| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <CAJF2gTS4=8dMypnWe2dpuQfdfV3+XLq5fZeGbJWZPDN_ypfuvQ@mail.gmail.com> Date: Fri, 6 Sep 2024 14:08:40 +0800 From: Guo Ren <guoren@...nel.org> To: Charlie Jenkins <charlie@...osinc.com> Cc: Arnd Bergmann <arnd@...db.de>, Richard Henderson <richard.henderson@...aro.org>, Ivan Kokshaysky <ink@...assic.park.msu.ru>, Matt Turner <mattst88@...il.com>, Vineet Gupta <vgupta@...nel.org>, Russell King <linux@...linux.org.uk>, Huacai Chen <chenhuacai@...nel.org>, WANG Xuerui <kernel@...0n.name>, Thomas Bogendoerfer <tsbogend@...ha.franken.de>, "James E.J. Bottomley" <James.Bottomley@...senpartnership.com>, Helge Deller <deller@....de>, Michael Ellerman <mpe@...erman.id.au>, Nicholas Piggin <npiggin@...il.com>, Christophe Leroy <christophe.leroy@...roup.eu>, Naveen N Rao <naveen@...nel.org>, Alexander Gordeev <agordeev@...ux.ibm.com>, Gerald Schaefer <gerald.schaefer@...ux.ibm.com>, Heiko Carstens <hca@...ux.ibm.com>, Vasily Gorbik <gor@...ux.ibm.com>, Christian Borntraeger <borntraeger@...ux.ibm.com>, Sven Schnelle <svens@...ux.ibm.com>, Yoshinori Sato <ysato@...rs.sourceforge.jp>, Rich Felker <dalias@...c.org>, John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de>, "David S. Miller" <davem@...emloft.net>, Andreas Larsson <andreas@...sler.com>, Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>, Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org, "H. Peter Anvin" <hpa@...or.com>, Andy Lutomirski <luto@...nel.org>, Peter Zijlstra <peterz@...radead.org>, Muchun Song <muchun.song@...ux.dev>, Andrew Morton <akpm@...ux-foundation.org>, "Liam R. Howlett" <Liam.Howlett@...cle.com>, Vlastimil Babka <vbabka@...e.cz>, Lorenzo Stoakes <lorenzo.stoakes@...cle.com>, Shuah Khan <shuah@...nel.org>, Christoph Hellwig <hch@...radead.org>, Michal Hocko <mhocko@...e.com>, "Kirill A. Shutemov" <kirill@...temov.name>, Chris Torek <chris.torek@...il.com>, linux-arch@...r.kernel.org, linux-kernel@...r.kernel.org, linux-alpha@...r.kernel.org, linux-snps-arc@...ts.infradead.org, linux-arm-kernel@...ts.infradead.org, linux-csky@...r.kernel.org, loongarch@...ts.linux.dev, linux-mips@...r.kernel.org, linux-parisc@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org, linux-s390@...r.kernel.org, linux-sh@...r.kernel.org, sparclinux@...r.kernel.org, linux-mm@...ck.org, linux-kselftest@...r.kernel.org, linux-abi-devel@...ts.sourceforge.net Subject: Re: [PATCH RFC v3 0/2] mm: Introduce ADDR_LIMIT_47BIT personality flag On Fri, Sep 6, 2024 at 5:16 AM Charlie Jenkins <charlie@...osinc.com> wrote: > > Some applications rely on placing data in free bits addresses allocated > by mmap. Various architectures (eg. x86, arm64, powerpc) restrict the > address returned by mmap to be less than the 48-bit address space, > unless the hint address uses more than 47 bits (the 48th bit is reserved > for the kernel address space). > > The riscv architecture needs a way to similarly restrict the virtual > address space. On the riscv port of OpenJDK an error is thrown if > attempted to run on the 57-bit address space, called sv57 [1]. golang > has a comment that sv57 support is not complete, but there are some > workarounds to get it to mostly work [2]. > > These applications work on x86 because x86 does an implicit 47-bit > restriction of mmap() address that contain a hint address that is less > than 48 bits. > > Instead of implicitly restricting the address space on riscv (or any > current/future architecture), provide a flag to the personality syscall > that can be used to ensure an application works in any arbitrary VA > space. A similar feature has already been implemented by the personality > syscall in ADDR_LIMIT_32BIT. > > This flag will also allow seemless compatibility between all > architectures, so applications like Go and OpenJDK that use bits in a > virtual address can request the exact number of bits they need in a > generic way. The flag can be checked inside of vm_unmapped_area() so > that this flag does not have to be handled individually by each > architecture. Acked-by: Guo Ren <guoren@...nel.org> Sv57's