound_state
+ = link_map_audit_state (reloc_result->bound, cnt);
+ uintptr_t new_value
+ = afct->ARCH_LA_PLTENTER (&sym, reloc_result->boundndx,
+ &l_state->cookie, &bound_state->cookie,
+ regs, &flags, symname, &new_framesize);
+ if (new_value != (uintptr_t) sym.st_value)
+ {
+ flags |= LA_SYMB_ALTVALUE;
+ sym.st_value = new_value;
+ }
+
+ /* Remember the results for every audit library and store a summary
+ in the first two bits. */
+ reloc_result->enterexit |= ((flags & (LA_SYMB_NOPLTENTER
+ | LA_SYMB_NOPLTEXIT))
+ << (2 * (cnt + 1)));
+
+ if ((reloc_result->enterexit & (LA_SYMB_NOPLTEXIT
+ << (2 * (cnt + 1))))
+ == 0 && new_framesize != -1 && *framesize != -2)
+ {
+ /* If this is the first call providing information, use it. */
+ if (*framesize == -1)
+ *framesize = new_framesize;
+ /* If two pltenter calls provide conflicting information, use
+ the larger value. */
+ else if (new_framesize != *framesize)
+ *framesize = MAX (new_framesize, *framesize);
+ }
+ }
+
+ afct = afct->next;
+ }
+
+ *value = DL_FIXUP_ADDR_VALUE (sym.st_value);
+}
#endif
@@ -352,78 +352,7 @@ _dl_profile_fixup (
#ifdef SHARED
/* Auditing checkpoint: report the PLT entering and allow the
auditors to change the value. */
- if (GLRO(dl_naudit) > 0
- /* Don't do anything if no auditor wants to intercept this call. */
- && (reloc_result->enterexit & LA_SYMB_NOPLTENTER) == 0)
- {
- /* Sanity check: DL_FIXUP_VALUE_CODE_ADDR (value) should have been
- initialized earlier in this function or in another thread. */
- assert (DL_FIXUP_VALUE_CODE_ADDR (value) != 0);
- ElfW(Sym) *defsym = ((ElfW(Sym) *) D_PTR (reloc_result->bound,
- l_info[DT_SYMTAB])
- + reloc_result->boundndx);
-
- /* Set up the sym parameter. */
- ElfW(Sym) sym = *defsym;
- sym.st_value = DL_FIXUP_VALUE_ADDR (value);
-
- /* Get the symbol name. */
- const char *strtab = (const void *) D_PTR (reloc_result->bound,
- l_info[DT_STRTAB]);
- const char *symname = strtab + sym.st_name;
-
- /* Keep track of overwritten addresses. */
- unsigned int flags = reloc_result->flags;
-
- struct audit_ifaces *afct = GLRO(dl_audit);
- for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
- {
- if (afct->ARCH_LA_PLTENTER != NULL
- && (reloc_result->enterexit
- & (LA_SYMB_NOPLTENTER << (2 * (cnt + 1)))) == 0)
- {
- long int new_framesize = -1;
- struct auditstate *l_state = link_map_audit_state (l, cnt);
- struct auditstate *bound_state
- = link_map_audit_state (reloc_result->bound, cnt);
- uintptr_t new_value
- = afct->ARCH_LA_PLTENTER (&sym, reloc_result->boundndx,
- &l_state->cookie,
- &bound_state->cookie,
- regs, &flags, symname,
- &new_framesize);
- if (new_value != (uintptr_t) sym.st_value)
- {
- flags |= LA_SYMB_ALTVALUE;
- sym.st_value = new_value;
- }
-
- /* Remember the results for every audit library and
- store a summary in the first two bits. */
- reloc_result->enterexit
- |= ((flags & (LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT))
- << (2 * (cnt + 1)));
-
- if ((reloc_result->enterexit & (LA_SYMB_NOPLTEXIT
- << (2 * (cnt + 1))))
- == 0 && new_framesize != -1 && framesize != -2)
- {
- /* If this is the first call providing information,
- use it. */
- if (framesize == -1)
- framesize = new_framesize;
- /* If two pltenter calls provide conflicting information,
- use the larger value. */
- else if (new_framesize != framesize)
- framesize = MAX (new_framesize, framesize);
- }
- }
-
- afct = afct->next;
- }
-
- value = DL_FIXUP_ADDR_VALUE (sym.st_value);
- }
+ _dl_audit_pltenter (l, reloc_result, &value, regs, &framesize);
#endif
/* Store the frame size information. */
@@ -1382,6 +1382,9 @@ void _dl_audit_symbind (struct link_map *l, struct reloc_result *reloc_result,
void _dl_audit_symbind_alt (struct link_map *l, const ElfW(Sym) *ref,
void **value, lookup_t result);
rtld_hidden_proto (_dl_audit_symbind_alt)
+void _dl_audit_pltenter (struct link_map *l, struct reloc_result *reloc_result,
+ DL_FIXUP_VALUE_TYPE *value, void *regs,
+ long int *framesize);
#endif /* SHARED */
#if PTHREAD_IN_LIBC && defined SHARED