[PATCH] kernel: debug: Replace deprecated strcpy() with strscpy()

[PATCH] kernel: debug: Replace deprecated strcpy() with strscpy()

[Thorsten Blum]

strcpy() is deprecated; use strscpy() instead.

Link: https://github.com/KSPP/linux/issues/88
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 kernel/debug/gdbstub.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index f625172d4b67..22fe969c5d2e 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -30,6 +30,7 @@
 #include <linux/kgdb.h>
 #include <linux/kdb.h>
 #include <linux/serial_core.h>
+#include <linux/string.h>
 #include <linux/reboot.h>
 #include <linux/uaccess.h>
 #include <asm/cacheflush.h>
@@ -547,7 +548,7 @@ static void gdb_cmd_setregs(struct kgdb_state *ks)
 		error_packet(remcom_out_buffer, -EINVAL);
 	} else {
 		gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs);
-		strcpy(remcom_out_buffer, "OK");
+		strscpy(remcom_out_buffer, "OK");
 	}
 }
 
@@ -577,7 +578,7 @@ static void gdb_cmd_memwrite(struct kgdb_state *ks)
 	if (err)
 		error_packet(remcom_out_buffer, err);
 	else
-		strcpy(remcom_out_buffer, "OK");
+		strscpy(remcom_out_buffer, "OK");
 }
 
 #if DBG_MAX_REG_NUM > 0
@@ -630,7 +631,7 @@ static void gdb_cmd_reg_set(struct kgdb_state *ks)
 	i = i / 2;
 	kgdb_hex2mem(ptr, (char *)gdb_regs, i);
 	dbg_set_reg(regnum, gdb_regs, ks->linux_regs);
-	strcpy(remcom_out_buffer, "OK");
+	strscpy(remcom_out_buffer, "OK");
 }
 #endif /* DBG_MAX_REG_NUM > 0 */
 
@@ -642,7 +643,7 @@ static void gdb_cmd_binwrite(struct kgdb_state *ks)
 	if (err)
 		error_packet(remcom_out_buffer, err);
 	else
-		strcpy(remcom_out_buffer, "OK");
+		strscpy(remcom_out_buffer, "OK");
 }
 
 /* Handle the 'D' or 'k', detach or kill packets */
@@ -656,7 +657,7 @@ static void gdb_cmd_detachkill(struct kgdb_state *ks)
 		if (error < 0) {
 			error_packet(remcom_out_buffer, error);
 		} else {
-			strcpy(remcom_out_buffer, "OK");
+			strscpy(remcom_out_buffer, "OK");
 			kgdb_connected = 0;
 		}
 		put_packet(remcom_out_buffer);
@@ -676,7 +677,7 @@ static int gdb_cmd_reboot(struct kgdb_state *ks)
 	/* For now, only honor R0 */
 	if (strcmp(remcom_in_buffer, "R0") == 0) {
 		printk(KERN_CRIT "Executing emergency reboot\n");
-		strcpy(remcom_out_buffer, "OK");
+		strscpy(remcom_out_buffer, "OK");
 		put_packet(remcom_out_buffer);
 
 		/*
@@ -739,7 +740,7 @@ static void gdb_cmd_query(struct kgdb_state *ks)
 
 	case 'C':
 		/* Current thread id */
-		strcpy(remcom_out_buffer, "QC");
+		strscpy(remcom_out_buffer, "QC");
 		ks->threadid = shadow_pid(current->pid);
 		int_to_threadref(thref, ks->threadid);
 		pack_threadid(remcom_out_buffer + 2, thref);
@@ -773,7 +774,7 @@ static void gdb_cmd_query(struct kgdb_state *ks)
 			int len = strlen(remcom_in_buffer + 6);
 
 			if ((len % 2) != 0) {
-				strcpy(remcom_out_buffer, "E01");
+				strscpy(remcom_out_buffer, "E01");
 				break;
 			}
 			kgdb_hex2mem(remcom_in_buffer + 6,
@@ -785,14 +786,14 @@ static void gdb_cmd_query(struct kgdb_state *ks)
 			kdb_parse(remcom_out_buffer);
 			kdb_common_deinit_state();
 
-			strcpy(remcom_out_buffer, "OK");
+			strscpy(remcom_out_buffer, "OK");
 		}
 		break;
 #endif
 #ifdef CONFIG_HAVE_ARCH_KGDB_QXFER_PKT
 	case 'S':
 		if (!strncmp(remcom_in_buffer, "qSupported:", 11))
-			strcpy(remcom_out_buffer, kgdb_arch_gdb_stub_feature);
+			strscpy(remcom_out_buffer, kgdb_arch_gdb_stub_feature);
 		break;
 	case 'X':
 		if (!strncmp(remcom_in_buffer, "qXfer:", 6))
@@ -822,7 +823,7 @@ static void gdb_cmd_task(struct kgdb_state *ks)
 		}
 		kgdb_usethread = thread;
 		ks->kgdb_usethreadid = ks->threadid;
-		strcpy(remcom_out_buffer, "OK");
+		strscpy(remcom_out_buffer, "OK");
 		break;
 	case 'c':
 		ptr = &remcom_in_buffer[2];
@@ -837,7 +838,7 @@ static void gdb_cmd_task(struct kgdb_state *ks)
 			}
 			kgdb_contthread = thread;
 		}
-		strcpy(remcom_out_buffer, "OK");
+		strscpy(remcom_out_buffer, "OK");
 		break;
 	}
 }
@@ -851,7 +852,7 @@ static void gdb_cmd_thread(struct kgdb_state *ks)
 	kgdb_hex2long(&ptr, &ks->threadid);
 	thread = getthread(ks->linux_regs, ks->threadid);
 	if (thread)
-		strcpy(remcom_out_buffer, "OK");
+		strscpy(remcom_out_buffer, "OK");
 	else
 		error_packet(remcom_out_buffer, -EINVAL);
 }
@@ -913,7 +914,7 @@ static void gdb_cmd_break(struct kgdb_state *ks)
 			(int) length, *bpt_type - '0');
 
 	if (error == 0)
-		strcpy(remcom_out_buffer, "OK");
+		strscpy(remcom_out_buffer, "OK");
 	else
 		error_packet(remcom_out_buffer, error);
 }
-- 
2.50.1

Re: [PATCH] kernel: debug: Replace deprecated strcpy() with strscpy()

[Doug Anderson]

Hi,

On Fri, Jul 18, 2025 at 12:32 PM Thorsten Blum <thorsten.blum@linux.dev> wrote:
>
> strcpy() is deprecated; use strscpy() instead.
>
> Link: https://github.com/KSPP/linux/issues/88
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
> ---
>  kernel/debug/gdbstub.c | 29 +++++++++++++++--------------
>  1 file changed, 15 insertions(+), 14 deletions(-)

nit: Since this only covers things in the file `gdbstub.c` and not
everything in kernel/debug, perhaps that should be in the subject
line? Maybe "kernel: debug: gdbstub: Replace deprecated strcpy() with
strscpy()"?

Other than that, this looks fine to me.

Reviewed-by: Douglas Anderson <dianders@chromium.org>