On Fri, Aug 31, 2018 at 07:15:56AM -0700, Steve Wise wrote: > Once the qp has been flushed, it cannot be flushed again. The user > qp flush logic wasn't enforcing it however. The bug can cause > touch-after-free crashes like: > > Unable to handle kernel paging request for data at address 0x000001ec > Faulting instruction address: 0xc008000016069100 > Oops: Kernel access of bad area, sig: 11 [#1] > ... > NIP [c008000016069100] flush_qp+0x80/0x480 [iw_cxgb4] > LR [c00800001606cd6c] c4iw_modify_qp+0x71c/0x11d0 [iw_cxgb4] > Call Trace: > [c00800001606cd6c] c4iw_modify_qp+0x71c/0x11d0 [iw_cxgb4] > [c00800001606e868] c4iw_ib_modify_qp+0x118/0x200 [iw_cxgb4] > [c0080000119eae80] ib_security_modify_qp+0xd0/0x3d0 [ib_core] > [c0080000119c4e24] ib_modify_qp+0xc4/0x2c0 [ib_core] > [c008000011df0284] iwcm_modify_qp_err+0x44/0x70 [iw_cm] > [c008000011df0fec] destroy_cm_id+0xcc/0x370 [iw_cm] > [c008000011ed4358] rdma_destroy_id+0x3c8/0x520 [rdma_cm] > [c0080000134b0540] ucma_close+0x90/0x1b0 [rdma_ucm] > [c000000000444da4] __fput+0xe4/0x2f0 > > So fix flush_qp() to only flush the wq once. > > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx> > --- > drivers/infiniband/hw/cxgb4/qp.c | 6 ++++++ > 1 file changed, 6 insertions(+) Applied to for-rc, thanks Jason
