4.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Leon Romanovsky <[email protected]> [ Upstream commit a5cc9831af05e658543593abaee45a29d061bac4 ] Number of specs is provided by user and in valid case can be equal to zero. Such argument causes to call to kcalloc() with zero-length request and in return the ZERO_SIZE_PTR is assigned. This pointer is different from NULL and makes various if (..) checks to success. Fixes: b6ba4a9aa59f ("IB/uverbs: Add support for flow counters") Signed-off-by: Leon Romanovsky <[email protected]> Signed-off-by: Jason Gunthorpe <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/infiniband/core/uverbs_cmd.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -2812,6 +2812,9 @@ static struct ib_uflow_resources *flow_r if (!resources) goto err_res; + if (!num_specs) + goto out; + resources->counters = kcalloc(num_specs, sizeof(*resources->counters), GFP_KERNEL); @@ -2824,8 +2827,8 @@ static struct ib_uflow_resources *flow_r if (!resources->collection) goto err_collection; +out: resources->max = num_specs; - return resources; err_collection:
