From e312d7a74924d6e3880fa27adb4bcd04c8c25983 Mon Sep 17 00:00:00 2001
From: Jiajie Li <lijiajie11@huawei.com>
Date: Mon, 12 Oct 2020 16:30:58 +0800
Subject: [PATCH 41/89] kpatch_ptrace: Split function
 kpatch_execute_remote_func

The function kpatch_execute_remote_func is arch related, first
rename it with kpatch_arch_execute_remote_func, and the make separate
definations in arch/x86/arch_ptrace.c and arch/aarch64/arch_ptrace.c

Signed-off-by: Jiajie Li <lijiajie11@huawei.com>
Signed-off-by: Ying Fang <fangying1@huawei.com>
---
 src/arch/aarch64/arch_ptrace.c | 87 ++++++++++++++++++++++++++++++++++
 src/arch/x86/arch_ptrace.c     | 79 ++++++++++++++++++++++++++++++
 src/include/kpatch_ptrace.h    |  9 ++++
 src/kpatch_ptrace.c            | 82 +-------------------------------
 4 files changed, 176 insertions(+), 81 deletions(-)

diff --git a/src/arch/aarch64/arch_ptrace.c b/src/arch/aarch64/arch_ptrace.c
index 0366d4f..821b4e8 100644
--- a/src/arch/aarch64/arch_ptrace.c
+++ b/src/arch/aarch64/arch_ptrace.c
@@ -22,6 +22,93 @@
 
 #include <gelf.h>
 
+int
+kpatch_arch_execute_remote_func(struct kpatch_ptrace_ctx *pctx,
+			   const unsigned char *code,
+			   size_t codelen,
+			   struct user_regs_struct *pregs,
+			   int (*func)(struct kpatch_ptrace_ctx *pctx,
+				       void *data),
+			   void *data)
+{
+	struct user_regs_struct orig_regs, regs;
+	struct iovec orig_regs_iov, regs_iov;
+
+	orig_regs_iov.iov_base = &orig_regs;
+	orig_regs_iov.iov_len = sizeof(orig_regs);
+	regs_iov.iov_base = &regs;
+	regs_iov.iov_len = sizeof(regs);
+
+	unsigned char orig_code[codelen];
+	int ret;
+	kpatch_process_t *proc = pctx->proc;
+	unsigned long libc_base = proc->libc_base;
+
+
+	ret = ptrace(PTRACE_GETREGSET, pctx->pid, (void*)NT_PRSTATUS, (void*)&orig_regs_iov);
+	if (ret < 0) {
+		kplogerror("can't get regs - %d\n", pctx->pid);
+		return -1;
+	}
+	ret = kpatch_process_mem_read(
+			      proc,
+			      libc_base,
+			      (unsigned long *)orig_code,
+			      codelen);
+	if (ret < 0) {
+		kplogerror("can't peek original code - %d\n", pctx->pid);
+		return -1;
+	}
+	ret = kpatch_process_mem_write(
+			      proc,
+			      (unsigned long *)code,
+			      libc_base,
+			      codelen);
+	if (ret < 0) {
+		kplogerror("can't poke syscall code - %d\n", pctx->pid);
+		goto poke_back;
+	}
+
+	regs = orig_regs;
+	regs.pc = libc_base;
+
+	copy_regs(&regs, pregs);
+
+	ret = ptrace(PTRACE_SETREGSET, pctx->pid, (void*)NT_PRSTATUS, (void*)&regs_iov);
+	if (ret < 0) {
+		kplogerror("can't set regs - %d\n", pctx->pid);
+		goto poke_back;
+	}
+
+	ret = func(pctx, data);
+	if (ret < 0) {
+		kplogerror("failed call to func\n");
+		goto poke_back;
+	}
+
+	ret = ptrace(PTRACE_GETREGSET, pctx->pid, (void*)NT_PRSTATUS, (void*)&regs_iov);
+	if (ret < 0) {
+		kplogerror("can't get updated regs - %d\n", pctx->pid);
+		goto poke_back;
+	}
+
+	ret = ptrace(PTRACE_SETREGSET, pctx->pid, (void*)NT_PRSTATUS, (void*)&orig_regs_iov);
+	if (ret < 0) {
+		kplogerror("can't restore regs - %d\n", pctx->pid);
+		goto poke_back;
+	}
+
+	*pregs = regs;
+
+poke_back:
+	kpatch_process_mem_write(
+			proc,
+			(unsigned long *)orig_code,
+			libc_base,
+			codelen);
+	return ret;
+}
+
 void copy_regs(struct user_regs_struct *dst,
 		      struct user_regs_struct *src)
 {
diff --git a/src/arch/x86/arch_ptrace.c b/src/arch/x86/arch_ptrace.c
index fa23757..9239f52 100644
--- a/src/arch/x86/arch_ptrace.c
+++ b/src/arch/x86/arch_ptrace.c
@@ -22,6 +22,85 @@
 
