From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1944) id EF4763851517; Thu, 27 Oct 2022 14:00:45 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org EF4763851517 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1666879255; bh=STJeZI7K+MuaDuhCmmExUn8ksD2avbTSYBaftpftCe8=; h=From:To:Subject:Date:From; b=G4fzPKslpHnUgPT9fL7+BEEz/JptRfTUZY37ULc+pxUjnyVS44cYZyPLllFIEBewb o2FsAZ9qGCzvEWuN8UAUdRmHyqtASwfg97cReOxtw3I3aAKR+UlvllPuqm2Jikrkv8 00YxMRRsBnu1bL+YSV46HSkyaD5qWjYUf4D9V0hU= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Szabolcs Nagy To: glibc-cvs@sourceware.org Subject: [glibc/arm/morello/main] cheri: malloc: add tunable to turn narrowing off X-Act-Checkin: glibc X-Git-Author: Szabolcs Nagy X-Git-Refname: refs/heads/arm/morello/main X-Git-Oldrev: b488de1ab2c613641c198f82c840b88a4d299fb4 X-Git-Newrev: f0f77b883f9e74e6843081af280aa291a9182601 Message-Id: <20221027140055.EF4763851517@sourceware.org> Date: Thu, 27 Oct 2022 14:00:45 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=f0f77b883f9e74e6843081af280aa291a9182601 commit f0f77b883f9e74e6843081af280aa291a9182601 Author: Szabolcs Nagy Date: Thu Oct 6 12:00:39 2022 +0100 cheri: malloc: add tunable to turn narrowing off Diff: --- elf/dl-tunables.list | 7 +++++++ malloc/arena.c | 6 ++++++ manual/tunables.texi | 6 ++++++ 3 files changed, 19 insertions(+) diff --git a/elf/dl-tunables.list b/elf/dl-tunables.list index e6a56b3070..83f47dcd9a 100644 --- a/elf/dl-tunables.list +++ b/elf/dl-tunables.list @@ -159,6 +159,13 @@ glibc { maxval: 255 security_level: SXID_IGNORE } + cap_narrowing { + type: INT_32 + minval: 0 + maxval: 1 + default: 1 + security_level: SXID_IGNORE + } } rtld { diff --git a/malloc/arena.c b/malloc/arena.c index 894f49b911..85cc2ad066 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -326,6 +326,12 @@ ptmalloc_init (void) tcache_key_initialize (); #endif +#ifdef __CHERI_PURE_CAPABILITY__ + if (TUNABLE_GET_FULL (glibc, mem, cap_narrowing, int32_t, NULL) == 0) + cap_narrowing_enabled = false; + else + cap_narrowing_enabled = true; +#endif cap_init (); #ifdef USE_MTAG diff --git a/manual/tunables.texi b/manual/tunables.texi index 83cdcdac6d..ffe0202627 100644 --- a/manual/tunables.texi +++ b/manual/tunables.texi @@ -612,3 +612,9 @@ support in the kernel if this tunable has any non-zero value. The default value is @samp{0}, which disables all memory tagging. @end deftp + +@deftp Tunable glibc.mem.cap_narrowing +On CHERI architecture use capability bounds narrowing in the malloc +implementation. By default it is set to 1, to disable bounds narrowing +set it to 0. +@end deftp