diff options
Diffstat (limited to 'sys/kern/kern_exec.c')
| -rw-r--r-- | sys/kern/kern_exec.c | 81 |
1 files changed, 62 insertions, 19 deletions
diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c index fd12717ce6a..7fb2276bb39 100644 --- a/sys/kern/kern_exec.c +++ b/sys/kern/kern_exec.c @@ -1,4 +1,4 @@ -/* $OpenBSD: kern_exec.c,v 1.67 2002/05/02 00:36:04 millert Exp $ */ +/* $OpenBSD: kern_exec.c,v 1.68 2002/07/20 19:24:57 art Exp $ */ /* $NetBSD: kern_exec.c,v 1.75 1996/02/09 18:59:28 christos Exp $ */ /*- @@ -66,6 +66,11 @@ #include <dev/rndvar.h> /* + * Map the shared signal code. + */ +int exec_sigcode_map(struct proc *, struct emul *); + +/* * stackgap_random specifies if the stackgap should have a random size added * to it. Must be a n^2. If non-zero, the stack gap will be calculated as: * (arc4random() * ALIGNBYTES) & (stackgap_random - 1) + STACKGAPLEN. @@ -246,7 +251,6 @@ sys_execve(p, v, retval) struct ps_strings arginfo; struct vmspace *vm = p->p_vmspace; char **tmpfap; - int szsigcode; extern struct emul emul_native; /* @@ -365,15 +369,12 @@ sys_execve(p, v, retval) dp = (char *)ALIGN(dp); - szsigcode = pack.ep_emul->e_esigcode - pack.ep_emul->e_sigcode; - sgap = STACKGAPLEN; if (stackgap_random != 0) sgap += (arc4random() * ALIGNBYTES) & (stackgap_random - 1); /* Now check if args & environ fit into new stack */ len = ((argc + envc + 2 + pack.ep_emul->e_arglen) * sizeof(char *) + - sizeof(long) + dp + sgap + szsigcode + - sizeof(struct ps_strings)) - argp; + sizeof(long) + dp + sgap + sizeof(struct ps_strings)) - argp; len = ALIGN(len); /* make the stack "safely" aligned */ @@ -424,8 +425,8 @@ sys_execve(p, v, retval) arginfo.ps_nenvstr = envc; #ifdef MACHINE_STACK_GROWS_UP - stack = (char *)USRSTACK + sizeof(arginfo) + szsigcode; - slen = len - sizeof(arginfo) - szsigcode; + stack = (char *)USRSTACK + sizeof(arginfo); + slen = len - sizeof(arginfo); #else stack = (char *)(USRSTACK - len); #endif @@ -437,17 +438,6 @@ sys_execve(p, v, retval) if (copyout(&arginfo, (char *)PS_STRINGS, sizeof(arginfo))) goto exec_abort; - /* copy out the process's signal trampoline code */ -#ifdef MACHINE_STACK_GROWS_UP - if (szsigcode && copyout((char *)pack.ep_emul->e_sigcode, - ((char *)PS_STRINGS) + sizeof(arginfo), szsigcode)) - goto exec_abort; -#else - if (szsigcode && copyout((char *)pack.ep_emul->e_sigcode, - ((char *)PS_STRINGS) - szsigcode, szsigcode)) - goto exec_abort; -#endif - stopprofclock(p); /* stop profiling */ fdcloseexec(p); /* handle close on exec */ execsigs(p); /* reset catched signals */ @@ -607,6 +597,10 @@ sys_execve(p, v, retval) (*pack.ep_emul->e_setregs)(p, &pack, (u_long)stack, retval); #endif + /* map the process's signal trampoline code */ + if (exec_sigcode_map(p, pack.ep_emul)) + goto exec_abort; + if (p->p_flag & P_TRACED) psignal(p, SIGTRAP); @@ -708,3 +702,52 @@ copyargs(pack, arginfo, stack, argp) return (cpp); } + +int +exec_sigcode_map(struct proc *p, struct emul *e) +{ + vsize_t sz; + + sz = (vaddr_t)e->e_esigcode - (vaddr_t)e->e_sigcode; + + /* + * If we don't have a sigobject for this emulation, create one. + * + * sigobject is an anonymous memory object (just like SYSV shared + * memory) that we keep a permanent reference to and that we map + * in all processes that need this sigcode. The creation is simple, + * we create an object, add a permanent reference to it, map it in + * kernel space, copy out the sigcode to it and unmap it. + * The we map it with PROT_READ|PROT_EXEC into the process just + * the way sys_mmap would map it. + */ + if (e->e_sigobject == NULL) { + vaddr_t va; + int r; + + e->e_sigobject = uao_create(sz, 0); + uao_reference(e->e_sigobject); /* permanent reference */ + + va = vm_map_min(kernel_map); /* hint */ + if ((r = uvm_map(kernel_map, &va, round_page(sz), e->e_sigobject, + 0, 0, UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, + UVM_INH_SHARE, UVM_ADV_RANDOM, 0)))) { + printf("kernel mapping failed %d\n", r); + return (ENOMEM); + } + memcpy((void *)va, e->e_sigcode, sz); + uvm_unmap(kernel_map, va, va + round_page(sz)); + } + + /* Just a hint to uvm_mmap where to put it. */ + p->p_sigcode = round_page((vaddr_t)p->p_vmspace->vm_daddr + MAXDSIZ); + uao_reference(e->e_sigobject); + if (uvm_map(&p->p_vmspace->vm_map, &p->p_sigcode, round_page(sz), + e->e_sigobject, 0, 0, UVM_MAPFLAG(UVM_PROT_RX, UVM_PROT_RX, + UVM_INH_SHARE, UVM_ADV_RANDOM, 0))) { + printf("user mapping failed\n"); + return (ENOMEM); + } + + return (0); +} |