The previous commit 30c2235c is incomplete and cannot prevent integer overflows. For example, when key_len is 0x80000000 (INT_MAX + 1), the left-hand side of the check, (INT_MAX - key_len), which is unsigned, becomes 0xffffffff (UINT_MAX) and bypasses the check. Signed-off-by: Xi Wang <xi.wang@xxxxxxxxx> --- net/sctp/auth.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/net/sctp/auth.c b/net/sctp/auth.c index 865e68f..989e0fd 100644 --- a/net/sctp/auth.c +++ b/net/sctp/auth.c @@ -82,7 +82,7 @@ static struct sctp_auth_bytes *sctp_auth_create_key(__u32 key_len, gfp_t gfp) struct sctp_auth_bytes *key; /* Verify that we are not going to overflow INT_MAX */ - if ((INT_MAX - key_len) < sizeof(struct sctp_auth_bytes)) + if (key_len > INT_MAX - sizeof(struct sctp_auth_bytes)) return NULL; /* Allocate the shared key */ -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
