From 1901b91f99821955eac2bd48fe25ee983385dc00 Mon Sep 17 00:00:00 2001 From: Jack Morgenstein Date: Thu, 7 May 2020 10:10:12 +0300 Subject: [PATCH] IB/core: Fix potential NULL pointer dereference in pkey cache The IB core pkey cache is populated by procedure ib_cache_update(). Initially, the pkey cache pointer is NULL. ib_cache_update allocates a buffer and populates it with the device's pkeys, via repeated calls to procedure ib_query_pkey(). If there is a failure in populating the pkey buffer via ib_query_pkey(), ib_cache_update does not replace the old pkey buffer cache with the updated one -- it leaves the old cache as is. Since initially the pkey buffer cache is NULL, when calling ib_cache_update the first time, a failure in ib_query_pkey() will cause the pkey buffer cache pointer to remain NULL. In this situation, any calls subsequent to ib_get_cached_pkey(), ib_find_cached_pkey(), or ib_find_cached_pkey_exact() will try to dereference the NULL pkey cache pointer, causing a kernel panic. Fix this by checking the ib_cache_update() return value. Fixes: 8faea9fd4a39 ("RDMA/cache: Move the cache per-port data into the main ib_port_data") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Link: https://lore.kernel.org/r/20200507071012.100594-1-leon@kernel.org Signed-off-by: Jack Morgenstein Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe --- drivers/infiniband/core/cache.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/core/cache.c b/drivers/infiniband/core/cache.c index 717b798cddad4..a670209bbce60 100644 --- a/drivers/infiniband/core/cache.c +++ b/drivers/infiniband/core/cache.c @@ -1553,8 +1553,11 @@ int ib_cache_setup_one(struct ib_device *device) if (err) return err; - rdma_for_each_port (device, p) - ib_cache_update(device, p, true); + rdma_for_each_port (device, p) { + err = ib_cache_update(device, p, true); + if (err) + return err; + } return 0; }