From: Anders Roxell <anders.roxell@linaro.org> To: catalin.marinas@arm.com, will.deacon@arm.com Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Anders Roxell <anders.roxell@linaro.org>, Arnd Bergmann <arnd@arndb.de>, Ard Biesheuvel <ard.biesheuvel@linaro.org>, Laura Abbott <labbott@redhat.com> Subject: [PATCH] arm64: kprobe: make page to RO mode when allocate it Date: Mon, 15 Oct 2018 13:16:00 +0200 [thread overview] Message-ID: <20181015111600.5479-1-anders.roxell@linaro.org> (raw) Commit 1404d6f13e47 ("arm64: dump: Add checking for writable and exectuable pages") has successfully identified code that leaves a page with W+X permissions. [ 3.245140] arm64/mm: Found insecure W+X mapping at address (____ptrval____)/0xffff000000d90000 [ 3.245771] WARNING: CPU: 0 PID: 1 at ../arch/arm64/mm/dump.c:232 note_page+0x410/0x420 [ 3.246141] Modules linked in: [ 3.246653] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5-next-20180928-00001-ge70ae259b853-dirty #62 [ 3.247008] Hardware name: linux,dummy-virt (DT) [ 3.247347] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 3.247623] pc : note_page+0x410/0x420 [ 3.247898] lr : note_page+0x410/0x420 [ 3.248071] sp : ffff00000804bcd0 [ 3.248254] x29: ffff00000804bcd0 x28: ffff000009274000 [ 3.248578] x27: ffff00000921a000 x26: ffff80007dfff000 [ 3.248845] x25: ffff0000093f5000 x24: ffff000009526f6a [ 3.249109] x23: 0000000000000004 x22: ffff000000d91000 [ 3.249396] x21: ffff000000d90000 x20: 0000000000000000 [ 3.249661] x19: ffff00000804bde8 x18: 0000000000000400 [ 3.249924] x17: 0000000000000000 x16: 0000000000000000 [ 3.250271] x15: ffffffffffffffff x14: 295f5f5f5f6c6176 [ 3.250594] x13: 7274705f5f5f5f28 x12: 2073736572646461 [ 3.250941] x11: 20746120676e6970 x10: 70616d20582b5720 [ 3.251252] x9 : 6572756365736e69 x8 : 3039643030303030 [ 3.251519] x7 : 306666666678302f x6 : ffff0000095467b2 [ 3.251802] x5 : 0000000000000000 x4 : 0000000000000000 [ 3.252060] x3 : 0000000000000000 x2 : ffffffffffffffff [ 3.252323] x1 : 4d151327adc50b00 x0 : 0000000000000000 [ 3.252664] Call trace: [ 3.252953] note_page+0x410/0x420 [ 3.253186] walk_pgd+0x12c/0x238 [ 3.253417] ptdump_check_wx+0x68/0xf8 [ 3.253637] mark_rodata_ro+0x68/0x98 [ 3.253847] kernel_init+0x38/0x160 [ 3.254103] ret_from_fork+0x10/0x18 Reworked to that when allocate a page it sets mode RO. Inspired by commit 63fef14fc98a ("kprobes/x86: Make insn buffer always ROX and use text_poke()"). Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Co-developed-by: Arnd Bergmann <arnd@arndb.de> Co-developed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> --- arch/arm64/kernel/probes/kprobes.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index 9b65132e789a..b842e908b423 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -23,7 +23,9 @@ #include <linux/slab.h> #include <linux/stop_machine.h> #include <linux/sched/debug.h> +#include <linux/set_memory.h> #include <linux/stringify.h> +#include <linux/vmalloc.h> #include <asm/traps.h> #include <asm/ptrace.h> #include <asm/cacheflush.h> @@ -42,10 +44,21 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); static void __kprobes post_kprobe_handler(struct kprobe_ctlblk *, struct pt_regs *); +static int __kprobes patch_text(kprobe_opcode_t *addr, u32 opcode) +{ + void *addrs[1]; + u32 insns[1]; + + addrs[0] = (void *)addr; + insns[0] = (u32)opcode; + + return aarch64_insn_patch_text(addrs, insns, 1); +} + static void __kprobes arch_prepare_ss_slot(struct kprobe *p) { /* prepare insn slot */ - p->ainsn.api.insn[0] = cpu_to_le32(p->opcode); + patch_text(p->ainsn.api.insn, p->opcode); flush_icache_range((uintptr_t) (p->ainsn.api.insn), (uintptr_t) (p->ainsn.api.insn) + @@ -118,15 +131,15 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) return 0; } -static int __kprobes patch_text(kprobe_opcode_t *addr, u32 opcode) +void *alloc_insn_page(void) { - void *addrs[1]; - u32 insns[1]; + void *page; - addrs[0] = (void *)addr; - insns[0] = (u32)opcode; + page = vmalloc_exec(PAGE_SIZE); + if (page) + set_memory_ro((unsigned long)page & PAGE_MASK, 1); - return aarch64_insn_patch_text(addrs, insns, 1); + return page; } /* arm kprobe: install breakpoint in text */ -- 2.19.1
WARNING: multiple messages have this Message-ID (diff)
