From: Bernard Metzler bmt@zurich.ibm.com
[ Upstream commit 60da2d11fcbc043304910e4d2ca82f9bab953e63 ]
A malicious user may write undefined values into memory mapped completion queue elements status or opcode. Undefined status or opcode values will result in out-of-bounds access to an array mapping siw internal representation of opcode and status to RDMA core representation when reaping CQ elements. While siw detects those undefined values, it did not correctly set completion status to a defined value, thus defeating the whole purpose of the check.
This bug leads to the following Smatch static checker warning:
drivers/infiniband/sw/siw/siw_cq.c:96 siw_reap_cqe() error: buffer overflow 'map_cqe_status' 10 <= 21
Fixes: bdf1da5df9da ("RDMA/siw: Fix immediate work request flush to completion queue") Link: https://lore.kernel.org/r/20221115170747.1263298-1-bmt@zurich.ibm.com Reported-by: Dan Carpenter error27@gmail.com Signed-off-by: Bernard Metzler bmt@zurich.ibm.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/infiniband/sw/siw/siw_cq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/infiniband/sw/siw/siw_cq.c b/drivers/infiniband/sw/siw/siw_cq.c index 26d4eb44a9d0..214714afacb7 100644 --- a/drivers/infiniband/sw/siw/siw_cq.c +++ b/drivers/infiniband/sw/siw/siw_cq.c @@ -88,9 +88,9 @@ int siw_reap_cqe(struct siw_cq *cq, struct ib_wc *wc)
if (opcode >= SIW_NUM_OPCODES) { opcode = 0; - status = IB_WC_GENERAL_ERR; + status = SIW_WC_GENERAL_ERR; } else if (status >= SIW_NUM_WC_STATUS) { - status = IB_WC_GENERAL_ERR; + status = SIW_WC_GENERAL_ERR; } wc->opcode = map_wc_opcode[opcode]; wc->status = map_cqe_status[status].ib;