optee: ffa: Add NULL check in optee_ffa_lend_protmem

Sashiko (locally) reports a possible null dereference under memory
pressure due to the lack of validation of the allocated pointer.

Fix that by adding the missing check.

Fixes: 2b78d79cdf96 ("optee: FF-A: dynamic protected memory allocation")
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Sebastian Ene <sebastianene@google.com>
Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Reviewed-by: Sebastian Ene <sebastianene@google.com>
Signed-off-by: Jens Wiklander <jenswi@kernel.org>

diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c
index b4372fa268d032126539a59b076493cc9c2a6a62..633715b98625cdeb578fbadf514c5ac5b9558cef 100644 (file)
--- a/drivers/tee/optee/ffa_abi.c
+++ b/drivers/tee/optee/ffa_abi.c
@@ -698,6 +698,9 @@ static int optee_ffa_lend_protmem(struct optee *optee, struct tee_shm *protmem,
        int rc;
 
        mem_attr = kzalloc_objs(*mem_attr, ma_count);
+       if (!mem_attr)
+               return -ENOMEM;
+
        for (n = 0; n < ma_count; n++) {
                mem_attr[n].receiver = mem_attrs[n] & U16_MAX;
                mem_attr[n].attrs = mem_attrs[n] >> 16;