From: anders.roxell@linaro.org (Anders Roxell) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH] arm64: kprobe: make page to RO mode when allocate it Date: Mon, 15 Oct 2018 13:16:00 +0200 [thread overview] Message-ID: <20181015111600.5479-1-anders.roxell@linaro.org> (raw) Commit 1404d6f13e47 ("arm64: dump: Add checking for writable and exectuable pages") has successfully identified code that leaves a page with W+X permissions. [ 3.245140] arm64/mm: Found insecure W+X mapping at address (____ptrval____)/0xffff000000d90000 [ 3.245771] WARNING: CPU: 0 PID: 1 at ../arch/arm64/mm/dump.c:232 note_page+0x410/0x420 [ 3.246141] Modules linked in: [ 3.246653] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5-next-20180928-00001-ge70ae259b853-dirty #62 [ 3.247008] Hardware name: linux,dummy-virt (DT) [ 3.247347] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 3.247623] pc : note_page+0x410/0x420 [ 3.247898] lr : note_page+0x410/0x420 [ 3.248071] sp : ffff00000804bcd0 [ 3.248254] x29: ffff00000804bcd0 x28: ffff000009274000 [ 3.248578] x27: ffff00000921a000 x26: ffff80007dfff000 [ 3.248845] x25: ffff0000093f5000 x24: ffff000009526f6a [ 3.249109] x23: 0000000000000004 x22: ffff000000d91000 [ 3.249396] x21: ffff000000d90000 x20: 0000000000000000 [ 3.249661] x19: ffff00000804bde8 x18: 0000000000000400 [ 3.249924] x17: 0000000000000000 x16: 0000000000000000 [ 3.250271] x15: ffffffffffffffff x14: 295f5f5f5f6c6176 [ 3.250594] x13: 7274705f5f5f5f28 x12: 2073736572646461 [ 3.250941] x11: 20746120676e6970 x10: 70616d20582b5720 [ 3.251252] x9 : 6572756365736e69 x8 : 3039643030303030 [ 3.251519] x7 : 306666666678302f x6 : ffff0000095467b2 [ 3.251802] x5 : 0000000000000000 x4 : 0000000000000000 [ 3.252060] x3 : 0000000000000000 x2 : ffffffffffffffff [ 3.252323] x1 : 4d151327adc50b00 x0 : 0000000000000000 [ 3.252664] Call trace: [ 3.252953] note_page+0x410/0x420 [ 3.253186] walk_pgd+0x12c/0x238 [ 3.253417] ptdump_check_wx+0x68/0xf8 [ 3.253637] mark_rodata_ro+0x68/0x98 [ 3.253847] kernel_init+0x38/0x160 [ 3.254103] ret_from_fork+0x10/0x18 Reworked to that when allocate a page it sets mode RO. Inspired by commit 63fef14fc98a ("kprobes/x86: Make insn buffer always ROX and use text_poke()"). Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Co-developed-by: Arnd Bergmann <arnd@arndb.de> Co-developed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> --- arch/arm64/kernel/probes/kprobes.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index 9b65132e789a..b842e908b423 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -23,7 +23,9 @@ #include <linux/slab.h> #include <linux/stop_machine.h> #include <linux/sched/debug.h> +#include <linux/set_memory.h> #include <linux/stringify.h> +#include <linux/vmalloc.h> #include <asm/traps.h> #include <asm/ptrace.h> #include <asm/cacheflush.h> @@ -42,10 +44,21 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); static void __kprobes post_kprobe_handler(struct kprobe_ctlblk *, struct pt_regs *); +static int __kprobes patch_text(kprobe_opcode_t *addr, u32 opcode) +{ + void *addrs[1]; + u32 insns[1]; + + addrs[0] = (void *)addr; + insns[0] = (u32)opcode; + + return aarch64_insn_patch_text(addrs, insns, 1); +} + static void __kprobes arch_prepare_ss_slot(struct kprobe *p) { /* prepare insn slot */ - p->ainsn.api.insn[0] = cpu_to_le32(p->opcode); + patch_text(p->ainsn.api.insn, p->opcode); flush_icache_range((uintptr_t) (p->ainsn.api.insn), (uintptr_t) (p->ainsn.api.insn) + @@ -118,15 +131,15 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) return 0; } -static int __kprobes patch_text(kprobe_opcode_t *addr, u32 opcode) +void *alloc_insn_page(void) { - void *addrs[1]; - u32 insns[1]; + void *page; - addrs[0] = (void *)addr; - insns[0] = (u32)opcode; + page = vmalloc_exec(PAGE_SIZE); + if (page) + set_memory_ro((unsigned long)page & PAGE_MASK, 1); - return aarch64_insn_patch_text(addrs, insns, 1); + return page; } /* arm kprobe: install breakpoint in text */ -- 2.19.1
next reply other threads:[~2018-10-15 11:16 UTC|newest] Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-10-15 11:16 Anders Roxell [this message] 2018-10-15 11:16 ` [PATCH] arm64: kprobe: make page to RO mode when allocate it Anders Roxell 2018-10-15 11:22 ` Ard Biesheuvel 2018-10-15 11:22 ` Ard Biesheuvel 2018-10-15 12:27 ` Masami Hiramatsu 2018-10-15 12:27 ` Masami Hiramatsu 2018-10-22 10:56 ` Laura Abbott 2018-10-22 10:56 ` Laura Abbott 2018-10-29 12:04 ` Will Deacon 2018-10-29 12:04 ` Will Deacon 2018-10-29 12:11 ` Arnd Bergmann 2018-10-29 12:11 ` Arnd Bergmann 2018-10-29 17:02 ` Will Deacon 2018-10-29 17:02 ` Will Deacon
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20181015111600.5479-1-anders.roxell@linaro.org \ --to=anders.roxell@linaro.org \ --cc=ard.biesheuvel@linaro.org \ --cc=arnd@arndb.de \ --cc=catalin.marinas@arm.com \ --cc=labbott@redhat.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=will.deacon@arm.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.