[PATCH] nios2: Replace all non-returning strlcpy with strscpy

Azeem Shaikh
2023-05-30T16:24:37Z

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

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
---
arch/nios2/kernel/cpuinfo.c | 2 +-
arch/nios2/kernel/setup.c | 6 +++---
2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/nios2/kernel/cpuinfo.c b/arch/nios2/kernel/cpuinfo.c
index 203870c4b86d..338849c430a5 100644
--- 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 40bc8fb75e0b..8582ed965844 100644
--- 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