DivestOS/Patches/LineageOS-14.1/android_bionic/0003-Add_M_PURGE.patch
Tavi 0c88720caa
14.1: work on integrating hardened_malloc
untested as all currently supported 14.1 devices are 32-bit

Signed-off-by: Tavi <tavi@divested.dev>
2024-05-09 13:46:19 -04:00

54 lines
1.6 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Tim Murray <timmurray@google.com>
Date: Mon, 15 Oct 2018 16:26:56 -0700
Subject: [PATCH] malloc: add M_PURGE mallopt flag
Add a new mallopt flag that purges any pending decaying pages.
Test: boots and works
bug 117795621
Merged-in: Ib250ae2b705b6a368c1efb801d6a7be54e075acb
Change-Id: Ib250ae2b705b6a368c1efb801d6a7be54e075acb
(cherry picked from commit 8a07791fbff0dd014ce5da8d88969d09cd3dcf0b)
---
libc/bionic/jemalloc_wrapper.cpp | 12 ++++++++++++
libc/include/malloc.h | 1 +
2 files changed, 13 insertions(+)
diff --git a/libc/bionic/jemalloc_wrapper.cpp b/libc/bionic/jemalloc_wrapper.cpp
index 266b9660c..b4678d008 100644
--- a/libc/bionic/jemalloc_wrapper.cpp
+++ b/libc/bionic/jemalloc_wrapper.cpp
@@ -79,6 +79,18 @@ int je_mallopt(int param, int value) {
}
}
return 1;
+ } else if (param == M_PURGE) {
+ unsigned narenas;
+ size_t sz = sizeof(unsigned);
+ if (je_mallctl("arenas.narenas", &narenas, &sz, nullptr, 0) != 0) {
+ return 0;
+ }
+ char buffer[100];
+ snprintf(buffer, sizeof(buffer), "arena.%u.purge", narenas);
+ if (je_mallctl(buffer, nullptr, nullptr, nullptr, 0) != 0) {
+ return 0;
+ }
+ return 1;
}
return 0;
}
diff --git a/libc/include/malloc.h b/libc/include/malloc.h
index f0cdf82f3..50ae7d6a7 100644
--- a/libc/include/malloc.h
+++ b/libc/include/malloc.h
@@ -72,6 +72,7 @@ extern int malloc_info(int, FILE *);
/* mallopt options */
#define M_DECAY_TIME -100
+#define M_PURGE -101
int mallopt(int, int) __INTRODUCED_IN(26);