pain finds its cure in this antidote. > > Link: > https://github.com/openjdk/jdk/blob/f080b4bb8a75284db1b6037f8c00ef3b1ef1add1/src/hotspot/cpu/riscv/vm_version_riscv.cpp#L79 > [1] > Link: > https://github.com/golang/go/blob/9e8ea567c838574a0f14538c0bbbd83c3215aa55/src/runtime/tagptr_64bit.go#L47 > [2] > > To: Arnd Bergmann <arnd@...db.de> > To: Richard Henderson <richard.henderson@...aro.org> > To: Ivan Kokshaysky <ink@...assic.park.msu.ru> > To: Matt Turner <mattst88@...il.com> > To: Vineet Gupta <vgupta@...nel.org> > To: Russell King <linux@...linux.org.uk> > To: Guo Ren <guoren@...nel.org> > To: Huacai Chen <chenhuacai@...nel.org> > To: WANG Xuerui <kernel@...0n.name> > To: Thomas Bogendoerfer <tsbogend@...ha.franken.de> > To: James E.J. Bottomley <James.Bottomley@...senPartnership.com> > To: Helge Deller <deller@....de> > To: Michael Ellerman <mpe@...erman.id.au> > To: Nicholas Piggin <npiggin@...il.com> > To: Christophe Leroy <christophe.leroy@...roup.eu> > To: Naveen N Rao <naveen@...nel.org> > To: Alexander Gordeev <agordeev@...ux.ibm.com> > To: Gerald Schaefer <gerald.schaefer@...ux.ibm.com> > To: Heiko Carstens <hca@...ux.ibm.com> > To: Vasily Gorbik <gor@...ux.ibm.com> > To: Christian Borntraeger <borntraeger@...ux.ibm.com> > To: Sven Schnelle <svens@...ux.ibm.com> > To: Yoshinori Sato <ysato@...rs.sourceforge.jp> > To: Rich Felker <dalias@...c.org> > To: John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de> > To: David S. Miller <davem@...emloft.net> > To: Andreas Larsson <andreas@...sler.com> > To: Thomas Gleixner <tglx@...utronix.de> > To: Ingo Molnar <mingo@...hat.com> > To: Borislav Petkov <bp@...en8.de> > To: Dave Hansen <dave.hansen@...ux.intel.com> > To: x86@...nel.org > To: H. Peter Anvin <hpa@...or.com> > To: Andy Lutomirski <luto@...nel.org> > To: Peter Zijlstra <peterz@...radead.org> > To: Muchun Song <muchun.song@...ux.dev> > To: Andrew Morton <akpm@...ux-foundation.org> > To: Liam R. Howlett <Liam.Howlett@...cle.com> > To: Vlastimil Babka <vbabka@...e.cz> > To: Lorenzo Stoakes <lorenzo.stoakes@...cle.com> > To: Shuah Khan <shuah@...nel.org> > To: Christoph Hellwig <hch@...radead.org> > To: Michal Hocko <mhocko@...e.com> > To: "Kirill A. Shutemov" <kirill@...temov.name> > To: Chris Torek <chris.torek@...il.com> > Cc: linux-arch@...r.kernel.org > Cc: linux-kernel@...r.kernel.org > Cc: linux-alpha@...r.kernel.org > Cc: linux-snps-arc@...ts.infradead.org > Cc: linux-arm-kernel@...ts.infradead.org > Cc: linux-csky@...r.kernel.org > Cc: loongarch@...ts.linux.dev > Cc: linux-mips@...r.kernel.org > Cc: linux-parisc@...r.kernel.org > Cc: linuxppc-dev@...ts.ozlabs.org > Cc: linux-s390@...r.kernel.org > Cc: linux-sh@...r.kernel.org > Cc: sparclinux@...r.kernel.org > Cc: linux-mm@...ck.org > Cc: linux-kselftest@...r.kernel.org > Cc: linux-abi-devel@...ts.sourceforge.net > Signed-off-by: Charlie Jenkins <charlie@...osinc.com> > > Changes in v2: > - Added much greater detail to cover letter > - Removed all code that touched architecture specific code and was able > to factor this out into all generic functions, except for flags that > needed to be added to vm_unmapped_area_info > - Made this an RFC since I have only tested it on riscv and x86 > - Link to v1: https://lore.kernel.org/r/20240827-patches-below_hint_mmap-v1-0-46ff2eb9022d@rivosinc.com > > Changes in v3: > - Use a personality flag instead of an mmap flag > - Link to v2: https://lore.kernel.org/r/20240829-patches-below_hint_mmap-v2-0-638a28d9eae0@rivosinc.com > > --- > Charlie Jenkins (2): > mm: Add personality flag to limit address to 47 bits > selftests/mm: Create ADDR_LIMIT_47BIT test > > include/uapi/linux/personality.h | 1 + > mm/mmap.c | 3 ++ > tools/testing/selftests/mm/.gitignore | 1 + > tools/testing/selftests/mm/Makefile | 1 + > tools/testing/selftests/mm/map_47bit_personality.c | 34 ++++++++++++++++++++++ > 5 files changed, 40 insertions(+) > --- > base-commit: 5be63fc19fcaa4c236b307420483578a56986a37 > change-id: 20240827-patches-below_hint_mmap-b13d79ae1c55 > -- > - Charlie > -- Best Regards Guo Ren
Powered by blists - more mailing lists