In the Linux kernel, the following vulnerability has been resolved:
svcrdma: Address an integer overflow
Dan Carpenter reports:
Commit 78147ca8b4a9 ("svcrdma: Add a "parsed chunk list" data structure") from Jun 22, 2020 (linux-next), leads to the following Smatch static checker warning:
net/sunrpc/xprtrdma/svc_rdma_recvfrom.c:498 xdr_check_write_chunk() warn: potential user controlled sizeof overflow 'segcount * 4 * 4'
net/sunrpc/xprtrdma/svc_rdma_recvfrom.c 488 static bool xdr_check_write_chunk(struct svc_rdma_recv_ctxt *rctxt) 489 { 490 u32 segcount; 491 __be32 *p; 492 493 if (xdr_stream_decode_u32(&rctxt->rc_stream, &segcount)) ^^^^^^^^
494 return false; 495 496 /* A bogus segcount causes this buffer overflow check to fail. */ 497 p = xdr_inline_decode(&rctxt->rc_stream,--> 498 segcount * rpcrdma_segment_maxsz * sizeof(*p));
segcount is an untrusted u32. On 32bit systems anything >= SIZE_MAX / 16 will have an integer overflow and some those values will be accepted by xdr_inline_decode().
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:NI:NA:H5.5/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H