source: https://gitlab.com/qemu-project/qemu/-/issues/2353

diff --git a/linux-user/mmap.c b/linux-user/mmap.c
index be3b9a6..dad29ef 100644
--- a/linux-user/mmap.c
+++ b/linux-user/mmap.c
@@ -559,7 +559,7 @@ static abi_long mmap_h_eq_g(abi_ulong start, abi_ulong len,
                             int host_prot, int flags, int page_flags,
                             int fd, off_t offset)
 {
-    void *p, *want_p = g2h_untagged(start);
+    void *p, *want_p = start ? g2h_untagged(start) : 0;
     abi_ulong last;
 
     p = mmap(want_p, len, host_prot, flags, fd, offset);
@@ -609,7 +609,7 @@ static abi_long mmap_h_lt_g(abi_ulong start, abi_ulong len, int host_prot,
                             int mmap_flags, int page_flags, int fd,
                             off_t offset, int host_page_size)
 {
-    void *p, *want_p = g2h_untagged(start);
+    void *p, *want_p = start ? g2h_untagged(start) : 0;
     off_t fileend_adj = 0;
     int flags = mmap_flags;
     abi_ulong last, pass_last;
@@ -739,7 +739,7 @@ static abi_long mmap_h_gt_g(abi_ulong start, abi_ulong len,
                             int flags, int page_flags, int fd,
                             off_t offset, int host_page_size)
 {
-    void *p, *want_p = g2h_untagged(start);
+    void *p, *want_p = start ? g2h_untagged(start) : 0;
     off_t host_offset = offset & -host_page_size;
     abi_ulong last, real_start, real_last;
     bool misaligned_offset = false;