 #include <gelf.h>
 
+int
+kpatch_arch_execute_remote_func(struct kpatch_ptrace_ctx *pctx,
+			   const unsigned char *code,
+			   size_t codelen,
+			   struct user_regs_struct *pregs,
+			   int (*func)(struct kpatch_ptrace_ctx *pctx,
+				       void *data),
+			   void *data)
+{
+	struct user_regs_struct orig_regs, regs;
+	unsigned char orig_code[codelen];
+	int ret;
+	kpatch_process_t *proc = pctx->proc;
+	unsigned long libc_base = proc->libc_base;
+
+	ret = ptrace(PTRACE_GETREGS, pctx->pid, NULL, &orig_regs);
+	if (ret < 0) {
+		kplogerror("can't get regs - %d\n", pctx->pid);
+		return -1;
+	}
+	ret = kpatch_process_mem_read(
+			      proc,
+			      libc_base,
+			      (unsigned long *)orig_code,
+			      codelen);
+	if (ret < 0) {
+		kplogerror("can't peek original code - %d\n", pctx->pid);
+		return -1;
+	}
+	ret = kpatch_process_mem_write(
+			      proc,
+			      (unsigned long *)code,
+			      libc_base,
+			      codelen);
+	if (ret < 0) {
+		kplogerror("can't poke syscall code - %d\n", pctx->pid);
+		goto poke_back;
+	}
+
+	regs = orig_regs;
+	regs.rip = libc_base;
+
+	copy_regs(&regs, pregs);
+
+	ret = ptrace(PTRACE_SETREGS, pctx->pid, NULL, &regs);
+	if (ret < 0) {
+		kplogerror("can't set regs - %d\n", pctx->pid);
+		goto poke_back;
+	}
+
+	ret = func(pctx, data);
+	if (ret < 0) {
+		kplogerror("failed call to func\n");
+		goto poke_back;
+	}
+
+	ret = ptrace(PTRACE_GETREGS, pctx->pid, NULL, &regs);
+	if (ret < 0) {
+		kplogerror("can't get updated regs - %d\n", pctx->pid);
+		goto poke_back;
+	}
+
+	ret = ptrace(PTRACE_SETREGS, pctx->pid, NULL, &orig_regs);
+	if (ret < 0) {
+		kplogerror("can't restore regs - %d\n", pctx->pid);
+		goto poke_back;
+	}
+
+	*pregs = regs;
+
+poke_back:
+	kpatch_process_mem_write(
+			proc,
+			(unsigned long *)orig_code,
+			libc_base,
+			codelen);
+	return ret;
+}
+
 void copy_regs(struct user_regs_struct *dst,
 		      struct user_regs_struct *src)
 {
diff --git a/src/include/kpatch_ptrace.h b/src/include/kpatch_ptrace.h
index e434d68..f35aabd 100644
--- a/src/include/kpatch_ptrace.h
+++ b/src/include/kpatch_ptrace.h
@@ -125,4 +125,13 @@ kpatch_arch_ptrace_waitpid(kpatch_process_t *proc,
 void copy_regs(struct user_regs_struct *dst,
 		      struct user_regs_struct *src);
 
