diff --git a/Kernel/API/POSIX/sys/mman.h b/Kernel/API/POSIX/sys/mman.h
index 3c996e9699..65a6618385 100644
--- a/Kernel/API/POSIX/sys/mman.h
+++ b/Kernel/API/POSIX/sys/mman.h
@@ -34,6 +34,10 @@ extern "C" {
 #define MADV_SET_VOLATILE 0x100
 #define MADV_SET_NONVOLATILE 0x200
 
+#define MS_SYNC 1
+#define MS_ASYNC 2
+#define MS_INVALIDATE 4
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/Kernel/API/Syscall.h b/Kernel/API/Syscall.h
index c321b4b7f9..40e55642b1 100644
--- a/Kernel/API/Syscall.h
+++ b/Kernel/API/Syscall.h
@@ -124,6 +124,7 @@ enum class NeedsBigProcessLock {
     S(mount, NeedsBigProcessLock::Yes)                      \
     S(mprotect, NeedsBigProcessLock::Yes)                   \
     S(mremap, NeedsBigProcessLock::Yes)                     \
+    S(msync, NeedsBigProcessLock::Yes)                      \
     S(msyscall, NeedsBigProcessLock::Yes)                   \
     S(munmap, NeedsBigProcessLock::Yes)                     \
     S(open, NeedsBigProcessLock::Yes)                       \
diff --git a/Kernel/Memory/SharedInodeVMObject.cpp b/Kernel/Memory/SharedInodeVMObject.cpp
index 605af54e18..15ad1c39e2 100644
--- a/Kernel/Memory/SharedInodeVMObject.cpp
+++ b/Kernel/Memory/SharedInodeVMObject.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <Kernel/FileSystem/Inode.h>
+#include <Kernel/Locking/Spinlock.h>
 #include <Kernel/Memory/SharedInodeVMObject.h>
 
 namespace Kernel::Memory {
@@ -34,4 +35,22 @@ SharedInodeVMObject::SharedInodeVMObject(SharedInodeVMObject const& other)
 {
 }
 
+ErrorOr<void> SharedInodeVMObject::sync()
+{
+    SpinlockLocker locker(m_lock);
+
+    for (size_t page_index = 0; page_index < page_count(); ++page_index) {
+        auto& physical_page = m_physical_pages[page_index];
+        if (!physical_page)
+            continue;
+
+        u8 page_buffer[PAGE_SIZE];
+        MM.copy_physical_page(*physical_page, page_buffer);
+
+        TRY(m_inode->write_bytes(page_index * PAGE_SIZE, PAGE_SIZE, UserOrKernelBuffer::for_kernel_buffer(page_buffer), nullptr));
+    }
+
+    return {};
+}
+
 }
diff --git a/Kernel/Memory/SharedInodeVMObject.h b/Kernel/Memory/SharedInodeVMObject.h
index c596addbf9..81d6a93ca0 100644
--- a/Kernel/Memory/SharedInodeVMObject.h
+++ b/Kernel/Memory/SharedInodeVMObject.h
@@ -18,6 +18,8 @@ public:
     static ErrorOr<NonnullRefPtr<SharedInodeVMObject>> try_create_with_inode(Inode&);
     virtual ErrorOr<NonnullRefPtr<VMObject>> try_clone() override;
 
+    ErrorOr<void> sync();
+
 private:
     virtual bool is_shared_inode() const override { return true; }
 
diff --git a/Kernel/Process.h b/Kernel/Process.h
index 3fe8fe2f55..bc9ff41679 100644
--- a/Kernel/Process.h
+++ b/Kernel/Process.h
@@ -313,6 +313,7 @@ public:
     ErrorOr<FlatPtr> sys$mprotect(Userspace<void*>, size_t, int prot);
     ErrorOr<FlatPtr> sys$madvise(Userspace<void*>, size_t, int advice);
     ErrorOr<FlatPtr> sys$msyscall(Userspace<void*>);
+    ErrorOr<FlatPtr> sys$msync(Userspace<void*>, size_t, int flags);
     ErrorOr<FlatPtr> sys$purge(int mode);
     ErrorOr<FlatPtr> sys$select(Userspace<const Syscall::SC_select_params*>);
     ErrorOr<FlatPtr> sys$poll(Userspace<const Syscall::SC_poll_params*>);
diff --git a/Kernel/Syscalls/mmap.cpp b/Kernel/Syscalls/mmap.cpp
index 68a001890d..1b3e99b755 100644
--- a/Kernel/Syscalls/mmap.cpp
+++ b/Kernel/Syscalls/mmap.cpp
@@ -589,4 +589,21 @@ ErrorOr<FlatPtr> Process::sys$msyscall(Userspace<void*> address)
     region->set_syscall_region(true);
     return 0;
 }
+
+ErrorOr<FlatPtr> Process::sys$msync(Userspace<void*> address, size_t size, [[maybe_unused]] int flags)
+{
+    // FIXME: We probably want to sync all mappings in the address+size range.
+    auto* region = address_space().find_region_from_range(Memory::VirtualRange { address.vaddr(), size });
+    if (!region)
+        return EINVAL;
+
+    auto& vmobject = region->vmobject();
+    if (!vmobject.is_shared_inode())
+        return 0;
+
+    auto& inode_vmobject = static_cast<Memory::SharedInodeVMObject&>(vmobject);
+    TRY(inode_vmobject.sync());
+    return 0;
+}
+
 }
diff --git a/Userland/Libraries/LibC/sys/mman.cpp b/Userland/Libraries/LibC/sys/mman.cpp
index 457ddd4393..fa2479f4f6 100644
--- a/Userland/Libraries/LibC/sys/mman.cpp
+++ b/Userland/Libraries/LibC/sys/mman.cpp
@@ -89,4 +89,10 @@ int mlock(const void*, size_t)
     dbgln("FIXME: Implement mlock()");
     return 0;
 }
+
+int msync(void* address, size_t size, int flags)
+{
+    int rc = syscall(SC_msync, address, size, flags);
+    __RETURN_WITH_ERRNO(rc, rc, -1);
+}
 }
diff --git a/Userland/Libraries/LibC/sys/mman.h b/Userland/Libraries/LibC/sys/mman.h
index 2f694ff541..c1eacbe127 100644
--- a/Userland/Libraries/LibC/sys/mman.h
+++ b/Userland/Libraries/LibC/sys/mman.h
@@ -20,5 +20,6 @@ int set_mmap_name(void*, size_t, const char*);
 int madvise(void*, size_t, int advice);
 void* allocate_tls(const char* initial_data, size_t);
 int mlock(const void*, size_t);
+int msync(void*, size_t, int flags);
 
 __END_DECLS