From 8a682e03d7d18b3d20810ea83fcec69f8d09c909 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 12 Jun 2018 00:05:00 -0600 Subject: [PATCH] rsa: Fix missing memory leak on error in fdt_add_bignum() Thsi function can fail without freeing all its memory. Fix it. Reported-by: Coverity (CID: 131217) Signed-off-by: Simon Glass --- lib/rsa/rsa-sign.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/lib/rsa/rsa-sign.c b/lib/rsa/rsa-sign.c index d2788bf..cfe09cc 100644 --- a/lib/rsa/rsa-sign.c +++ b/lib/rsa/rsa-sign.c @@ -635,6 +635,15 @@ static int fdt_add_bignum(void *blob, int noffset, const char *prop_name, big2 = BN_new(); big32 = BN_new(); big2_32 = BN_new(); + + /* + * Note: This code assumes that all of the above succeed, or all fail. + * In practice memory allocations generally do not fail (unless the + * process is killed), so it does not seem worth handling each of these + * as a separate case. Technicaly this could leak memory on failure, + * but a) it won't happen in practice, and b) it doesn't matter as we + * will immediately exit with a failure code. + */ if (!tmp || !big2 || !big32 || !big2_32) { fprintf(stderr, "Out of memory (bignum)\n"); return -ENOMEM; @@ -667,15 +676,13 @@ static int fdt_add_bignum(void *blob, int noffset, const char *prop_name, * might fail several times */ ret = fdt_setprop(blob, noffset, prop_name, buf, size); - if (ret) - return -FDT_ERR_NOSPACE; free(buf); BN_free(tmp); BN_free(big2); BN_free(big32); BN_free(big2_32); - return ret; + return ret ? -FDT_ERR_NOSPACE : 0; } int rsa_add_verify_data(struct image_sign_info *info, void *keydest)