base: enable executable memory fault handling

Fixes #1723

repos/base-fiasco/src/core/include/ipc_pager.h

@@ -48,11 +48,10 @@ namespace Genode {
 			 */
 			Mapping(addr_t dst_addr, addr_t src_addr,
 			        Cache_attribute cacheability, bool io_mem,
-			        unsigned l2size = L4_LOG2_PAGESIZE,
+			        unsigned l2size, bool rw, bool executable)
-			        bool rw = true, bool grant = false)
 			:
 				_dst_addr(dst_addr),
-				_fpage(Fiasco::l4_fpage(src_addr, l2size, rw, grant))
+				_fpage(Fiasco::l4_fpage(src_addr, l2size, rw, false))
 			{
 				if (cacheability == WRITE_COMBINED)
 					_fpage.fp.cache = Fiasco::L4_FPAGE_BUFFERABLE;
@@ -163,6 +162,8 @@ namespace Genode {
 
 			bool write_fault() const { return (_pf_addr & 2); }
 
+			bool exec_fault()  const { return false; }
+
 			/**
 			 * Return true if last fault was an exception
 			 */

repos/base-foc/src/core/include/ipc_pager.h

@@ -45,7 +45,6 @@ namespace Genode {
 			bool            _iomem;
 			unsigned        _log2size;
 			bool            _rw;
-			bool            _grant;
 
 		public:
 
@@ -54,20 +53,20 @@ namespace Genode {
 			 */
 			Mapping(addr_t dst_addr, addr_t src_addr,
 			        Cache_attribute c, bool io_mem,
-			        unsigned l2size = L4_LOG2_PAGESIZE,
+			        unsigned l2size,
-			        bool rw = true, bool grant = false)
+			        bool rw, bool executable)
 			: _dst_addr(dst_addr), _src_addr(src_addr),
 				_cacheability(c), _iomem(io_mem), _log2size(l2size),
-			  _rw(rw), _grant(grant) { }
+			  _rw(rw) { }
 
 			/**
 			 * Construct invalid flexpage
 			 */
 			Mapping() : _dst_addr(0), _src_addr(0), _cacheability(UNCACHED),
-				_iomem(false), _log2size(0), _rw(false), _grant(false) { }
+				_iomem(false), _log2size(0), _rw(false) { }
 
 			Fiasco::l4_umword_t dst_addr() const { return _dst_addr; }
-			bool                grant()    const { return _grant;    }
+			bool                grant()    const { return false; }
 
 			Fiasco::l4_fpage_t  fpage()    const
 			{
@@ -176,6 +175,8 @@ namespace Genode {
 
 			bool write_fault() const { return (_pf_addr & 2); }
 
+			bool exec_fault()  const { return false; }
+
 			/**
 			 * Return true if last fault was an exception
 			 */

repos/base-hw/src/core/pager.h

@@ -65,7 +65,8 @@ struct Genode::Mapping : Hw::Mapping
 	        Cache_attribute cacheable,
 	        bool io,
 	        unsigned size_log2,
-	        bool writeable)
+	        bool writeable,
+	        bool executable)
 	: Hw::Mapping(phys, virt, 1 << size_log2,
 	              { writeable ? Hw::RW : Hw::RO, Hw::EXEC, Hw::USER,
 	                Hw::NO_GLOBAL, io ? Hw::DEVICE : Hw::RAM, cacheable }) {}
@@ -108,6 +109,11 @@ class Genode::Ipc_pager
 		 */
 		bool write_fault() const;
 
+		/**
+		 * Executable permission fault
+		 */
+		bool exec_fault() const { return false; }
+
 		/**
 		 * Input mapping data as reply to current page fault
 		 */

repos/base-nova/src/core/include/ipc_pager.h

@@ -43,8 +43,8 @@ namespace Genode {
 			 */
 			Mapping(addr_t dst_addr, addr_t map_addr,
 			        Cache_attribute c, bool io_mem,
-			        unsigned size_log2 = PAGE_SIZE_LOG2,
+			        unsigned size_log2,
-			        bool rw = true)
+			        bool rw, bool executable)
 			:
 				_dst_addr(dst_addr), _core_local_addr(map_addr),
 				_attr(c), _size_log2(size_log2), _rw(rw)
@@ -125,6 +125,11 @@ namespace Genode {
 			 */
 			bool write_fault() const { return _fault_type & ERR_W; }
 
