linux-kernel - [PATCH v2 09/12] powerpc: extend execmem

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: <20230616085038.4121892-10-rppt@kernel.org>
Date:   Fri, 16 Jun 2023 11:50:35 +0300
From:   Mike Rapoport <rppt@...nel.org>
To:     linux-kernel@...r.kernel.org
Cc:     Andrew Morton <akpm@...ux-foundation.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Christophe Leroy <christophe.leroy@...roup.eu>,
        "David S. Miller" <davem@...emloft.net>,
        Dinh Nguyen <dinguyen@...nel.org>,
        Heiko Carstens <hca@...ux.ibm.com>,
        Helge Deller <deller@....de>,
        Huacai Chen <chenhuacai@...nel.org>,
        Kent Overstreet <kent.overstreet@...ux.dev>,
        Luis Chamberlain <mcgrof@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Mike Rapoport <rppt@...nel.org>,
        Nadav Amit <nadav.amit@...il.com>,
        "Naveen N. Rao" <naveen.n.rao@...ux.ibm.com>,
        Palmer Dabbelt <palmer@...belt.com>,
        Puranjay Mohan <puranjay12@...il.com>,
        Rick Edgecombe <rick.p.edgecombe@...el.com>,
        Russell King <linux@...linux.org.uk>,
        Song Liu <song@...nel.org>,
        Steven Rostedt <rostedt@...dmis.org>,
        Thomas Bogendoerfer <tsbogend@...ha.franken.de>,
        Thomas Gleixner <tglx@...utronix.de>,
        Will Deacon <will@...nel.org>, bpf@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-mips@...r.kernel.org,
        linux-mm@...ck.org, linux-modules@...r.kernel.org,
        linux-parisc@...r.kernel.org, linux-riscv@...ts.infradead.org,
        linux-s390@...r.kernel.org, linux-trace-kernel@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org, loongarch@...ts.linux.dev,
        netdev@...r.kernel.org, sparclinux@...r.kernel.org, x86@...nel.org
Subject: [PATCH v2 09/12] powerpc: extend execmem_params for kprobes allocations

From: "Mike Rapoport (IBM)" <rppt@...nel.org>

powerpc overrides kprobes::alloc_insn_page() to remove writable
permissions when STRICT_MODULE_RWX is on.

Add definition of jit area to execmem_params to allow using the generic
kprobes::alloc_insn_page() with the desired permissions.

As powerpc uses breakpoint instructions to inject kprobes, it does not
need to constrain kprobe allocations to the modules area and can use the
entire vmalloc address space.

Signed-off-by: Mike Rapoport (IBM) <rppt@...nel.org>
---
 arch/powerpc/kernel/kprobes.c | 14 --------------
 arch/powerpc/kernel/module.c  | 13 +++++++++++++
 2 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 5db8df5e3657..14c5ddec3056 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -126,20 +126,6 @@ kprobe_opcode_t *arch_adjust_kprobe_addr(unsigned long addr, unsigned long offse
 	return (kprobe_opcode_t *)(addr + offset);
 }
 
-void *alloc_insn_page(void)
-{
-	void *page;
-
-	page = jit_text_alloc(PAGE_SIZE);
-	if (!page)
-		return NULL;
-
-	if (strict_module_rwx_enabled())
-		set_memory_rox((unsigned long)page, 1);
-
-	return page;
-}
-
 int arch_prepare_kprobe(struct kprobe *p)
 {
 	int ret = 0;
diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
index 4c6c15bf3947..8e5b379d6da1 100644
--- a/arch/powerpc/kernel/module.c
+++ b/arch/powerpc/kernel/module.c
@@ -96,6 +96,11 @@ static struct execmem_params execmem_params = {
 			.alignment = 1,
 		},
 	},
+	.jit = {
+		.text = {
+			.alignment = 1,
+		},
+	},
 };
 
 
@@ -131,5 +136,13 @@ struct execmem_params __init *execmem_arch_params(void)
 
 	execmem_params.modules.text.pgprot = prot;
 
+	execmem_params.jit.text.start = VMALLOC_START;
+	execmem_params.jit.text.end = VMALLOC_END;
+
+	if (strict_module_rwx_enabled())
+		execmem_params.jit.text.pgprot = PAGE_KERNEL_ROX;
+	else
+		execmem_params.jit.text.pgprot = PAGE_KERNEL_EXEC;
+
 	return &execmem_params;
 }
-- 
2.35.1