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Diffstat (limited to 'winsup/cygwin/mmap.cc')
-rw-r--r--winsup/cygwin/mmap.cc91
1 files changed, 59 insertions, 32 deletions
diff --git a/winsup/cygwin/mmap.cc b/winsup/cygwin/mmap.cc
index 6cf8cc7df8f..08f89c84f4c 100644
--- a/winsup/cygwin/mmap.cc
+++ b/winsup/cygwin/mmap.cc
@@ -13,7 +13,6 @@ details. */
#include <stdlib.h>
#include <stddef.h>
#include <sys/mman.h>
-#include <errno.h>
#include "security.h"
#include "path.h"
#include "fhandler.h"
@@ -272,7 +271,8 @@ public:
void erase (int i);
void erase ();
mmap_record *match (_off64_t off, DWORD len);
- long match (caddr_t addr, DWORD len, long start);
+ long match (caddr_t addr, DWORD len, caddr_t &m_addr, DWORD &m_len,
+ long start);
};
list::list ()
@@ -325,13 +325,24 @@ list::match (_off64_t off, DWORD len)
/* Used in munmap() */
long
-list::match (caddr_t addr, DWORD len, _off_t start)
+list::match (caddr_t addr, DWORD len, caddr_t &m_addr, DWORD &m_len,
+ _off_t start)
{
+ caddr_t low, high;
+
for (int i = start + 1; i < nrecs; ++i)
- if (addr >= recs[i].get_address ()
- && addr + len <= recs[i].get_address ()
- + (PAGE_CNT (recs[i].get_size ()) * getpagesize ()))
- return i;
+ {
+ low = (addr >= recs[i].get_address ()) ? addr : recs[i].get_address ();
+ high = recs[i].get_address ()
+ + (PAGE_CNT (recs[i].get_size ()) * getpagesize ());
+ high = (addr + len < high) ? addr + len : high;
+ if (low < high)
+ {
+ m_addr = low;
+ m_len = high - low;
+ return i;
+ }
+ }
return -1;
}
@@ -440,7 +451,7 @@ mmap64 (caddr_t addr, size_t len, int prot, int flags, int fd, _off64_t off)
if (off % getpagesize ()
|| (!(flags & MAP_SHARED) && !(flags & MAP_PRIVATE))
|| ((flags & MAP_SHARED) && (flags & MAP_PRIVATE))
- || ((flags & MAP_FIXED) && ((DWORD)addr % granularity))
+ || ((flags & MAP_FIXED) && ((DWORD)addr % getpagesize ()))
|| !len)
{
set_errno (EINVAL);
@@ -471,8 +482,6 @@ mmap64 (caddr_t addr, size_t len, int prot, int flags, int fd, _off64_t off)
DWORD gran_len = howmany (off + len, granularity) * granularity - gran_off;
fhandler_base *fh;
- caddr_t base = addr;
- HANDLE h;
if (fd != -1)
{
@@ -490,6 +499,16 @@ mmap64 (caddr_t addr, size_t len, int prot, int flags, int fd, _off64_t off)
DWORD high;
DWORD low = GetFileSize (fh->get_handle (), &high);
_off64_t fsiz = ((_off64_t)high << 32) + low;
+ /* Don't allow mappings beginning beyond EOF since Windows can't
+ handle that POSIX like. FIXME: Still looking for a good idea
+ to allow that nevertheless. */
+ if (gran_off >= fsiz)
+ {
+ set_errno (ENXIO);
+ ReleaseResourceLock (LOCK_MMAP_LIST, READ_LOCK | WRITE_LOCK,
+ "mmap");
+ return MAP_FAILED;
+ }
fsiz -= gran_off;
if (gran_len > fsiz)
gran_len = fsiz;
@@ -542,7 +561,13 @@ mmap64 (caddr_t addr, size_t len, int prot, int flags, int fd, _off64_t off)
&& (wincap.has_working_copy_on_write () || fd != -1))
access = FILE_MAP_COPY;
- h = fh->mmap (&base, gran_len, access, flags, gran_off);
+ caddr_t base = addr;
+ /* This shifts the base address to the next lower 64K boundary.
