net: Make copy_safe_from_sockptr() match documentation

Bastien Nocera · Bastien Nocera · commit 5fd497e2127d · 2025-04-14T09:44:08.000+02:00
JIRA: https://issues.redhat.com/browse/RHEL-74483 commit eb94b7b Author: Michal Luczaj <mhal@rbox.co> Date: Mon Nov 11 00:17:34 2024 +0100 net: Make copy_safe_from_sockptr() match documentation copy_safe_from_sockptr() return copy_from_sockptr() return copy_from_sockptr_offset() return copy_from_user() copy_from_user() does not return an error on fault. Instead, it returns a number of bytes that were not copied. Have it handled. Patch has a side effect: it un-breaks garbage input handling of nfc_llcp_setsockopt() and mISDN's data_sock_setsockopt(). Fixes: 6309863 ("net: add copy_safe_from_sockptr() helper") Signed-off-by: Michal Luczaj <mhal@rbox.co> Link: https://patch.msgid.link/20241111-sockptr-copy-ret-fix-v1-1-a520083a93fb@rbox.co Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Bastien Nocera <bnocera@redhat.com>
diff --git a/include/linux/sockptr.h b/include/linux/sockptr.h
@@ -77,7 +77,9 @@ static inline int copy_safe_from_sockptr(void *dst, size_t ksize,
 {
 	if (optlen < ksize)
 		return -EINVAL;
-	return copy_from_sockptr(dst, optval, ksize);
+	if (copy_from_sockptr(dst, optval, ksize))
+		return -EFAULT;
+	return 0;
 }
 
 static inline int copy_struct_from_sockptr(void *dst, size_t ksize,

Original file line number	Diff line number	Diff line change
`@@ -77,7 +77,9 @@ static inline int copy_safe_from_sockptr(void *dst, size_t ksize,`
`77`	`77`	`{`
`78`	`78`	`if (optlen < ksize)`
`79`	`79`	`return -EINVAL;`
`80`		`- return copy_from_sockptr(dst, optval, ksize);`
	`80`	`+ if (copy_from_sockptr(dst, optval, ksize))`
	`81`	`+ return -EFAULT;`
	`82`	`+ return 0;`
`81`	`83`	`}`
`82`	`84`
`83`	`85`	`static inline int copy_struct_from_sockptr(void *dst, size_t ksize,`