diff options
Diffstat (limited to 'sys/amd64')
| -rw-r--r-- | sys/amd64/linux32/linux.h | 9 | ||||
| -rw-r--r-- | sys/amd64/linux32/linux32_machdep.c | 102 |
2 files changed, 51 insertions, 60 deletions
diff --git a/sys/amd64/linux32/linux.h b/sys/amd64/linux32/linux.h index ff8680ae..b7d071e 100644 --- a/sys/amd64/linux32/linux.h +++ b/sys/amd64/linux32/linux.h @@ -167,6 +167,15 @@ struct l_rusage { #define LINUX_MAP_ANON 0x0020 #define LINUX_MAP_GROWSDOWN 0x0100 +struct l_mmap_argv { + l_uintptr_t addr; + l_size_t len; + l_int prot; + l_int flags; + l_int fd; + l_off_t pgoff; +} __packed; + /* * stat family of syscalls */ diff --git a/sys/amd64/linux32/linux32_machdep.c b/sys/amd64/linux32/linux32_machdep.c index 1f49458..53ad3d4 100644 --- a/sys/amd64/linux32/linux32_machdep.c +++ b/sys/amd64/linux32/linux32_machdep.c @@ -690,16 +690,6 @@ linux_clone(struct thread *td, struct linux_clone_args *args) return (0); } -/* XXX move */ -struct l_mmap_argv { - l_ulong addr; - l_ulong len; - l_ulong prot; - l_ulong flags; - l_ulong fd; - l_ulong pgoff; -}; - #define STACK_SIZE (2 * 1024 * 1024) #define GUARD_SIZE (4 * PAGE_SIZE) @@ -789,9 +779,44 @@ linux_mmap_common(struct thread *td, struct l_mmap_argv *linux_args) bsd_args.flags |= MAP_ANON; else bsd_args.flags |= MAP_NOSYNC; - if (linux_args->flags & LINUX_MAP_GROWSDOWN) { + if (linux_args->flags & LINUX_MAP_GROWSDOWN) bsd_args.flags |= MAP_STACK; + /* + * PROT_READ, PROT_WRITE, or PROT_EXEC implies PROT_READ and PROT_EXEC + * on Linux/i386. We do this to ensure maximum compatibility. + * Linux/ia64 does the same in i386 emulation mode. + */ + bsd_args.prot = linux_args->prot; + if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC)) + bsd_args.prot |= PROT_READ | PROT_EXEC; + + if (linux_args->fd != -1) { + /* + * Linux follows Solaris mmap(2) description: + * The file descriptor fildes is opened with + * read permission, regardless of the + * protection options specified. + */ + + if ((error = fget(td, linux_args->fd, &fp)) != 0) + return (error); + if (fp->f_type != DTYPE_VNODE) { + fdrop(fp, td); + return (EINVAL); + } + + /* Linux mmap() just fails for O_WRONLY files */ + if (!(fp->f_flag & FREAD)) { + fdrop(fp, td); + return (EACCES); + } + + fdrop(fp, td); + } + bsd_args.fd = linux_args->fd; + + if (linux_args->flags & LINUX_MAP_GROWSDOWN) { /* * The linux MAP_GROWSDOWN option does not limit auto * growth of the region. Linux mmap with this option @@ -814,11 +839,7 @@ linux_mmap_common(struct thread *td, struct l_mmap_argv *linux_args) * fixed size of (STACK_SIZE - GUARD_SIZE). */ - /* This gives us TOS */ - bsd_args.addr = (caddr_t)PTRIN(linux_args->addr) + - linux_args->len; - - if ((caddr_t)PTRIN(bsd_args.addr) > + if ((caddr_t)PTRIN(linux_args->addr) + linux_args->len > p->p_vmspace->vm_maxsaddr) { /* * Some linux apps will attempt to mmap @@ -837,8 +858,7 @@ linux_mmap_common(struct thread *td, struct l_mmap_argv *linux_args) * mmap's return value. */ PROC_LOCK(p); - p->p_vmspace->vm_maxsaddr = - (char *)LINUX32_USRSTACK - + p->p_vmspace->vm_maxsaddr = (char *)LINUX32_USRSTACK - lim_cur(p, RLIMIT_STACK); PROC_UNLOCK(p); } @@ -856,49 +876,12 @@ linux_mmap_common(struct thread *td, struct l_mmap_argv *linux_args) * not using VM_STACK we map the full stack, since we * don't have a way to autogrow it. */ - bsd_args.addr -= bsd_args.len; + bsd_args.addr = (caddr_t)PTRIN(linux_args->addr) - + bsd_args.len; } else { bsd_args.addr = (caddr_t)PTRIN(linux_args->addr); bsd_args.len = linux_args->len; } - - /* - * We add PROT_EXEC to work around buggy applications (e.g. Java) - * that take advantage of the fact that execute permissions are not - * enforced by x86 CPUs. - */ - bsd_args.prot = linux_args->prot | PROT_EXEC; - if (linux_args->flags & LINUX_MAP_ANON) - bsd_args.fd = -1; - else { - /* - * Linux follows Solaris mmap(2) description: - * The file descriptor fildes is opened with - * read permission, regardless of the - * protection options specified. - * If PROT_WRITE is specified, the application - * must have opened the file descriptor - * fildes with write permission unless - * MAP_PRIVATE is specified in the flag - * argument as described below. - */ - - if ((error = fget(td, linux_args->fd, &fp)) != 0) - return (error); - if (fp->f_type != DTYPE_VNODE) { - fdrop(fp, td); - return (EINVAL); - } - - /* Linux mmap() just fails for O_WRONLY files */ - if (! (fp->f_flag & FREAD)) { - fdrop(fp, td); - return (EACCES); - } - - bsd_args.fd = linux_args->fd; - fdrop(fp, td); - } bsd_args.pos = (off_t)linux_args->pgoff * PAGE_SIZE; bsd_args.pad = 0; @@ -1181,8 +1164,7 @@ linux_mprotect(struct thread *td, struct linux_mprotect_args *uap) bsd_args.addr = uap->addr; bsd_args.len = uap->len; bsd_args.prot = uap->prot; - /* XXX PROT_READ implies PROT_EXEC; see linux_mmap_common(). */ - if ((bsd_args.prot & PROT_READ) != 0) - bsd_args.prot |= PROT_EXEC; + if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC)) + bsd_args.prot |= PROT_READ | PROT_EXEC; return (mprotect(td, &bsd_args)); } |
