diff options
| -rw-r--r-- | exec/exec.c | 69 |
1 files changed, 47 insertions, 22 deletions
diff --git a/exec/exec.c b/exec/exec.c index 4fd3135e..cd960011 100644 --- a/exec/exec.c +++ b/exec/exec.c @@ -18,7 +18,7 @@ it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. -The GNU Hurd is distributed in the hope that it will be useful, +The GNU Hurd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. @@ -237,7 +237,7 @@ load_section (void *section, struct execdata *u) u->error = vm_map (u->task, &mapstart, filesz - (mapstart - addr), mask, anywhere, - u->filemap, filepos + (mapstart - addr), 1, + u->filemap, filepos + (mapstart - addr), 1, vm_prot, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE, VM_INHERIT_COPY); @@ -392,9 +392,34 @@ load_section (void *section, struct execdata *u) vm_deallocate (u->task, mapstart, memsz); return; } - bzero ((void *) (ourpage + (addr - overlap_page)), - size - (addr - overlap_page)); - if (!(vm_prot & VM_PROT_WRITE)) + { + /* Zero the appropriate portion of our copy of the page. All + this rigamorole is in case the memory backing this page is + bogus and we fault in bzero; we want to return the fault's + error code to the user, rather than crash the server. */ + jmp_buf env; + void fault (int signo) { longjmp (env, 1); } + thread_t thisthread = hurd_thread_self (); + sighandler_t preempt (thread_t thread, int signo, + long int sigcode, int sigerror) + { + if (thread == thisthread) + { + u->error = sigerror ?: EIO; + return &fault; + } + return SIG_DFL; + } + struct hurd_signal_preempt preempter; + hurd_preempt_signals (&preempter, SIGSEGV, + ourpage, ourpage + vm_page_size, + &preempt); + if (! setjmp (env)) + bzero ((void *) (ourpage + (addr - overlap_page)), + size - (addr - overlap_page)); + hurd_unpreempt_signals (&preempter, SIGSEGV); + } + if (! u->error && !(vm_prot & VM_PROT_WRITE)) u->error = vm_protect (u->task, overlap_page, size, 0, VM_PROT_WRITE); if (! u->error) @@ -565,7 +590,7 @@ prepare (file_t file, struct execdata *e) else e->error = vm_map (mach_task_self (), (vm_address_t *) &e->cntl, vm_page_size, 0, 1, e->cntlmap, 0, 0, - VM_PROT_READ|VM_PROT_WRITE, + VM_PROT_READ|VM_PROT_WRITE, VM_PROT_READ|VM_PROT_WRITE, VM_INHERIT_NONE); if (e->cntl) @@ -738,7 +763,7 @@ check_elf_phdr (struct execdata *e, const Elf32_Phdr *mapped_phdr, phdr->p_filesz)) e->error = EINVAL; break; - } + } } @@ -787,7 +812,7 @@ finish_mapping (struct execdata *e) e->cntlmap = MACH_PORT_NULL; } } - + /* Clean up after reading the file (need not be completed). */ void finish (struct execdata *e, int dealloc_file) @@ -869,12 +894,12 @@ load (task_t usertask, struct execdata *e) vm_address_t myaddr, a; vm_size_t mysize; myaddr = 0; - + /* We have already mapped the file into the task in load_section. Now read from the task's memory into our own address space so we can peek each page and cause it to be paged in. */ - u->error = vm_read (u->task, trunc_page (addr), + u->error = vm_read (u->task, trunc_page (addr), round_page (secsize), &myaddr, &mysize); if (u->error) return; @@ -1041,7 +1066,7 @@ do_exec (file_t file, vm_address_t phdr_addr = 0; vm_size_t phdr_size = 0; mach_msg_type_number_t i; - + /* Prime E for executing FILE and check its validity. This must be an inline function