+ The offset is re-added when evaluating the return value. */
+ if (base)
+ base -= off - gran_off;
+
+ HANDLE h = fh->mmap (&base, gran_len, access, flags, gran_off);
if (h == INVALID_HANDLE_VALUE)
{
@@ -589,16 +614,16 @@ mmap (caddr_t addr, size_t len, int prot, int flags, int fd, _off_t off)
return mmap64 (addr, len, prot, flags, fd, (_off64_t)off);
}
-/* munmap () removes an mmapped area. It insists that base area
- requested is the same as that mmapped, error if not. */
+/* munmap () removes all mmapped pages between addr and addr+len. */
extern "C" int
munmap (caddr_t addr, size_t len)
{
syscall_printf ("munmap (addr %x, len %d)", addr, len);
- /* Error conditions according to SUSv2 */
- if (((DWORD)addr % getpagesize ()) || !len)
+ /* Error conditions according to SUSv3 */
+ if (!addr || ((DWORD)addr % getpagesize ()) || !len
+ || IsBadReadPtr (addr, len))
{
set_errno (EINVAL);
syscall_printf ("-1 = munmap(): Invalid parameters");
@@ -606,17 +631,15 @@ munmap (caddr_t addr, size_t len)
}
SetResourceLock (LOCK_MMAP_LIST, WRITE_LOCK | READ_LOCK, "munmap");
- /* Check if a mmap'ed area was ever created */
if (mmapped_areas == NULL)
{
syscall_printf ("-1 = munmap(): mmapped_areas == NULL");
- set_errno (EINVAL);
ReleaseResourceLock (LOCK_MMAP_LIST, WRITE_LOCK | READ_LOCK, "munmap");
- return -1;
+ return 0;
}
- /* Iterate through the map, looking for the mmapped area.
- Error if not found. */
+ /* Iterate through the map, unmap pages between addr and addr+len
+ in all maps. */
for (int it = 0; it < mmapped_areas->nlists; ++it)
{
@@ -624,10 +647,13 @@ munmap (caddr_t addr, size_t len)
if (map_list)
{
long li = -1;
- if ((li = map_list->match(addr, len, li)) >= 0)
+ caddr_t u_addr;
+ DWORD u_len;
+
+ while ((li = map_list->match(addr, len, u_addr, u_len, li)) >= 0)
{
mmap_record *rec = map_list->recs + li;
- if (rec->unmap_map (addr, len))
+ if (rec->unmap_map (u_addr, u_len))
{
fhandler_base *fh = rec->alloc_fh ();
fh->munmap (rec->get_handle (), addr, len);
@@ -636,18 +662,13 @@ munmap (caddr_t addr, size_t len)
/* Delete the entry. */
map_list->erase (li);
}
- syscall_printf ("0 = munmap(): %x", addr);
- ReleaseResourceLock (LOCK_MMAP_LIST, WRITE_LOCK | READ_LOCK, "munmap");
- return 0;
}
}
}
- set_errno (EINVAL);
- syscall_printf ("-1 = munmap(): EINVAL");
-
ReleaseResourceLock (LOCK_MMAP_LIST, WRITE_LOCK | READ_LOCK, "munmap");
- return -1;
+ syscall_printf ("0 = munmap(): %x", addr);
+ return 0;
}
/* Sync file with memory. Ignore flags for now. */
@@ -815,9 +836,15 @@ fhandler_disk_file::mmap (caddr_t *addr, size_t len, DWORD access,
}
DWORD high = off >> 32, low = off & 0xffffffff;
- void *base = MapViewOfFileEx (h, access, high, low, len,
- (flags & MAP_FIXED) ? *addr : NULL);
- debug_printf ("%x = MapViewOfFileEx (h:%x, access:%x, 0, off:%D, len:%d, addr:%x)", base, h, access, off, len, (flags & MAP_FIXED) ? *addr : NULL);
+ void *base = NULL;
+ /* If a non-zero address is given, try mapping using the given address first.
+ If it fails and flags is not MAP_FIXED, try again with NULL address. */
+ if (*addr)
+ base = MapViewOfFileEx (h, access, high, low, len, *addr);
+ if (!base && !(flags & MAP_FIXED))
+ base = MapViewOfFileEx (h, access, high, low, len, NULL);
+ debug_printf ("%x = MapViewOfFileEx (h:%x, access:%x, 0, off:%D, "
+ "len:%d, addr:%x)", base, h, access, off, len, *addr);
if (!base || ((flags & MAP_FIXED) && base != *addr))
{
if (!base)
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