As kcalloc() may fail, check its return value to avoid a NULL pointer dereference when passing the buffer to rng->read(). On allocation failure, log the error and return since test_len() returns void.

Fixes: 2be0d806e25e ("crypto: caam - add a test for the RNG") Cc: stable@vger.kernel.org Signed-off-by: Guangshuo Li lgs201920130244@gmail.com --- changelog: v3: - Fix build error: test_len() returns void; return without a value. - No functional changes beyond the allocation failure path.

v2: - Return on allocation failure to avoid possible NULL dereference. --- drivers/crypto/caam/caamrng.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/caam/caamrng.c b/drivers/crypto/caam/caamrng.c index b3d14a7f4dd1..0eb43c862516 100644 --- a/drivers/crypto/caam/caamrng.c +++ b/drivers/crypto/caam/caamrng.c @@ -181,7 +181,9 @@ static inline void test_len(struct hwrng *rng, size_t len, bool wait) struct device *dev = ctx->ctrldev;

buf = kcalloc(CAAM_RNG_MAX_FIFO_STORE_SIZE, sizeof(u8), GFP_KERNEL); - + if (!buf) { + return; + } while (len > 0) { read_len = rng->read(rng, buf, len, wait);