+			/**
+			 * Return true if fault was a non-executable fault
+			 */
+			bool exec_fault() const { return false; }
+
 			/**
 			 * Return true if last fault was an exception
 			 */

repos/base-okl4/src/core/include/ipc_pager.h

@@ -41,7 +41,7 @@ namespace Genode {
 			 */
 			Mapping(addr_t dst_addr, addr_t src_addr,
 			        Cache_attribute cacheability, bool io_mem,
-			        unsigned l2size = 12, bool rw = true);
+			        unsigned l2size, bool rw, bool executable);
 
 			/**
 			 * Construct invalid mapping
@@ -162,6 +162,11 @@ namespace Genode {
 			 */
 			bool write_fault() const { return L4_Label(_faulter_tag) & 2; }
 
+			/**
+			 * Return true if last fault was a executable fault
+			 */
+			bool exec_fault() const { return false; }
+
 			/**
 			 * Return true if last fault was an exception
 			 */

repos/base-okl4/src/core/pager.cc

@@ -73,7 +73,7 @@ static inline Okl4::L4_ThreadId_t thread_get_my_global_id()
 
 Mapping::Mapping(addr_t dst_addr, addr_t src_addr,
                  Cache_attribute cacheability, bool io_mem,
-                 unsigned l2size, bool rw)
+                 unsigned l2size, bool rw, bool executable)
 :
 	_fpage(L4_FpageLog2(dst_addr, l2size)),
 	/*

repos/base-pistachio/src/core/include/ipc_pager.h

@@ -46,8 +46,8 @@ namespace Genode {
 			 */
 			Mapping(addr_t dst_addr, addr_t src_addr,
 			        Cache_attribute, bool io_mem,
-			        unsigned l2size = Pistachio::get_page_size_log2(),
+			        unsigned l2size,
-			        bool rw = true, bool grant = false);
+			        bool rw, bool executable);
 
 			/**
 			 * Construct invalid mapping
@@ -169,6 +169,11 @@ namespace Genode {
 			 */
 			bool write_fault() const { return (_flags & 2); }
 
+			/**
+			 * Return true if last fault was a executable fault
+			 */
+			bool exec_fault() const { return false; }
+
 			/**
 			 * Return true if last fault was an exception
 			 */

repos/base-pistachio/src/core/pager.cc

@@ -41,8 +41,10 @@ using namespace Pistachio;
 
 Mapping::Mapping(addr_t dst_addr, addr_t src_addr,
                  Cache_attribute, bool io_mem, unsigned l2size,
-                 bool rw, bool grant)
+                 bool rw, bool executable)
 {
+	bool const grant = false;
+
 	L4_Fpage_t fpage = L4_FpageLog2(src_addr, l2size);
 
 	fpage += rw ? L4_FullyAccessible : L4_Readable;

repos/base-sel4/src/core/include/ipc_pager.h

@@ -44,8 +44,7 @@ namespace Genode {
 			 */
 			Mapping(addr_t dst_addr, addr_t src_addr,
 			        Cache_attribute const cacheability, bool io_mem,
-			        unsigned l2size = PAGE_SIZE_LOG2,
+			        unsigned l2size, bool rw, bool executable)
-			        bool rw = true)
 			:
 				_from_phys_addr(src_addr),
 				_to_virt_addr(dst_addr),
@@ -142,6 +141,11 @@ namespace Genode {
 			 * Return true if page fault was a write fault
 			 */
 			bool write_fault() const { return _pf_write; }
+
+			/**
+			 * Return true if page fault was on non-executable memory
+			 */
+			bool exec_fault() const { return false; }
 	};
 }
 

repos/base/src/core/include/region_map_component.h

@@ -65,6 +65,7 @@ class Genode::Rm_region : public List<Rm_region>::Element
 		addr_t                _base  = 0;
 		size_t                _size  = 0;
 		bool                  _write = false;
+		bool                  _exec  = false;
 
