diff --git a/ipc/shm.c b/ipc/shm.c
index 32b65f7..9c687cd 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1127,9 +1127,17 @@
 		goto out;
 	else if ((addr = (ulong)shmaddr)) {
 		if (addr & (shmlba - 1)) {
-			if (shmflg & SHM_RND)
+			if (shmflg & SHM_RND) {
 				addr &= ~(shmlba - 1);  /* round down */
-			else
+
+				/*
+				 * Ensure that the round-down is non-nil
+				 * when remapping. This can happen for
+				 * cases when addr < shmlba.
+				 */
+				if (!addr && (shmflg & SHM_REMAP))
+					goto out;
+			} else
 #ifndef __ARCH_FORCE_SHMLBA
 				if (addr & ~PAGE_MASK)
 #endif