From e78759ba4d27ab2f19b285f666887bf4d00b7514 Mon Sep 17 00:00:00 2001 From: Leon Romanovsky Date: Mon, 19 Mar 2018 14:20:15 +0200 Subject: [PATCH] RDMA/ucma: Fix use-after-free access in ucma_close commit ed65a4dc22083e73bac599ded6a262318cad7baf upstream. The error in ucma_create_id() left ctx in the list of contexts belong to ucma file descriptor. The attempt to close this file descriptor causes to use-after-free accesses while iterating over such list. Fixes: 75216638572f ("RDMA/cma: Export rdma cm interface to userspace") Reported-by: Signed-off-by: Leon Romanovsky Reviewed-by: Sean Hefty Signed-off-by: Jason Gunthorpe Signed-off-by: Ben Hutchings --- drivers/infiniband/core/ucma.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c index 4396ab6df02a..0a8a39ce332e 100644 --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -433,6 +433,9 @@ err1: mutex_lock(&mut); idr_remove(&ctx_idr, ctx->id); mutex_unlock(&mut); + mutex_lock(&file->mut); + list_del(&ctx->list); + mutex_unlock(&file->mut); kfree(ctx); return ret; } -- 2.39.2