because it stores pointers into alloca'd storage in E for later use in `load'. */ @@ -1136,7 +1161,7 @@ do_exec (file_t file, if (flags & (EXEC_NEWTASK|EXEC_SECURE)) { /* Create the new task. If we are not being secure, then use OLDTASK - for the task_create RPC, in case it is something magical. */ + for the task_create RPC, in case it is something magical. */ e.error = task_create (((flags & EXEC_SECURE) || oldtask == MACH_PORT_NULL) ? mach_task_self () : oldtask, @@ -1169,7 +1194,7 @@ do_exec (file_t file, e.error = io_reauthenticate (new, ref, MACH_MSG_TYPE_MAKE_SEND); if (! e.error) e.error = auth_user_authenticate - (boot->portarray[INIT_PORT_AUTH], + (boot->portarray[INIT_PORT_AUTH], new, ref, MACH_MSG_TYPE_MAKE_SEND, &authed); mach_port_destroy (mach_task_self (), ref); if (e.error) @@ -1182,7 +1207,7 @@ do_exec (file_t file, mach_port_mod_refs (mach_task_self (), new, MACH_PORT_RIGHT_SEND, 1); } - + boot->portarray[idx] = new; ports_replaced[idx] = 1; } @@ -1288,11 +1313,11 @@ do_exec (file_t file, if ((secure || defaults) && boot->portarray[INIT_PORT_AUTH] == MACH_PORT_NULL) /* Q: Doesn't this let anyone run a program and make it - get a root auth port? + get a root auth port? A: No; the standard port for INIT_PORT_AUTH has no UID's at all. See init.trim/init.c (init_stdarrays). */ use (INIT_PORT_AUTH, std_ports[INIT_PORT_AUTH], 0, 0); - if (secure || (defaults + if (secure || (defaults && boot->portarray[INIT_PORT_PROC] == MACH_PORT_NULL)) { /* Ask the proc server for the proc port for this task. */ @@ -1305,13 +1330,13 @@ do_exec (file_t file, /* XXX We should also call proc_setowner at this point. */ } - else if (oldtask != newtask && oldtask != MACH_PORT_NULL + else if (oldtask != newtask && oldtask != MACH_PORT_NULL && boot->portarray[INIT_PORT_PROC] != MACH_PORT_NULL) { mach_port_t new; /* This task port refers to the old task; use it to fetch a new one for the new task. */ - e.error = proc_task2proc (boot->portarray[INIT_PORT_PROC], + e.error = proc_task2proc (boot->portarray[INIT_PORT_PROC], newtask, &new); if (e.error) goto stdout; @@ -1323,7 +1348,7 @@ do_exec (file_t file, if ((secure || defaults) && boot->portarray[INIT_PORT_CWDIR] == MACH_PORT_NULL) use (INIT_PORT_CWDIR, std_ports[INIT_PORT_CWDIR], 1, 0); - } + } rwlock_reader_unlock (&std_lock); @@ -1457,7 +1482,7 @@ do_exec (file_t file, for (i = 0; i < ndestroynames; ++i) mach_port_destroy (oldtask, destroynames[i]); } - + /* XXX this should be below it is here to work around a vm_map kernel bug. */ if (interp.file != MACH_PORT_NULL) @@ -1490,7 +1515,7 @@ do_exec (file_t file, /* Start up the initial thread at the entry point. */ boot->stack_base = 0, boot->stack_size = 0; /* Don't care about values. */ - e.error = mach_setup_thread (newtask, thread, + e.error = mach_setup_thread (newtask, thread, (void *) (e.interp.section ? interp.entry : e.entry), &boot->stack_base, &boot->stack_size); @@ -1740,7 +1765,7 @@ S_exec_setexecdata (struct trivfs_protid *protid, mach_msg_type_number_t i; for (i = 0; i < std_nports; ++i) mach_port_deallocate (mach_task_self (), std_ports[i]); - vm_deallocate (mach_task_self (), (vm_address_t)std_ports, + vm_deallocate (mach_task_self (), (vm_address_t)std_ports, std_nports * sizeof (mach_port_t)); } |