nios2: Replace all non-returning strlcpy with strscpy

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>

diff --git a/arch/nios2/kernel/cpuinfo.c b/arch/nios2/kernel/cpuinfo.c
index 203870c..338849c 100644 (file)
--- a/arch/nios2/kernel/cpuinfo.c
+++ b/arch/nios2/kernel/cpuinfo.c
@@ -47,7 +47,7 @@ void __init setup_cpuinfo(void)
 
        str = of_get_property(cpu, "altr,implementation", &len);
        if (str)
-               strlcpy(cpuinfo.cpu_impl, str, sizeof(cpuinfo.cpu_impl));
+               strscpy(cpuinfo.cpu_impl, str, sizeof(cpuinfo.cpu_impl));
        else
                strcpy(cpuinfo.cpu_impl, "<unknown>");
 

diff --git a/arch/nios2/kernel/setup.c b/arch/nios2/kernel/setup.c
index 40bc8fb..8582ed9 100644 (file)
--- a/arch/nios2/kernel/setup.c
+++ b/arch/nios2/kernel/setup.c
@@ -121,7 +121,7 @@ asmlinkage void __init nios2_boot_init(unsigned r4, unsigned r5, unsigned r6,
                dtb_passed = r6;
 
                if (r7)
-                       strlcpy(cmdline_passed, (char *)r7, COMMAND_LINE_SIZE);
+                       strscpy(cmdline_passed, (char *)r7, COMMAND_LINE_SIZE);
        }
 #endif
 
@@ -129,10 +129,10 @@ asmlinkage void __init nios2_boot_init(unsigned r4, unsigned r5, unsigned r6,
 
 #ifndef CONFIG_CMDLINE_FORCE
        if (cmdline_passed[0])
-               strlcpy(boot_command_line, cmdline_passed, COMMAND_LINE_SIZE);
+               strscpy(boot_command_line, cmdline_passed, COMMAND_LINE_SIZE);
 #ifdef CONFIG_NIOS2_CMDLINE_IGNORE_DTB
        else
-               strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
+               strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
 #endif
 #endif