openkylin
/
qemu
mirror of https://gitee.com/openkylin/qemu.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

exec: Fix bounce buffer allocation in address_space_map() 

This fixes a regression introduced by commit e3127ae0c, which kept the
allocation size of the bounce buffer limited to one page in order to
avoid unbounded allocations (as explained in the commit message of
6d16c2f88), but broke the reporting of the shortened bounce buffer to
the caller. The caller therefore assumes that the full requested size
was provided and causes memory corruption when writing beyond the end of
the actually allocated buffer.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2013-07-22 14:30:23 +02:00
parent ba2ab2f2ca
commit e85d9db5f6
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
exec.c
View File

@ -2099,7 +2099,9 @@ void *address_space_map(AddressSpace *as,
if (bounce.buffer) {
return NULL;
}
bounce.buffer = qemu_memalign(TARGET_PAGE_SIZE, TARGET_PAGE_SIZE);
/* Avoid unbounded allocations */
l = MIN(l, TARGET_PAGE_SIZE);
bounce.buffer = qemu_memalign(TARGET_PAGE_SIZE, l);
bounce.addr = addr;
bounce.len = l;