linux-kernel - [RFC PATCH v1 06/28] riscv: zicfiss/zicfilp extension csr and bit definitions

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Wed, 24 Jan 2024 22:21:31 -0800
From: debug@...osinc.com
To: rick.p.edgecombe@...el.com,
	broonie@...nel.org,
	Szabolcs.Nagy@....com,
	kito.cheng@...ive.com,
	keescook@...omium.org,
	ajones@...tanamicro.com,
	paul.walmsley@...ive.com,
	palmer@...belt.com,
	conor.dooley@...rochip.com,
	cleger@...osinc.com,
	atishp@...shpatra.org,
	alex@...ti.fr,
	bjorn@...osinc.com,
	alexghiti@...osinc.com
Cc: corbet@....net,
	aou@...s.berkeley.edu,
	oleg@...hat.com,
	akpm@...ux-foundation.org,
	arnd@...db.de,
	ebiederm@...ssion.com,
	shuah@...nel.org,
	brauner@...nel.org,
	debug@...osinc.com,
	guoren@...nel.org,
	samitolvanen@...gle.com,
	evan@...osinc.com,
	xiao.w.wang@...el.com,
	apatel@...tanamicro.com,
	mchitale@...tanamicro.com,
	waylingii@...il.com,
	greentime.hu@...ive.com,
	heiko@...ech.de,
	jszhang@...nel.org,
	shikemeng@...weicloud.com,
	david@...hat.com,
	charlie@...osinc.com,
	panqinglin2020@...as.ac.cn,
	willy@...radead.org,
	vincent.chen@...ive.com,
	andy.chiu@...ive.com,
	gerg@...nel.org,
	jeeheng.sia@...rfivetech.com,
	mason.huo@...rfivetech.com,
	ancientmodern4@...il.com,
	mathis.salmen@...sal.de,
	cuiyunhui@...edance.com,
	bhe@...hat.com,
	chenjiahao16@...wei.com,
	ruscur@...sell.cc,
	bgray@...ux.ibm.com,
	alx@...nel.org,
	baruch@...s.co.il,
	zhangqing@...ngson.cn,
	catalin.marinas@....com,
	revest@...omium.org,
	josh@...htriplett.org,
	joey.gouly@....com,
	shr@...kernel.io,
	omosnace@...hat.com,
	ojeda@...nel.org,
	jhubbard@...dia.com,
	linux-doc@...r.kernel.org,
	linux-riscv@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	linux-mm@...ck.org,
	linux-arch@...r.kernel.org,
	linux-kselftest@...r.kernel.org
Subject: [RFC PATCH v1 06/28] riscv: zicfiss/zicfilp extension csr and bit definitions

From: Deepak Gupta <debug@...osinc.com>

zicfiss and zicfilp extension gets enabled via b3 and b2 in xenvcfg CSR.
menvcfg controls enabling for S/HS mode. henvcfg control enabling for VS while
senvcfg controls enabling for U/VU mode.

zicfilp extension extends xstatus CSR to hold `expected landing pad` bit.
A trap or interrupt can occur between an indirect jmp/call and target instr.
`expected landing pad` bit from CPU is recorded into xstatus CSR so that when
supervisor performs xret, `expected landing pad` state of CPU can be restored.

zicfiss adds one new CSR
- CSR_SSP: CSR_SSP contains current shadow stack pointer.

Signed-off-by: Deepak Gupta <debug@...osinc.com>
---
 arch/riscv/include/asm/csr.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 01ba87954da2..80fe38d5de4a 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -18,6 +18,15 @@
 #define SR_MPP		_AC(0x00001800, UL) /* Previously Machine */
 #define SR_SUM		_AC(0x00040000, UL) /* Supervisor User Memory Access */
 
+/* zicfilp landing pad status bit */
+#define SR_SPELP	_AC(0x00800000, UL)
+#define SR_MPELP	_AC(0x020000000000, UL)
+#ifdef CONFIG_RISCV_M_MODE
+#define SR_ELP		SR_MPELP
+#else
+#define SR_ELP		SR_SPELP
+#endif
+
 #define SR_FS		_AC(0x00006000, UL) /* Floating-point Status */
 #define SR_FS_OFF	_AC(0x00000000, UL)
 #define SR_FS_INITIAL	_AC(0x00002000, UL)
@@ -196,6 +205,8 @@
 #define ENVCFG_PBMTE			(_AC(1, ULL) << 62)
 #define ENVCFG_CBZE			(_AC(1, UL) << 7)
 #define ENVCFG_CBCFE			(_AC(1, UL) << 6)
+#define ENVCFG_LPE			(_AC(1, UL) << 2)
+#define ENVCFG_SSE			(_AC(1, UL) << 3)
 #define ENVCFG_CBIE_SHIFT		4
 #define ENVCFG_CBIE			(_AC(0x3, UL) << ENVCFG_CBIE_SHIFT)
 #define ENVCFG_CBIE_ILL			_AC(0x0, UL)
@@ -216,6 +227,11 @@
 #define SMSTATEEN0_HSENVCFG		(_ULL(1) << SMSTATEEN0_HSENVCFG_SHIFT)
 #define SMSTATEEN0_SSTATEEN0_SHIFT	63
 #define SMSTATEEN0_SSTATEEN0		(_ULL(1) << SMSTATEEN0_SSTATEEN0_SHIFT)
+/*
+ * zicfiss user mode csr
+ * CSR_SSP holds current shadow stack pointer.
+ */
+#define CSR_SSP                 0x011
 
 /* symbolic CSR names: */
 #define CSR_CYCLE		0xc00
-- 
2.43.0