From 3c9fd43da473a324f6cc7a0d3db58f651a2d262c Mon Sep 17 00:00:00 2001 From: Prasad J Pandit Date: Fri, 26 Oct 2018 18:03:58 +0530 Subject: [PATCH] ppc/pnv: check size before data buffer access MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit While performing PowerNV memory r/w operations, the access length 'sz' could exceed the data[4] buffer size. Add check to avoid OOB access. Reported-by: Moguofang Signed-off-by: Prasad J Pandit Reviewed-by: Cédric Le Goater Signed-off-by: David Gibson CVE: CVE-2018-18954 Upstream-Status: Backport [https://git.qemu.org/?p=qemu.git;a=commit;h=d07945e78eb6b593cd17a4640c1fc9eb35e3245d] Signed-off-by: Dan Tran --- hw/ppc/pnv_lpc.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/hw/ppc/pnv_lpc.c b/hw/ppc/pnv_lpc.c index d7721320a2..172a915cfc 100644 --- a/hw/ppc/pnv_lpc.c +++ b/hw/ppc/pnv_lpc.c @@ -155,9 +155,15 @@ static void pnv_lpc_do_eccb(PnvLpcController *lpc, uint64_t cmd) /* XXX Check for magic bits at the top, addr size etc... */ unsigned int sz = (cmd & ECCB_CTL_SZ_MASK) >> ECCB_CTL_SZ_LSH; uint32_t opb_addr = cmd & ECCB_CTL_ADDR_MASK; - uint8_t data[4]; + uint8_t data[8]; bool success; + if (sz > sizeof(data)) { + qemu_log_mask(LOG_GUEST_ERROR, + "ECCB: invalid operation at @0x%08x size %d\n", opb_addr, sz); + return; + } + if (cmd & ECCB_CTL_READ) { success = opb_read(lpc, opb_addr, data, sz); if (success) { -- 2.22.0.vfs.1.1.57.gbaf16c8