From 0232af1ad6cbd8378025e804f535ce9449ad49de Mon Sep 17 00:00:00 2001 From: Siddhesh Poyarekar Date: Thu, 9 Feb 2017 17:28:54 +0100 Subject: [PATCH] Fix getting tunable values on big-endian (BZ #21109) The code to set value passed a tunable_val_t, which when cast to int32_t on big-endian gives the wrong value. Instead, use tunable_val_t.numval instead, which can then be safely cast into int32_t. (cherry picked from commit 8cbc826c37c0221ada65a7a622fe079b4e89a4b0) (cherry picked from commit 58520986c38e34db60e07260c64c563e3efcf353) --- elf/dl-tunable-types.h | 4 ++-- elf/dl-tunables.c | 2 ++ malloc/arena.c | 8 ++++---- 3 files changed, 8 insertions(+), 6 deletions(-) diff --git a/elf/dl-tunable-types.h b/elf/dl-tunable-types.h index a986f0b593..37a4e8021f 100644 --- a/elf/dl-tunable-types.h +++ b/elf/dl-tunable-types.h @@ -21,8 +21,6 @@ # define _TUNABLE_TYPES_H_ #include -typedef void (*tunable_callback_t) (void *); - typedef enum { TUNABLE_TYPE_INT_32, @@ -43,6 +41,8 @@ typedef union const char *strval; } tunable_val_t; +typedef void (*tunable_callback_t) (tunable_val_t *); + /* Security level for tunables. This decides what to do with individual tunables for AT_SECURE binaries. */ typedef enum diff --git a/elf/dl-tunables.c b/elf/dl-tunables.c index a8d53d6a31..e42aa67003 100644 --- a/elf/dl-tunables.c +++ b/elf/dl-tunables.c @@ -455,6 +455,8 @@ __tunable_set_val (tunable_id_t id, void *valp, tunable_callback_t callback) if (cur->strval == NULL) return; + /* Caller does not need the value, just call the callback with our tunable + value. */ if (valp == NULL) goto cb; diff --git a/malloc/arena.c b/malloc/arena.c index b91d7d6b16..d49e4a21c8 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -212,9 +212,9 @@ __malloc_fork_unlock_child (void) #if HAVE_TUNABLES static inline int do_set_mallopt_check (int32_t value); void -DL_TUNABLE_CALLBACK (set_mallopt_check) (void *valp) +DL_TUNABLE_CALLBACK (set_mallopt_check) (tunable_val_t *valp) { - int32_t value = *(int32_t *) valp; + int32_t value = (int32_t) valp->numval; do_set_mallopt_check (value); if (check_action != 0) __malloc_check_init (); @@ -223,9 +223,9 @@ DL_TUNABLE_CALLBACK (set_mallopt_check) (void *valp) # define DL_TUNABLE_CALLBACK_FNDECL(__name, __type) \ static inline int do_ ## __name (__type value); \ void \ -DL_TUNABLE_CALLBACK (__name) (void *valp) \ +DL_TUNABLE_CALLBACK (__name) (tunable_val_t *valp) \ { \ - __type value = *(__type *) valp; \ + __type value = (__type) (valp)->numval; \ do_ ## __name (value); \ } -- 2.43.5