From 2526d6bf27d15054bb0778b2f7bc6625fd934905 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Mon, 19 Sep 2022 09:43:27 +0300 Subject: [PATCH] crypto: cavium - prevent integer overflow loading firmware The "code_length" value comes from the firmware file. If your firmware is untrusted realistically there is probably very little you can do to protect yourself. Still we try to limit the damage as much as possible. Also Smatch marks any data read from the filesystem as untrusted and prints warnings if it not capped correctly. The "ntohl(ucode->code_length) * 2" multiplication can have an integer overflow. Fixes: 9e2c7d99941d ("crypto: cavium - Add Support for Octeon-tx CPT Engine") Signed-off-by: Dan Carpenter Signed-off-by: Herbert Xu --- drivers/crypto/cavium/cpt/cptpf_main.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/crypto/cavium/cpt/cptpf_main.c b/drivers/crypto/cavium/cpt/cptpf_main.c index 8c32d0eb8fcf..6872ac344001 100644 --- a/drivers/crypto/cavium/cpt/cptpf_main.c +++ b/drivers/crypto/cavium/cpt/cptpf_main.c @@ -253,6 +253,7 @@ static int cpt_ucode_load_fw(struct cpt_device *cpt, const u8 *fw, bool is_ae) const struct firmware *fw_entry; struct device *dev = &cpt->pdev->dev; struct ucode_header *ucode; + unsigned int code_length; struct microcode *mcode; int j, ret = 0; @@ -263,11 +264,12 @@ static int cpt_ucode_load_fw(struct cpt_device *cpt, const u8 *fw, bool is_ae) ucode = (struct ucode_header *)fw_entry->data; mcode = &cpt->mcode[cpt->next_mc_idx]; memcpy(mcode->version, (u8 *)fw_entry->data, CPT_UCODE_VERSION_SZ); - mcode->code_size = ntohl(ucode->code_length) * 2; - if (!mcode->code_size) { + code_length = ntohl(ucode->code_length); + if (code_length == 0 || code_length >= INT_MAX / 2) { ret = -EINVAL; goto fw_release; } + mcode->code_size = code_length * 2; mcode->is_ae = is_ae; mcode->core_mask = 0ULL; -- 2.34.1