[PATCH v2] SUNRPC: Remove strlcpy

From: Azeem Shaikh
Date: Tue Jun 13 2023 - 20:12:57 EST


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 sysfs_emit().

Direct replacement is safe here since the getter in kernel_params_ops
handles -errno return [3].

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89
[3] https://elixir.bootlin.com/linux/v6.4-rc6/source/include/linux/moduleparam.h#L52

Signed-off-by: Azeem Shaikh <azeemshaikh38@xxxxxxxxx>
---
net/sunrpc/svc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index e6d4cec61e47..77326f163801 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -109,13 +109,13 @@ param_get_pool_mode(char *buf, const struct kernel_param *kp)
switch (*ip)
{
case SVC_POOL_AUTO:
- return strlcpy(buf, "auto\n", 20);
+ return sysfs_emit(buf, "auto\n");
case SVC_POOL_GLOBAL:
- return strlcpy(buf, "global\n", 20);
+ return sysfs_emit(buf, "global\n");
case SVC_POOL_PERCPU:
- return strlcpy(buf, "percpu\n", 20);
+ return sysfs_emit(buf, "percpu\n");
case SVC_POOL_PERNODE:
- return strlcpy(buf, "pernode\n", 20);
+ return sysfs_emit(buf, "pernode\n");
default:
return sprintf(buf, "%d\n", *ip);
}
--
2.41.0.162.gfafddb0af9-goog