[fix] mappages: potential memory leak #118
Open
+6
−3
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In mappages, if
size
> 1 *PAGESIZE
orva
not page-aligned(i.e. need to map more than one page), it will lead to a memory leak with a midwaykalloc
failure. When mappages returns -1, it will try to calluvmfree
->freewalk
to free the page-table pages and may lead to a panic because of an mapped page.In the unmodified version, maapages always successes or is only called with 1 *
PAGESIZE
, so this problem doesn't rise.