From c71b5fcbd3ab1476a40e28a3db68dc28d3be512e Mon Sep 17 00:00:00 2001 From: Michal Mielewczyk Date: Tue, 16 Jun 2020 04:01:54 -0400 Subject: [PATCH] Access attach command conditionaly If cache is restored after upgrade, NULL is passed instead of `struct kcas_start_cache`. This leads to null pointer dereference. To prevent null pointer dereference, `struct kcas_start_cache` is tested before each use Signed-off-by: Michal Mielewczyk --- modules/cas_cache/layer_cache_management.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/modules/cas_cache/layer_cache_management.c b/modules/cas_cache/layer_cache_management.c index e3d31fc..7ee0bd4 100644 --- a/modules/cas_cache/layer_cache_management.c +++ b/modules/cas_cache/layer_cache_management.c @@ -1836,7 +1836,7 @@ static void init_instance_complete(struct _cache_mngt_attach_context *ctx, /* Set other back information */ name = block_dev_get_elevator_name( casdsk_disk_get_queue(bd_cache_obj->dsk)); - if (name) + if (name && ctx->cmd) strlcpy(ctx->cmd->cache_elevator, name, MAX_ELEVATOR_NAME); } @@ -1893,7 +1893,7 @@ static void _cache_mngt_start_complete(ocf_cache_t cache, void *priv, int error) int caller_status = _cache_mngt_async_callee_peek_result(&ctx->async); if (caller_status || error) { - if (error == -OCF_ERR_NO_FREE_RAM) { + if (error == -OCF_ERR_NO_FREE_RAM && ctx->cmd) { ocf_mngt_get_ram_needed(cache, ctx->device_cfg, &ctx->cmd->min_free_ram); } else if (caller_status == -KCAS_ERR_WAITING_INTERRUPTED) {