Commit adb2a9b5 authored by Tyler Hall's avatar Tyler Hall Committed by Stefan Hajnoczi
Browse files

exec.c: Fix off-by-one error in register_subpage



subpage_register() expects "end" to be the last byte in the mapping.
Registering a non-page-aligned memory region that extends up to or
beyond a page boundary causes subpage_register() to silently fail
through the (end >= PAGE_SIZE) check.

This bug does not cause noticeable problems for mappings that do not
extend to a page boundary, though they do register an extra byte.
Signed-off-by: default avatarTyler Hall <tylerwhall@gmail.com>
Reviewed-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: default avatarAvi Kivity <avi@redhat.com>
Signed-off-by: default avatarStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
parent 8715fc1e
......@@ -2271,7 +2271,7 @@ static void register_subpage(MemoryRegionSection *section)
subpage = container_of(existing->mr, subpage_t, iomem);
}
start = section->offset_within_address_space & ~TARGET_PAGE_MASK;
end = start + section->size;
end = start + section->size - 1;
subpage_register(subpage, start, end, phys_section_add(section));
}
......
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