On Mon, Mar 03, 2025 at 01:08:29PM +0300, Dan Carpenter wrote: > Real bugs where we dereference a pointer and then check for NULL don't > last long in the kernel. Most of the stuff Markus is sending is false > positives like this. Maybe I was too optimistic. Here are the Smatch warnings from the Friday's linux-next. Common false positives are that the pointer can sometimes be NULL but there are other ways to determine without checking explicitly. For example, maybe the caller passes a flag which means it's non-NULL. regards, dan carpenter arch/arm64/kvm/../../../virt/kvm/kvm_main.c:1639 kvm_prepare_memory_region() warn: variable dereferenced before check 'new' (see line 1622) arch/x86/kernel/fpu/xstate.c:1567 fpstate_realloc() warn: variable dereferenced before check 'curfps' (see line 1546) arch/x86/kvm/../../../virt/kvm/kvm_main.c:1639 kvm_prepare_memory_region() warn: variable dereferenced before check 'new' (see line 1622) drivers/base/dd.c:696 really_probe() warn: variable dereferenced before check 'dev->bus' (see line 640) drivers/base/dd.c:720 really_probe() warn: variable dereferenced before check 'dev->bus' (see line 640) drivers/block/drbd/drbd_worker.c:588 make_resync_request() warn: variable dereferenced before check 'peer_device' (see line 587) drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:12341 parse_edid_displayid_vrr() warn: variable dereferenced before check 'edid_ext' (see line 12337) drivers/gpu/drm/amd/amdgpu/../display/dc/clk_mgr/dcn21/rn_clk_mgr.c:775 rn_clk_mgr_construct() warn: variable dereferenced before check 'ctx->dc_bios->integrated_info' (see line 743) drivers/gpu/drm/amd/amdgpu/../display/dc/clk_mgr/dcn301/vg_clk_mgr.c:734 vg_clk_mgr_construct() warn: variable dereferenced before check 'ctx->dc_bios->integrated_info' (see line 720) drivers/gpu/drm/amd/amdgpu/../display/dc/clk_mgr/dcn314/dcn314_clk_mgr.c:899 dcn314_clk_mgr_construct() warn: variable dereferenced before check 'ctx->dc_bios->integrated_info' (see line 838) drivers/gpu/drm/amd/amdgpu/../display/dc/clk_mgr/dcn315/dcn315_clk_mgr.c:715 dcn315_clk_mgr_construct() warn: variable dereferenced before check 'ctx->dc_bios->integrated_info' (see line 654) drivers/gpu/drm/amd/amdgpu/../display/dc/clk_mgr/dcn316/dcn316_clk_mgr.c:655 dcn316_clk_mgr_construct() warn: variable dereferenced before check 'ctx->dc_bios->integrated_info' (see line 634) drivers/gpu/drm/amd/amdgpu/../display/dc/clk_mgr/dcn31/dcn31_clk_mgr.c:789 dcn31_clk_mgr_construct() warn: variable dereferenced before check 'ctx->dc_bios->integrated_info' (see line 728) drivers/gpu/drm/amd/amdgpu/../display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c:1380 dcn35_clk_mgr_construct() warn: variable dereferenced before check 'ctx->dc_bios->integrated_info' (see line 1307) drivers/gpu/drm/i915/gem/i915_gem_shmem.c:174 shmem_sg_alloc_table() warn: variable dereferenced before check 'sg' (see line 163) drivers/gpu/drm/i915/gt/gen6_ppgtt.c:274 gen6_ppgtt_cleanup() warn: variable dereferenced before check 'ppgtt->base.pd' (see line 271) drivers/gpu/drm/i915/gt/intel_execlists_submission.c:3649 rcu_virtual_context_destroy() warn: variable dereferenced before check 've->base.sched_engine' (see line 3623) drivers/gpu/drm/nouveau/nouveau_dp.c:494 nouveau_dp_irq() warn: variable dereferenced before check 'outp' (see line 489) drivers/hid/hid-debug.c:3727 hid_debug_events_read() warn: variable dereferenced before check 'list->hdev' (see line 3713) drivers/net/ethernet/amd/pcnet32.c:1923 pcnet32_probe1() warn: variable dereferenced before check 'pdev' (see line 1843) drivers/net/ethernet/apm/xgene/xgene_enet_main.c:267 xgene_enet_tx_completion() warn: variable dereferenced before check 'skb' (see line 243) drivers/net/ethernet/natsemi/ns83820.c:884 rx_irq() warn: variable dereferenced before check 'skb' (see line 883) drivers/net/ethernet/pensando/ionic/ionic_txrx.c:205 ionic_rx_build_skb() warn: variable dereferenced before check 