From: Kees Cook Date: Thu, 30 Nov 2023 20:56:08 +0000 (-0800) Subject: tracing/uprobe: Replace strlcpy() with strscpy() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=8a3750ecf8104de55c569ffbe844a85aa9d5deaa;p=linux.git tracing/uprobe: Replace 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]. Additionally, it returns the size of the source string, not the resulting size of the destination string. In an effort to remove strlcpy() completely[2], replace strlcpy() here with strscpy(). The negative return value is already handled by this code so no new handling is needed here. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [1] Link: https://github.com/KSPP/linux/issues/89 [2] Cc: Steven Rostedt Cc: Masami Hiramatsu Cc: linux-trace-kernel@vger.kernel.org Acked-by: "Masami Hiramatsu (Google)" Link: https://lore.kernel.org/r/20231130205607.work.463-kees@kernel.org Signed-off-by: Kees Cook --- diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 99c051de412af..a84b85d8aac12 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -151,7 +151,7 @@ fetch_store_string(unsigned long addr, void *dest, void *base) return -ENOMEM; if (addr == FETCH_TOKEN_COMM) - ret = strlcpy(dst, current->comm, maxlen); + ret = strscpy(dst, current->comm, maxlen); else ret = strncpy_from_user(dst, src, maxlen); if (ret >= 0) {