Author: brooks Date: Wed Mar 4 21:27:12 2020 New Revision: 358650 URL: https://svnweb.freebsd.org/changeset/base/358650
Log: Introduce kern_mmap_req(). This presents an extensible interface to the generic mmap(2) implementation via a struct pointer intended to use a designated initializer or compount literal. We take advantage of the mandatory zeroing of fields not listed in the initializer. Remove kern_mmap_fpcheck() and use kern_mmap_req(). The motivation for this change is a desire to keep the core implementation from growing an ever-increasing number of arguments that must be specified in the correct order for the lowest-level implementations. In CheriBSD we have already added two more arguments. Reviewed by: kib Discussed with: kevans Obtained from: CheriBSD Sponsored by: DARPA, AFRL Differential Revision: https://reviews.freebsd.org/D23164 Modified: head/sys/compat/linux/linux_mmap.c head/sys/sys/syscallsubr.h head/sys/vm/vm_mmap.c Modified: head/sys/compat/linux/linux_mmap.c ============================================================================== --- head/sys/compat/linux/linux_mmap.c Wed Mar 4 21:25:48 2020 (r358649) +++ head/sys/compat/linux/linux_mmap.c Wed Mar 4 21:27:12 2020 (r358650) @@ -77,6 +77,7 @@ int linux_mmap_common(struct thread *td, uintptr_t addr, size_t len, int prot, int flags, int fd, off_t pos) { + struct mmap_req mr, mr_fixed; struct proc *p = td->td_proc; struct vmspace *vms = td->td_proc->p_vmspace; int bsd_flags, error; @@ -201,17 +202,25 @@ linux_mmap_common(struct thread *td, uintptr_t addr, s * address is not zero, try with MAP_FIXED and MAP_EXCL first, * and fall back to the normal behaviour if that fails. */ + mr = (struct mmap_req) { + .mr_hint = addr, + .mr_len = len, + .mr_prot = prot, + .mr_flags = bsd_flags, + .mr_fd = fd, + .mr_pos = pos, + .mr_check_fp_fn = linux_mmap_check_fp, + }; if (addr != 0 && (bsd_flags & MAP_FIXED) == 0 && (bsd_flags & MAP_EXCL) == 0) { - error = kern_mmap_fpcheck(td, addr, len, prot, - bsd_flags | MAP_FIXED | MAP_EXCL, fd, pos, - linux_mmap_check_fp); + mr_fixed = mr; + mr_fixed.mr_flags |= MAP_FIXED | MAP_EXCL; + error = kern_mmap_req(td, &mr_fixed); if (error == 0) goto out; } - error = kern_mmap_fpcheck(td, addr, len, prot, bsd_flags, fd, pos, - linux_mmap_check_fp); + error = kern_mmap_req(td, &mr); out: LINUX_CTR2(mmap2, "return: %d (%p)", error, td->td_retval[0]); Modified: head/sys/sys/syscallsubr.h ============================================================================== --- head/sys/sys/syscallsubr.h Wed Mar 4 21:25:48 2020 (r358649) +++ head/sys/sys/syscallsubr.h Wed Mar 4 21:27:12 2020 (r358650) @@ -65,6 +65,18 @@ struct uio; typedef int (*mmap_check_fp_fn)(struct file *, int, int, int); +struct mmap_req { + vm_offset_t mr_hint; + vm_size_t mr_len; + int mr_prot; + int mr_flags; + int mr_fd; + off_t mr_pos; + mmap_check_fp_fn mr_check_fp_fn; +}; + +int kern___getcwd(struct thread *td, char *buf, enum uio_seg bufseg, + size_t buflen, size_t path_max); int kern_accept(struct thread *td, int s, struct sockaddr **name, socklen_t *namelen, struct file **fp); int kern_accept4(struct thread *td, int s, struct sockaddr **name, @@ -182,9 +194,7 @@ int kern_mlock(struct proc *proc, struct ucred *cred, size_t len); int kern_mmap(struct thread *td, uintptr_t addr, size_t len, int prot, int flags, int fd, off_t pos); -int kern_mmap_fpcheck(struct thread *td, uintptr_t addr, size_t len, - int prot, int flags, int fd, off_t pos, - mmap_check_fp_fn check_fp_fn); +int kern_mmap_req(struct thread *td, const struct mmap_req *mrp); int kern_mmap_maxprot(struct proc *p, int prot); int kern_mprotect(struct thread *td, uintptr_t addr, size_t size, int prot); int kern_msgctl(struct thread *, int, int, struct msqid_ds *); Modified: head/sys/vm/vm_mmap.c ============================================================================== --- head/sys/vm/vm_mmap.c Wed Mar 4 21:25:48 2020 (r358649) +++ head/sys/vm/vm_mmap.c Wed Mar 4 21:27:12 2020 (r358650) @@ -199,27 +199,40 @@ int kern_mmap(struct thread *td, uintptr_t addr0, size_t len, int prot, int flags, int fd, off_t pos) { + struct mmap_req mr = { + .mr_hint = addr0, + .mr_len = len, + .mr_prot = prot, + .mr_flags = flags, + .mr_fd = fd, + .mr_pos = pos + }; - return (kern_mmap_fpcheck(td, addr0, len, prot, flags, fd, pos, NULL)); + return (kern_mmap_req(td, &mr)); } -/* - * When mmap'ing a file, check_fp_fn may be used for the caller to do any - * last-minute validation based on the referenced file in a non-racy way. - */ int -kern_mmap_fpcheck(struct thread *td, uintptr_t addr0, size_t len, int prot, - int flags, int fd, off_t pos, mmap_check_fp_fn check_fp_fn) +kern_mmap_req(struct thread *td, const struct mmap_req *mrp) { struct vmspace *vms; struct file *fp; struct proc *p; + off_t pos; vm_offset_t addr; - vm_size_t pageoff, size; + vm_size_t len, pageoff, size; vm_prot_t cap_maxprot; - int align, error, max_prot; + int align, error, fd, flags, max_prot, prot; cap_rights_t rights; + mmap_check_fp_fn check_fp_fn; + addr = mrp->mr_hint; + len = mrp->mr_len; + prot = mrp->mr_prot; + flags = mrp->mr_flags; + fd = mrp->mr_fd; + pos = mrp->mr_pos; + check_fp_fn = mrp->mr_check_fp_fn; + if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) return (EINVAL); max_prot = PROT_MAX_EXTRACT(prot); @@ -239,7 +252,6 @@ kern_mmap_fpcheck(struct thread *td, uintptr_t addr0, vms = p->p_vmspace; fp = NULL; AUDIT_ARG_FD(fd); - addr = addr0; /* * Ignore old flags that used to be defined but did not do anything. _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