'buf_info->page' (see line 188) drivers/net/wireless/intel/iwlwifi/dvm/mac80211.c:1236 iwl_setup_interface() warn: variable dereferenced before check 'priv->lib->bt_params' (see line 1229) drivers/net/wireless/intel/iwlwifi/dvm/main.c:1114 iwl_init_drv() warn: variable dereferenced before check 'priv->lib->bt_params' (see line 1109) drivers/net/wireless/mediatek/mt76/mt76_connac_mac.c:307 mt76_connac2_mac_tx_rate_val() warn: variable dereferenced before check 'conf' (see line 300) drivers/net/wireless/mediatek/mt76/mt7925/mac.c:851 mt7925_tx_check_aggr() warn: variable dereferenced before check 'sta' (see line 847) drivers/nvme/host/ioctl.c:173 nvme_map_user_request() warn: variable dereferenced before check 'bio' (see line 162) drivers/platform/mellanox/mlxreg-lc.c:903 mlxreg_lc_probe() warn: variable dereferenced before check 'data->notifier' (see line 828) drivers/scsi/aacraid/commsup.c:2344 aac_command_thread() warn: variable dereferenced before check 'dev->queues' (see line 2332) drivers/scsi/aic7xxx/aic79xx_osm.c:1837 ahd_done() warn: variable dereferenced before check 'cmd' (see line 1793) drivers/scsi/csiostor/csio_mb.c:932 csio_fcoe_vnp_alloc_init_mb() warn: variable dereferenced before check 'vnport_wwnn' (see line 929) drivers/scsi/ips.c:2560 ips_next() warn: variable dereferenced before check 'scb->scsi_cmd' (see line 2554) drivers/scsi/ips.c:2568 ips_next() warn: variable dereferenced before check 'scb->scsi_cmd' (see line 2554) drivers/scsi/ips.c:2593 ips_next() warn: variable dereferenced before check 'scb->scsi_cmd' (see line 2554) drivers/scsi/libsas/sas_scsi_host.c:119 sas_scsi_task_done() warn: variable dereferenced before check 'sc' (see line 110) drivers/scsi/lpfc/lpfc_bsg.c:1332 lpfc_bsg_hba_get_event() warn: variable dereferenced before check 'evt_dat' (see line 1299) drivers/slimbus/qcom-ngd-ctrl.c:884 qcom_slim_ngd_xfer_msg() warn: variable dereferenced before check 'txn->msg' (see line 808) drivers/spi/spi-offload.c:186 spi_offload_trigger_get() warn: variable dereferenced before check 'trigger->ops' (see line 176) drivers/staging/media/atomisp/pci/isp/kernels/output/output_1.0/ia_css_output.host.c:58 ia_css_output_config() warn: variable dereferenced before check 'from->info' (see line 53) drivers/usb/gadget/udc/tegra-xudc.c:2681 tegra_xudc_handle_transfer_completion() warn: variable dereferenced before check 'ep->desc' (see line 2679) drivers/usb/musb/musb_core.c:964 musb_handle_intr_disconnect() warn: variable dereferenced before check 'musb->hcd' (see line 963) fs/bcachefs/journal.c:1187 __bch2_set_nr_journal_buckets() warn: variable dereferenced before check 'c' (see line 1184) fs/efs/inode.c:299 efs_map_block() warn: variable dereferenced before check 'bh' (see line 292) fs/efs/inode.c:304 efs_map_block() warn: variable dereferenced before check 'bh' (see line 292) fs/efs/inode.c:309 efs_map_block() warn: variable dereferenced before check 'bh' (see line 292) fs/nfs/write.c:808 nfs_inode_remove_request() warn: variable dereferenced before check 'folio' (see line 805) fs/ocfs2/dlm/dlmrecovery.c:1590 dlm_mig_lockres_worker() warn: variable dereferenced before check 'res' (see line 1563) fs/ocfs2/move_extents.c:322 ocfs2_defrag_extent() warn: variable dereferenced before check 'context->data_ac' (see line 279) fs/ocfs2/namei.c:1455 ocfs2_rename() warn: variable dereferenced before check 'newfe_bh' (see line 1452) fs/ocfs2/namei.c:1637 ocfs2_rename() warn: variable dereferenced before check 'old_dir_bh' (see line 1618) fs/smb/client/file.c:3085 cifs_oplock_break() warn: variable dereferenced before check 'inode' (see line 3056) lib/reed_solomon/decode_rs.c:315 decode_rs16() warn: variable dereferenced before check 'par' (see line 81) net/core/failover.c:85 failover_slave_register() warn: variable dereferenced before check 'fops' (see line 66) net/mpls/mpls_iptunnel.c:156 mpls_xmit() warn: variable dereferenced before check 'out_dev' (see line 56)