+int
+kpatch_arch_execute_remote_func(struct kpatch_ptrace_ctx *pctx,
+			   const unsigned char *code,
+			   size_t codelen,
+			   struct user_regs_struct *pregs,
+			   int (*func)(struct kpatch_ptrace_ctx *pctx,
+				       void *data),
+			   void *data);
+
 #endif
diff --git a/src/kpatch_ptrace.c b/src/kpatch_ptrace.c
index 180bbaa..9056815 100644
--- a/src/kpatch_ptrace.c
+++ b/src/kpatch_ptrace.c
@@ -413,86 +413,6 @@ poke_back:
 	return ret;
 }
 
-static
-int
-kpatch_execute_remote_func(struct kpatch_ptrace_ctx *pctx,
-			   const unsigned char *code,
-			   size_t codelen,
-			   struct user_regs_struct *pregs,
-			   int (*func)(struct kpatch_ptrace_ctx *pctx,
-				       void *data),
-			   void *data)
-{
-	struct user_regs_struct orig_regs, regs;
-	unsigned char orig_code[codelen];
-	int ret;
-	kpatch_process_t *proc = pctx->proc;
-	unsigned long libc_base = proc->libc_base;
-
-	ret = ptrace(PTRACE_GETREGS, pctx->pid, NULL, &orig_regs);
-	if (ret < 0) {
-		kplogerror("can't get regs - %d\n", pctx->pid);
-		return -1;
-	}
-	ret = kpatch_process_mem_read(
-			      proc,
-			      libc_base,
-			      (unsigned long *)orig_code,
-			      codelen);
-	if (ret < 0) {
-		kplogerror("can't peek original code - %d\n", pctx->pid);
-		return -1;
-	}
-	ret = kpatch_process_mem_write(
-			      proc,
-			      (unsigned long *)code,
-			      libc_base,
-			      codelen);
-	if (ret < 0) {
-		kplogerror("can't poke syscall code - %d\n", pctx->pid);
-		goto poke_back;
-	}
-
-	regs = orig_regs;
-	regs.rip = libc_base;
-
-	copy_regs(&regs, pregs);
-
-	ret = ptrace(PTRACE_SETREGS, pctx->pid, NULL, &regs);
-	if (ret < 0) {
-		kplogerror("can't set regs - %d\n", pctx->pid);
-		goto poke_back;
-	}
-
-	ret = func(pctx, data);
-	if (ret < 0) {
-		kplogerror("failed call to func\n");
-		goto poke_back;
-	}
-
-	ret = ptrace(PTRACE_GETREGS, pctx->pid, NULL, &regs);
-	if (ret < 0) {
-		kplogerror("can't get updated regs - %d\n", pctx->pid);
-		goto poke_back;
-	}
-
-	ret = ptrace(PTRACE_SETREGS, pctx->pid, NULL, &orig_regs);
-	if (ret < 0) {
-		kplogerror("can't restore regs - %d\n", pctx->pid);
-		goto poke_back;
-	}
-
-	*pregs = regs;
-
-poke_back:
-	kpatch_process_mem_write(
-			proc,
-			(unsigned long *)orig_code,
-			libc_base,
-			codelen);
-	return ret;
-}
-
 static int
 wait_for_stop(struct kpatch_ptrace_ctx *pctx,
 	      void *data)
@@ -592,7 +512,7 @@ kpatch_execute_remote(struct kpatch_ptrace_ctx *pctx,
 		      size_t codelen,
 		      struct user_regs_struct *pregs)
 {
-	return kpatch_execute_remote_func(pctx,
+	return kpatch_arch_execute_remote_func(pctx,
 					  code,
 					  codelen,
 					  pregs,
-- 
2.23.0