6 files changed, 35 insertions, 9 deletions

diff --git a/arch/riscv/kernel/kgdb.c b/arch/riscv/kernel/kgdb.c
index 9f3db3503dab..15fec5d1e6de 100644
--- a/arch/riscv/kernel/kgdb.c
+++ b/arch/riscv/kernel/kgdb.c
@@ -265,10 +265,10 @@ void kgdb_arch_handle_qxfer_pkt(char *remcom_in_buffer,
 {
 	if (!strncmp(remcom_in_buffer, gdb_xfer_read_target,
 		     sizeof(gdb_xfer_read_target)))
-		strcpy(remcom_out_buffer, riscv_gdb_stub_target_desc);
+		strscpy(remcom_out_buffer, riscv_gdb_stub_target_desc, BUFMAX);
 	else if (!strncmp(remcom_in_buffer, gdb_xfer_read_cpuxml,
 			  sizeof(gdb_xfer_read_cpuxml)))
-		strcpy(remcom_out_buffer, riscv_gdb_stub_cpuxml);
+		strscpy(remcom_out_buffer, riscv_gdb_stub_cpuxml, BUFMAX);
 }
 
 static inline void kgdb_arch_update_addr(struct pt_regs *regs,
diff --git a/arch/riscv/kernel/module-sections.c b/arch/riscv/kernel/module-sections.c
index 75551ac6504c..1675cbad8619 100644
--- a/arch/riscv/kernel/module-sections.c
+++ b/arch/riscv/kernel/module-sections.c
@@ -119,6 +119,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 	unsigned int num_plts = 0;
 	unsigned int num_gots = 0;
 	Elf_Rela *scratch = NULL;
+	Elf_Rela *new_scratch;
 	size_t scratch_size = 0;
 	int i;
 
@@ -168,9 +169,12 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 		scratch_size_needed = (num_scratch_relas + num_relas) * sizeof(*scratch);
 		if (scratch_size_needed > scratch_size) {
 			scratch_size = scratch_size_needed;
-			scratch = kvrealloc(scratch, scratch_size, GFP_KERNEL);
-			if (!scratch)
+			new_scratch = kvrealloc(scratch, scratch_size, GFP_KERNEL);
+			if (!new_scratch) {
+				kvfree(scratch);
 				return -ENOMEM;
+			}
+			scratch = new_scratch;
 		}
 
 		for (size_t j = 0; j < num_relas; j++)
diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
index 3fe9e6edef8f..b41b6255751c 100644
--- a/arch/riscv/kernel/stacktrace.c
+++ b/arch/riscv/kernel/stacktrace.c
@@ -16,6 +16,22 @@
 
 #ifdef CONFIG_FRAME_POINTER
 
+/*
+ * This disables KASAN checking when reading a value from another task's stack,
+ * since the other task could be running on another CPU and could have poisoned
+ * the stack in the meantime.
+ */
+#define READ_ONCE_TASK_STACK(task, x)			\
+({							\
+	unsigned long val;				\
+	unsigned long addr = x;				\
+	if ((task) == current)				\
+		val = READ_ONCE(addr);			\
+	else						\
+		val = READ_ONCE_NOCHECK(addr);		\
+	val;						\
+})
+
 extern asmlinkage void handle_exception(void);
 extern unsigned long ret_from_exception_end;
 
@@ -69,8 +85,9 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs,
 			fp = frame->ra;
 			pc = regs->ra;
 		} else {
-			fp = frame->fp;
-			pc = ftrace_graph_ret_addr(current, &graph_idx, frame->ra,
+			fp = READ_ONCE_TASK_STACK(task, frame->fp);
+			pc = READ_ONCE_TASK_STACK(task, frame->ra);
+			pc = ftrace_graph_ret_addr(current, &graph_idx, pc,
 						   &frame->ra);
 			if (pc >= (unsigned long)handle_exception &&
 			    pc < (unsigned long)&ret_from_exception_end) {
diff --git a/arch/riscv/kernel/tests/Kconfig.debug b/arch/riscv/kernel/tests/Kconfig.debug
index 5db4df44279e..40f8dafffa0a 100644
--- a/arch/riscv/kernel/tests/Kconfig.debug
+++ b/arch/riscv/kernel/tests/Kconfig.debug
@@ -31,7 +31,7 @@ config RISCV_MODULE_LINKING_KUNIT
          If unsure, say N.
 
 config RISCV_KPROBES_KUNIT
-       bool "KUnit test for riscv kprobes" if !KUNIT_ALL_TESTS
+       tristate "KUnit test for riscv kprobes" if !KUNIT_ALL_TESTS
        depends on KUNIT
        depends on KPROBES
        default KUNIT_ALL_TESTS
diff --git a/arch/riscv/kernel/tests/kprobes/Makefile b/arch/riscv/kernel/tests/kprobes/Makefile
index 4cb6c66a98e8..df7256f62313 100644
--- a/arch/riscv/kernel/tests/kprobes/Makefile
+++ b/arch/riscv/kernel/tests/kprobes/Makefile
@@ -1 +1,3 @@
-obj-y += test-kprobes.o test-kprobes-asm.o
+obj-$(CONFIG_RISCV_KPROBES_KUNIT) += kprobes_riscv_kunit.o
+
+kprobes_riscv_kunit-objs := test-kprobes.o test-kprobes-asm.o
diff --git a/arch/riscv/kernel/tests/kprobes/test-kprobes.c b/arch/riscv/kernel/tests/kprobes/test-kprobes.c
index 6f6cdfbf5a95..664535ca0a98 100644
--- a/arch/riscv/kernel/tests/kprobes/test-kprobes.c
+++ b/arch/riscv/kernel/tests/kprobes/test-kprobes.c
@@ -49,8 +49,11 @@ static struct kunit_case kprobes_testcases[] = {
 };
 
 static struct kunit_suite kprobes_test_suite = {
-	.name = "kprobes_test_riscv",
+	.name = "kprobes_riscv",
 	.test_cases = kprobes_testcases,
 };
 
 kunit_test_suites(&kprobes_test_suite);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("KUnit test for riscv kprobes");