From: Kees Cook <keescook@xxxxxxxxxxxx> [ Upstream commit e329e71013c9b5a4535b099208493c7826ee4a64 ] While running under CONFIG_FORTIFY_SOURCE=y, syzkaller reported: memcpy: detected field-spanning write (size 129) of single field "target->sensf_res" at net/nfc/nci/ntf.c:260 (size 18) This appears to be a legitimate lack of bounds checking in nci_add_new_protocol(). Add the missing checks. Reported-by: syzbot+210e196cef4711b65139@xxxxxxxxxxxxxxxxxxxxxxxxx Link: https://lore.kernel.org/lkml/0000000000001c590f05ee7b3ff4@xxxxxxxxxx Fixes: 019c4fbaa790 ("NFC: Add NCI multiple targets support") Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> Link: https://lore.kernel.org/r/20221202214410.never.693-kees@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/nfc/nci/ntf.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/nfc/nci/ntf.c b/net/nfc/nci/ntf.c index 282c51051dcc..994a0a1efb58 100644 --- a/net/nfc/nci/ntf.c +++ b/net/nfc/nci/ntf.c @@ -240,6 +240,8 @@ static int nci_add_new_protocol(struct nci_dev *ndev, target->sens_res = nfca_poll->sens_res; target->sel_res = nfca_poll->sel_res; target->nfcid1_len = nfca_poll->nfcid1_len; + if (target->nfcid1_len > ARRAY_SIZE(target->nfcid1)) + return -EPROTO; if (target->nfcid1_len > 0) { memcpy(target->nfcid1, nfca_poll->nfcid1, target->nfcid1_len); @@ -248,6 +250,8 @@ static int nci_add_new_protocol(struct nci_dev *ndev, nfcb_poll = (struct rf_tech_specific_params_nfcb_poll *)params; target->sensb_res_len = nfcb_poll->sensb_res_len; + if (target->sensb_res_len > ARRAY_SIZE(target->sensb_res)) + return -EPROTO; if (target->sensb_res_len > 0) { memcpy(target->sensb_res, nfcb_poll->sensb_res, target->sensb_res_len); @@ -256,6 +260,8 @@ static int nci_add_new_protocol(struct nci_dev *ndev, nfcf_poll = (struct rf_tech_specific_params_nfcf_poll *)params; target->sensf_res_len = nfcf_poll->sensf_res_len; + if (target->sensf_res_len > ARRAY_SIZE(target->sensf_res)) + return -EPROTO; if (target->sensf_res_len > 0) { memcpy(target->sensf_res, nfcf_poll->sensf_res, target->sensf_res_len); -- 2.35.1
