diff --git a/libc/include/bits/fortify/socket.h b/libc/include/bits/fortify/socket.h
index 9e7df6d..8297580 100644
--- a/libc/include/bits/fortify/socket.h
+++ b/libc/include/bits/fortify/socket.h
@@ -30,15 +30,15 @@
 #error "Never include this file directly; instead, include <sys/socket.h>"
 #endif
 
-extern ssize_t __sendto_chk(int, const void*, size_t, size_t, int, const struct sockaddr*,
+extern ssize_t __sendto_chk(int, const void* _Nonnull, size_t, size_t, int, const struct sockaddr* _Nullable,
         socklen_t) __INTRODUCED_IN(26);
-ssize_t __recvfrom_chk(int, void*, size_t, size_t, int, struct sockaddr*,
-        socklen_t*) __INTRODUCED_IN(21);
+ssize_t __recvfrom_chk(int, void* _Nullable, size_t, size_t, int, struct sockaddr* _Nullable,
+        socklen_t* _Nullable) __INTRODUCED_IN(21);
 
 #if defined(__BIONIC_FORTIFY)
 
 __BIONIC_FORTIFY_INLINE
-ssize_t recvfrom(int fd, void* const buf __pass_object_size0, size_t len, int flags, struct sockaddr* src_addr, socklen_t* addr_len)
+ssize_t recvfrom(int fd, void* _Nullable const buf __pass_object_size0, size_t len, int flags, struct sockaddr* _Nullable src_addr, socklen_t* _Nullable addr_len)
     __overloadable
     __clang_error_if(__bos_unevaluated_lt(__bos0(buf), len),
                      "'recvfrom' called with size bigger than buffer") {
@@ -53,7 +53,7 @@
 }
 
 __BIONIC_FORTIFY_INLINE
-ssize_t sendto(int fd, const void* const buf __pass_object_size0, size_t len, int flags, const struct sockaddr* dest_addr, socklen_t addr_len)
+ssize_t sendto(int fd, const void* _Nonnull const buf __pass_object_size0, size_t len, int flags, const struct sockaddr* _Nullable dest_addr, socklen_t addr_len)
     __overloadable
     __clang_error_if(__bos_unevaluated_lt(__bos0(buf), len),
                      "'sendto' called with size bigger than buffer") {
@@ -68,7 +68,7 @@
 }
 
 __BIONIC_FORTIFY_INLINE
-ssize_t recv(int socket, void* const buf __pass_object_size0, size_t len, int flags)
+ssize_t recv(int socket, void* _Nullable const buf __pass_object_size0, size_t len, int flags)
     __overloadable
     __clang_error_if(__bos_unevaluated_lt(__bos0(buf), len),
                      "'recv' called with size bigger than buffer") {
@@ -76,7 +76,7 @@
 }
 
 __BIONIC_FORTIFY_INLINE
-ssize_t send(int socket, const void* const buf __pass_object_size0, size_t len, int flags)
+ssize_t send(int socket, const void* _Nonnull const buf __pass_object_size0, size_t len, int flags)
     __overloadable
     __clang_error_if(__bos_unevaluated_lt(__bos0(buf), len),
                      "'send' called with size bigger than buffer") {