xen: mapcache: Fix unmapping of first entries in buckets

This fixes the clobbering of the entry->next pointer when
unmapping the first entry in a bucket of a mapcache.

Fixes: 123acd816d ("xen: mapcache: Unmap first entries in buckets")
Reported-by: Anthony PERARD <anthony.perard@vates.tech>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
This commit is contained in:
Edgar E. Iglesias 2024-07-02 00:44:21 +02:00
parent 596ccccdbf
commit 872cb9cced

View File

@ -597,7 +597,17 @@ static void xen_invalidate_map_cache_entry_unlocked(MapCache *mc,
pentry->next = entry->next;
g_free(entry);
} else {
memset(entry, 0, sizeof *entry);
/*
* Invalidate mapping but keep entry->next pointing to the rest
* of the list.
*
* Note that lock is already zero here, otherwise we don't unmap.
*/
entry->paddr_index = 0;
entry->vaddr_base = NULL;
entry->valid_mapping = NULL;
entry->flags = 0;
entry->size = 0;
}
}