diff options
Diffstat (limited to 'sys/kern/sys_process.c')
| -rw-r--r-- | sys/kern/sys_process.c | 131 |
1 files changed, 109 insertions, 22 deletions
diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c index 7225a63328b4..023d61d4346c 100644 --- a/sys/kern/sys_process.c +++ b/sys/kern/sys_process.c @@ -33,6 +33,7 @@ #include <sys/param.h> #include <sys/systm.h> +#include <sys/imgact.h> #include <sys/ktr.h> #include <sys/limits.h> #include <sys/lock.h> @@ -333,25 +334,93 @@ proc_sstep(struct thread *td) return (ptrace_single_step(td)); } +static int +proc_vmspace_check_access(struct thread *td, struct proc *p, int flags) +{ + PROC_ASSERT_HELD(p); + if ((flags & PRVM_CHECK_DEBUG) != 0) + return (p_candebug(td, p)); + if ((flags & PRVM_CHECK_VISIBILITY) != 0) + return (p_cansee(td, p)); + return (0); +} + int -proc_rwmem(struct proc *p, struct uio *uio) +proc_vmspace_ref(struct thread *td, struct proc *p, int flags, + struct vmspace **vmp) +{ + struct vmspace *vm; + int error; + + MPASS((flags & ~(PRVM_BLOCK_EXEC | PRVM_CHECK_VISIBILITY | + PRVM_CHECK_DEBUG)) == 0); + MPASS((flags & (PRVM_CHECK_VISIBILITY | PRVM_CHECK_DEBUG)) != + (PRVM_CHECK_VISIBILITY | PRVM_CHECK_DEBUG)); + + PROC_LOCK(p); + if (p != td->td_proc) { + PROC_ASSERT_HELD(p); + + /* + * Make sure that the vmspace doesn't switch out from + * under us. + */ + if ((flags & PRVM_BLOCK_EXEC) != 0) { + for (;;) { + if (!execve_block(td, p)) { + PROC_LOCK(p); + continue; + } + error = proc_vmspace_check_access(td, p, flags); + if (error != 0) { + execve_unblock(td, p); + PROC_UNLOCK(p); + return (error); + } + break; + } + } else { + error = proc_vmspace_check_access(td, p, flags); + if (error != 0) { + PROC_UNLOCK(p); + return (error); + } + } + } + vm = vmspace_acquire_ref(p); + if (vm == NULL) { + if (p != td->td_proc && (flags & PRVM_BLOCK_EXEC) != 0) + execve_unblock(td, p); + PROC_UNLOCK(p); + return (ESRCH); + } + PROC_UNLOCK(p); + *vmp = vm; + return (0); +} + +void +proc_vmspace_unref(struct thread *td, struct proc *p, int flags, + struct vmspace *vm) +{ + vmspace_free(vm); + if (p != td->td_proc && (flags & PRVM_BLOCK_EXEC) != 0) { + PROC_LOCK(p); + PROC_ASSERT_HELD(p); + execve_unblock(td, p); + PROC_UNLOCK(p); + } +} + +static int +vmspace_rwmem(struct vmspace *vm, struct uio *uio) { vm_map_t map; vm_offset_t pageno; /* page number */ vm_prot_t reqprot; int error, fault_flags, page_offset, writing; - /* - * Make sure that the process' vmspace remains live. - */ - if (p != curproc) - PROC_ASSERT_HELD(p); - PROC_LOCK_ASSERT(p, MA_NOTOWNED); - - /* - * The map we want... - */ - map = &p->p_vmspace->vm_map; + map = &vm->vm_map; /* * If we are writing, then we request vm_fault() to create a private @@ -363,9 +432,9 @@ proc_rwmem(struct proc *p, struct uio *uio) fault_flags = writing ? VM_FAULT_DIRTY : VM_FAULT_NORMAL; if (writing) { - error = priv_check_cred(p->p_ucred, PRIV_PROC_MEM_WRITE); - if (error) - return (error); + error = priv_check(curthread, PRIV_PROC_MEM_WRITE); + if (error != 0) + goto out; } /* @@ -423,16 +492,34 @@ proc_rwmem(struct proc *p, struct uio *uio) } while (error == 0 && uio->uio_resid > 0); +out: return (error); } -static ssize_t -proc_iop(struct thread *td, struct proc *p, vm_offset_t va, void *buf, +int +proc_rwmem(struct proc *p, struct uio *uio, int flags) +{ + struct vmspace *vm; + struct thread *td; + int error; + + td = curthread; + error = proc_vmspace_ref(td, p, flags, &vm); + if (error != 0) + return (error); + error = vmspace_rwmem(vm, uio); + proc_vmspace_unref(td, p, flags, vm); + return (error); +} + +ssize_t +vmspace_iop(struct thread *td, struct vmspace *vm, vm_offset_t va, void *buf, size_t len, enum uio_rw rw) { struct iovec iov; struct uio uio; ssize_t slen; + int error; MPASS(len < SSIZE_MAX); slen = (ssize_t)len; @@ -446,8 +533,8 @@ proc_iop(struct thread *td, struct proc *p, vm_offset_t va, void *buf, uio.uio_segflg = UIO_SYSSPACE; uio.uio_rw = rw; uio.uio_td = td; - proc_rwmem(p, &uio); - if (uio.uio_resid == slen) + error = vmspace_rwmem(vm, &uio); + if (error != 0 || uio.uio_resid == slen) return (-1); return (slen - uio.uio_resid); } @@ -457,7 +544,7 @@ proc_readmem(struct thread *td, struct proc *p, vm_offset_t va, void *buf, size_t len) { - return (proc_iop(td, p, va, buf, len, UIO_READ)); + return (vmspace_iop(td, p->p_vmspace, va, buf, len, UIO_READ)); } ssize_t @@ -465,7 +552,7 @@ proc_writemem(struct thread *td, struct proc *p, vm_offset_t va, void *buf, size_t len) { - return (proc_iop(td, p, va, buf, len, UIO_WRITE)); + return (vmspace_iop(td, p->p_vmspace, va, buf, len, UIO_WRITE)); } static int @@ -1458,7 +1545,7 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) goto out; } PROC_UNLOCK(p); - error = proc_rwmem(p, &uio); + error = proc_rwmem(p, &uio, 0); piod->piod_len -= uio.uio_resid; PROC_LOCK(p); break; |