 		Dataspace_component  *_dsc   = nullptr;
 		off_t                 _off   = 0;
@@ -80,8 +81,8 @@ class Genode::Rm_region : public List<Rm_region>::Element
 
 		Rm_region(addr_t base, size_t size, bool write,
 		          Dataspace_component *dsc, off_t offset,
-		          Region_map_component *rm)
+		          Region_map_component *rm, bool exec)
-		: _base(base), _size(size), _write(write),
+		: _base(base), _size(size), _write(write), _exec(exec),
 		  _dsc(dsc), _off(offset), _rm(rm) { }
 
 
@@ -92,6 +93,7 @@ class Genode::Rm_region : public List<Rm_region>::Element
 		addr_t                     base() const { return _base;  }
 		size_t                     size() const { return _size;  }
 		bool                      write() const { return _write; }
+		bool                 executable() const { return _exec;  }
 		Dataspace_component*  dataspace() const { return _dsc;   }
 		off_t                    offset() const { return _off;   }
 		Region_map_component*        rm() const { return _rm;    }

repos/base/src/core/region_map_component.cc

@@ -156,8 +156,9 @@ static void print_page_fault(char const *msg,
                              Pager_object const &obj)
 {
 	log(msg, " (",
-	    pf_type == Region_map::State::WRITE_FAULT ? "WRITE" : "READ",
+	    pf_type == Region_map::State::WRITE_FAULT ? "WRITE" :
-	    " pf_addr=", Hex(pf_addr), " pf_ip=", Hex(pf_ip), " from ", obj, ")");
+	    pf_type == Region_map::State::READ_FAULT ? "READ" : "EXEC",
+	    " pf_addr=", Hex(pf_addr), " pf_ip=", Hex(pf_ip), " from ", obj, ") ");
 }
 
 
@@ -173,6 +174,9 @@ int Rm_client::pager(Ipc_pager &pager)
 {
 	Region_map::State::Fault_type pf_type = pager.write_fault() ? Region_map::State::WRITE_FAULT
 	                                                            : Region_map::State::READ_FAULT;
+	if (pager.exec_fault())
+		pf_type = Region_map::State::EXEC_FAULT;
+
 	addr_t pf_addr = pager.fault_addr();
 	addr_t pf_ip   = pager.fault_ip();
 
@@ -211,7 +215,6 @@ int Rm_client::pager(Ipc_pager &pager)
 		 */
 		if (pf_type == Region_map::State::WRITE_FAULT && !dsc->writable()) {
 
-			/* attempted there is no attachment return an error condition */
 			print_page_fault("attempted write at read-only memory",
 			                 pf_addr, pf_ip, pf_type, *this);
 
@@ -221,6 +224,17 @@ int Rm_client::pager(Ipc_pager &pager)
 			return 2;
 		}
 
+		if (pf_type == Region_map::State::EXEC_FAULT) {
+
+			print_page_fault("attempted exec at non-executable memory",
+			                 pf_addr, pf_ip, pf_type, *this);
+
+			/* register fault at responsible region map */
+			if (region_map)
+				region_map->fault(this, pf_addr - region_offset, pf_type);
+			return 3;
+		}
+
 		Mapping mapping = Region_map_component::create_map_item(region_map,
 		                                                        region,
 		                                                        ds_offset,
@@ -323,7 +337,7 @@ Mapping Region_map_component::create_map_item(Region_map_component *region_map,
 
 	return Mapping(dst_fault_area.base(), src_fault_area.base(),
 	               dsc->cacheability(), dsc->io_mem(),
-	               map_size_log2, dsc->writable());
+	               map_size_log2, dsc->writable(), region->executable());
 };
 
 
@@ -414,7 +428,7 @@ Region_map_component::attach(Dataspace_capability ds_cap, size_t size,
 		/* store attachment info in meta data */
 		try {
 			_map.metadata(attach_at, Rm_region((addr_t)attach_at, size, true,
-			                                   dsc, offset, this));
+			                                   dsc, offset, this, executable));
 
 		} catch (Allocator_avl_tpl<Rm_region>::Assign_metadata_failed) {