From: Pádraig Brady Date: Wed, 4 Mar 2020 12:24:49 +0000 (+0000) Subject: basenc: avoid undefined behaviour in z85 processing X-Git-Tag: v8.32~2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0ea65e29dc346e9fe39db663b2ed43d7981ed266;p=thirdparty%2Fcoreutils.git basenc: avoid undefined behaviour in z85 processing * src/basenc.c (z85_decode_ctx_init): Ensure we're working with unsigned, as otherwise ubsan triggers with: src/basenc.c:767:18: runtime error: signed integer overflow: 43 * 52200625 cannot be represented in type 'int' (z85_encode): Likewise to avoid the usban error: src/basenc.c:630:26: runtime error: left shift of 134 by 24 places cannot be represented in type 'int' --- diff --git a/src/basenc.c b/src/basenc.c index 9fb2ab9557..13c37f9048 100644 --- a/src/basenc.c +++ b/src/basenc.c @@ -627,7 +627,10 @@ z85_encode (const char *restrict in, size_t inlen, /* Got a quad, encode it */ if (i == 4) { - val = (quad[0] << 24) + (quad[1] << 16) + (quad[2] << 8) + quad[3]; + val = ((uint32_t) quad[0] << 24) + + ((uint32_t) quad[1] << 16) + + ((uint32_t) quad[2] << 8) + + quad[3]; for (int j = 4; j>=0; --j) { @@ -665,7 +668,7 @@ z85_decode_ctx_init (struct base_decode_context *ctx) # define Z85_HI_CTX_TO_32BIT_VAL(ctx) \ - ((ctx)->ctx.z85.octets[0] * 85 * 85 * 85 * 85 ) + ((uint32_t)(ctx)->ctx.z85.octets[0] * 85 * 85 * 85 * 85 ) /* 0 - 9: 0 1 2 3 4 5 6 7 8 9