3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Leon Romanovsky <leonro@xxxxxxxxxxxx> commit 002bf2282b2d7318e444dca9ffcb994afc5d5f15 upstream. Ensure that user didn't supply values too large that can cause overflow. UBSAN: Undefined behaviour in drivers/infiniband/hw/mlx5/qp.c:263:23 shift exponent -2147483648 is negative CPU: 0 PID: 292 Comm: syzkaller612609 Not tainted 4.16.0-rc1+ #131 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014 Call Trace: dump_stack+0xde/0x164 ubsan_epilogue+0xe/0x81 set_rq_size+0x7c2/0xa90 create_qp_common+0xc18/0x43c0 mlx5_ib_create_qp+0x379/0x1ca0 create_qp.isra.5+0xc94/0x2260 ib_uverbs_create_qp+0x21b/0x2a0 ib_uverbs_write+0xc2c/0x1010 vfs_write+0x1b0/0x550 SyS_write+0xc7/0x1a0 do_syscall_64+0x1aa/0x740 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x433569 RSP: 002b:00007ffc6e62f448 EFLAGS: 00000217 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000004002f8 RCX: 0000000000433569 RDX: 0000000000000070 RSI: 00000000200042c0 RDI: 0000000000000003 RBP: 00000000006d5018 R08: 00000000004002f8 R09: 00000000004002f8 R10: 00000000004002f8 R11: 0000000000000217 R12: 0000000000000000 R13: 000000000040c9f0 R14: 000000000040ca80 R15: 0000000000000006 Cc: <stable@xxxxxxxxxxxxxxx> # 3.10 Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters") Cc: syzkaller <syzkaller@xxxxxxxxxxxxxxxx> Reported-by: Noa Osherovich <noaos@xxxxxxxxxxxx> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/mlx5/qp.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/infiniband/hw/mlx5/qp.c +++ b/drivers/infiniband/hw/mlx5/qp.c @@ -174,7 +174,11 @@ static int set_rq_size(struct mlx5_ib_de } else { if (ucmd) { qp->rq.wqe_cnt = ucmd->rq_wqe_count; + if (ucmd->rq_wqe_shift > BITS_PER_BYTE * sizeof(ucmd->rq_wqe_shift)) + return -EINVAL; qp->rq.wqe_shift = ucmd->rq_wqe_shift; + if ((1 << qp->rq.wqe_shift) / sizeof(struct mlx5_wqe_data_seg) < qp->wq_sig) + return -EINVAL; qp->rq.max_gs = (1 << qp->rq.wqe_shift) / sizeof(struct mlx5_wqe_data_seg) - qp->wq_sig; qp->rq.max_post = qp->rq.wqe_cnt; } else {