d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Do not use pmap_kextract() to find out the physical address of a user

Browse Source 
belong to a user virtual address; while this happens to work on some
architectures, it can't on sparc64, since user and kernel virtual
address spaces overlap there (the distinction between them is done via
separate address space identifiers).

Instead, look up the page in the vm_map of the process in question.

Reviewed by:	jake
This commit is contained in:
tmm 2002-04-12 19:38:41 +00:00
parent 389e1779ff
commit 1720bac84c
1 changed files with 17 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
sys/kern/sys_pipe.c
View File

@ -599,9 +599,16 @@ pipe_build_write_buffer(wpipe, uio)
struct pipe *wpipe;
struct uio *uio;
{
vm_map_t map;
vm_map_entry_t me;
vm_object_t obj;
vm_pindex_t pidx;
vm_prot_t prot;
vm_page_t m;
boolean_t wired;
u_int size;
int i;
vm_offset_t addr, endaddr, paddr;
int i, rv;
vm_offset_t addr, endaddr;
GIANT_REQUIRED;
PIPE_LOCK_ASSERT(wpipe, MA_NOTOWNED);
@ -613,19 +620,23 @@ pipe_build_write_buffer(wpipe, uio)
endaddr = round_page((vm_offset_t)uio->uio_iov->iov_base + size);
addr = trunc_page((vm_offset_t)uio->uio_iov->iov_base);
for (i = 0; addr < endaddr; addr += PAGE_SIZE, i++) {
vm_page_t m;
map = &curproc->p_vmspace->vm_map;
rv = KERN_FAILURE;
if (vm_fault_quick((caddr_t)addr, VM_PROT_READ) < 0 ||
(paddr = pmap_kextract(addr)) == 0) {
(rv = vm_map_lookup(&map, addr, VM_PROT_READ, &me, &obj,
&pidx, &prot, &wired)) != KERN_SUCCESS ||
(m = vm_page_lookup(obj, pidx)) == NULL) {
int j;
if (rv == KERN_SUCCESS)
vm_map_lookup_done(map, me);
for (j = 0; j < i; j++)
vm_page_unwire(wpipe->pipe_map.ms[j], 1);
return (EFAULT);
}
m = PHYS_TO_VM_PAGE(paddr);
vm_page_wire(m);
vm_map_lookup_done(map, me);
wpipe->pipe_map.ms[i] = m;
}