From: Ben Hutchings ben@decadent.org.uk
[ Upstream commit 7c5d4801ecf0564c860033d89726b99723c55146 ]
irq_cpu_rmap_release() calls cpu_rmap_put(), which may free the rmap. So we need to clear the pointer to our glue structure in rmap before doing that, not after.
Fixes: 4e0473f1060a ("lib: cpu_rmap: Avoid use after free on rmap->obj array entries") Signed-off-by: Ben Hutchings ben@decadent.org.uk Reviewed-by: Simon Horman simon.horman@corigine.com Link: https://lore.kernel.org/r/ZHo0vwquhOy3FaXc@decadent.org.uk Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- lib/cpu_rmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/cpu_rmap.c b/lib/cpu_rmap.c index 920403fa5b0de..51621fde0b488 100644 --- a/lib/cpu_rmap.c +++ b/lib/cpu_rmap.c @@ -268,8 +268,8 @@ static void irq_cpu_rmap_release(struct kref *ref) struct irq_glue *glue = container_of(ref, struct irq_glue, notify.kref);
- cpu_rmap_put(glue->rmap); glue->rmap->obj[glue->index] = NULL; + cpu_rmap_put(glue->rmap); kfree(glue); }