Add bounds check to __libc_ifunc_impl_list

Add a proper bounds check to __libc_ifunc_impl_list. This makes MAX_IFUNC
redundant and fixes several targets that will write outside the array.
To avoid unnecessary large diffs, pass the maximum in the argument 'i' to
IFUNC_IMPL_ADD - 'max' can be used in new ifunc definitions and existing
ones can be updated if desired.

Passes buildmanyglibc.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/sysdeps/arm/armv7/multiarch/ifunc-impl-list.c b/sysdeps/arm/armv7/multiarch/ifunc-impl-list.c
index af9f749045..e92bcb27a2 100644
--- a/sysdeps/arm/armv7/multiarch/ifunc-impl-list.c
+++ b/sysdeps/arm/armv7/multiarch/ifunc-impl-list.c
@@ -29,7 +29,7 @@ size_t
 __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 			size_t max)
 {
-  size_t i = 0;
+  size_t i = max;
 
   bool use_neon = true;
 #ifdef __ARM_NEON__
@@ -57,5 +57,5 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
 	      IFUNC_IMPL_ADD (array, i, memchr, use_neon, __memchr_neon)
 	      IFUNC_IMPL_ADD (array, i, memchr, 1, __memchr_noneon));
 
-  return i;
+  return 0;
 }