linux-kernel - [RFC V2 5/8] powerpc: add exit_flags field in pt

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]

Message-ID: <20250908210235.137300-8-mchauras@linux.ibm.com>
Date: Tue,  9 Sep 2025 02:32:34 +0530
From: Mukesh Kumar Chaurasiya <mchauras@...ux.ibm.com>
To: maddy@...ux.ibm.com, mpe@...erman.id.au, npiggin@...il.com,
        christophe.leroy@...roup.eu, oleg@...hat.com, kees@...nel.org,
        luto@...capital.net, wad@...omium.org, mchauras@...ux.ibm.com,
        deller@....de, ldv@...ace.io, macro@...am.me.uk, charlie@...osinc.com,
        akpm@...ux-foundation.org, bigeasy@...utronix.de,
        ankur.a.arora@...cle.com, sshegde@...ux.ibm.com, naveen@...nel.org,
        thomas.weissschuh@...utronix.de, Jason@...c4.com, peterz@...radead.org,
        tglx@...utronix.de, namcao@...utronix.de, kan.liang@...ux.intel.com,
        mingo@...nel.org, oliver.upton@...ux.dev, mark.barnett@....com,
        atrajeev@...ux.vnet.ibm.com, rppt@...nel.org, coltonlewis@...gle.com,
        linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org
Subject: [RFC V2 5/8] powerpc: add exit_flags field in pt_regs

Add field exit_flags in the pt_regs. This will hold the flags while
executing interrupt or syscall which is required during exit to user.

Signed-off-by: Mukesh Kumar Chaurasiya <mchauras@...ux.ibm.com>
---
 arch/powerpc/include/asm/ptrace.h      |  2 ++
 arch/powerpc/include/uapi/asm/ptrace.h | 14 +++++++++-----
 arch/powerpc/kernel/asm-offsets.c      |  1 +
 arch/powerpc/kernel/ptrace/ptrace.c    |  1 +
 4 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index 7b9350756875a..1b0ad5088f60d 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -53,6 +53,8 @@ struct pt_regs
 				unsigned long esr;
 			};
 			unsigned long result;
+			unsigned long exit_flags;
+			unsigned long __pt_regs_pad[1];	/* Maintain 16 byte interrupt stack alignment */
 		};
 	};
 #if defined(CONFIG_PPC64) || defined(CONFIG_PPC_KUAP)
diff --git a/arch/powerpc/include/uapi/asm/ptrace.h b/arch/powerpc/include/uapi/asm/ptrace.h
index 7004cfea3f5ff..4de612e2e40ac 100644
--- a/arch/powerpc/include/uapi/asm/ptrace.h
+++ b/arch/powerpc/include/uapi/asm/ptrace.h
@@ -55,6 +55,8 @@ struct pt_regs
 	unsigned long dar;		/* Fault registers */
 	unsigned long dsisr;		/* on 4xx/Book-E used for ESR */
 	unsigned long result;		/* Result of a system call */
+	unsigned long exit_flags;	/* System call exit flags */
+	unsigned long __pt_regs_pad[1];	/* Maintain 16 byte interrupt stack alignment */
 };
 
 #endif /* __ASSEMBLY__ */
@@ -114,10 +116,12 @@ struct pt_regs
 #define PT_DAR	41
 #define PT_DSISR 42
 #define PT_RESULT 43
-#define PT_DSCR 44
-#define PT_REGS_COUNT 44
+#define PT_EXIT_FLAGS 44
+#define PT_PAD 45
+#define PT_DSCR 46
+#define PT_REGS_COUNT 46
 
-#define PT_FPR0	48	/* each FP reg occupies 2 slots in this space */
+#define PT_FPR0	(PT_REGS_COUNT + 4)	/* each FP reg occupies 2 slots in this space */
 
 #ifndef __powerpc64__
 
@@ -129,7 +133,7 @@ struct pt_regs
 #define PT_FPSCR (PT_FPR0 + 32)	/* each FP reg occupies 1 slot in 64-bit space */
 
 
-#define PT_VR0 82	/* each Vector reg occupies 2 slots in 64-bit */
+#define PT_VR0	(PT_FPSCR + 2)	/* <82> each Vector reg occupies 2 slots in 64-bit */
 #define PT_VSCR (PT_VR0 + 32*2 + 1)
 #define PT_VRSAVE (PT_VR0 + 33*2)
 
@@ -137,7 +141,7 @@ struct pt_regs
 /*
  * Only store first 32 VSRs here. The second 32 VSRs in VR0-31
  */
-#define PT_VSR0 150	/* each VSR reg occupies 2 slots in 64-bit */
+#define PT_VSR0	(PT_VRSAVE + 2)	/* each VSR reg occupies 2 slots in 64-bit */
 #define PT_VSR31 (PT_VSR0 + 2*31)
 #endif /* __powerpc64__ */
 
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index b3048f6d3822c..4d4e880e3c616 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -291,6 +291,7 @@ int main(void)
 	STACK_PT_REGS_OFFSET(_ESR, esr);
 	STACK_PT_REGS_OFFSET(ORIG_GPR3, orig_gpr3);
 	STACK_PT_REGS_OFFSET(RESULT, result);
+	STACK_PT_REGS_OFFSET(EXIT_FLAGS, exit_flags);
 	STACK_PT_REGS_OFFSET(_TRAP, trap);
 #ifdef CONFIG_PPC64
 	STACK_PT_REGS_OFFSET(SOFTE, softe);
diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c
index c6997df632873..2134b6d155ff6 100644
--- a/arch/powerpc/kernel/ptrace/ptrace.c
+++ b/arch/powerpc/kernel/ptrace/ptrace.c
@@ -432,6 +432,7 @@ void __init pt_regs_check(void)
 	CHECK_REG(PT_DAR, dar);
 	CHECK_REG(PT_DSISR, dsisr);
 	CHECK_REG(PT_RESULT, result);
+	CHECK_REG(PT_EXIT_FLAGS, exit_flags);
 	#undef CHECK_REG
 
 	BUILD_BUG_ON(PT_REGS_COUNT != sizeof(struct user_pt_regs) / sizeof(unsigned long));
-- 
2.51.0