NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_rbtree: fix overlap expiration walk The lazy gc on insert that should remove timed-out entries fails to release the other half of the interval, if any. Can be reproduced with tests/shell/testcases/sets/0044interval_overlap_0 in nftables.git and kmemleak enabled kernel. Second bug is the use of rbe_prev vs. prev pointer. If rbe_prev() returns NULL after at least one iteration, rbe_prev points to element that is not an end interval, hence it should not be removed. Lastly, check the genmask of the end interval if this is active in the current generation.Show less

In the Linux kernel, the following vulnerability has been resolved: mmc: rtsx_usb_sdmmc: fix return value check of mmc_add_host() mmc_add_host() may return error, if we ignore its return value, the memory that allocated in mmc_alloc_host() will be leaked and it will lead a kernel crash because of deleting not added device in the remove path. So fix this by checking the return value and calling mmc_free_host() in the error path, besides, led_classdev_unregister() and pm_runtime_disable() also need be called.Show less

In the Linux kernel, the following vulnerability has been resolved: ext4: fix null-ptr-deref in ext4_write_info I caught a null-ptr-deref bug as follows: ================================================================== KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f] CPU: 1 PID: 1589 Comm: umount Not tainted 5.10.0-02219-dirty #339 RIP: 0010:ext4_write_info+0x53/0x1b0 [...] Call Trace: dquot_writeback_dquots+0x341/0x9a0 ext4_sync_fs+0x19e/0x800 __sync_filesystem+0x83/0x100 sync_filesystem+0x89/0xf0 generic_shutdown_super+0x79/0x3e0 kill_block_super+0xa1/0x110 deactivate_locked_super+0xac/0x130 deactivate_super+0xb6/0xd0 cleanup_mnt+0x289/0x400 __cleanup_mnt+0x16/0x20 task_work_run+0x11c/0x1c0 exit_to_user_mode_prepare+0x203/0x210 syscall_exit_to_user_mode+0x5b/0x3a0 do_syscall_64+0x59/0x70 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ================================================================== Above issue may happen as follows: ------------------------------------- exit_to_user_mode_prepare task_work_run __cleanup_mnt cleanup_mnt deactivate_super deactivate_locked_super kill_block_super generic_shutdown_super shrink_dcache_for_umount dentry = sb->s_root sb->s_root = NULL <--- Here set NULL sync_filesystem __sync_filesystem sb->s_op->sync_fs > ext4_sync_fs dquot_writeback_dquots sb->dq_op->write_info > ext4_write_info ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2) d_inode(sb->s_root) s_root->d_inode <--- Null pointer dereference To solve this problem, we use ext4_journal_start_sb directly to avoid s_root being used.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: Add a null ptr check for dpu_encoder_needs_modeset The drm_atomic_get_new_connector_state() can return NULL if the connector is not part of the atomic state. Add a check to prevent a NULL pointer dereference. This follows the same pattern used in dpu_encoder_update_topology() within the same file, which checks for NULL before using conn_state. Patchwork: https://patchwork.freedesktop.org/patch/665188/Show less

In the Linux kernel, the following vulnerability has been resolved: ice: fix NULL pointer dereference in ice_unplug_aux_dev() on reset Issuing a reset when the driver is loaded without RDMA support, will results in a crash as it attempts to remove RDMA's non-existent auxbus device: echo 1 > /sys/class/net/<if>/device/reset BUG: kernel NULL pointer dereference, address: 0000000000000008 ... RIP: 0010:ice_unplug_aux_dev+0x29/0x70 [ice] ... Call Trace: <TASK> ice_prepare_for_reset+0x77/0x260 [ice] pci_dev_save_and_disable+0x2c/0x70 pci_reset_function+0x88/0x130 reset_store+0x5a/0xa0 kernfs_fop_write_iter+0x15e/0x210 vfs_write+0x273/0x520 ksys_write+0x6b/0xe0 do_syscall_64+0x79/0x3b0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ice_unplug_aux_dev() checks pf->cdev_info->adev for NULL pointer, but pf->cdev_info will also be NULL, leading to the deref in the trace above. Introduce a flag to be set when the creation of the auxbus device is successful, to avoid multiple NULL pointer checks in ice_unplug_aux_dev().Show less

In the Linux kernel, the following vulnerability has been resolved: drm/xe/vm: Clear the scratch_pt pointer on error Avoid triggering a dereference of an error pointer on cleanup in xe_vm_free_scratch() by clearing any scratch_pt error pointer. (cherry picked from commit 358ee50ab565f3c8ea32480e9d03127a81ba32f8)Show less

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: Add error handling for old state CRTC in atomic_disable Introduce error handling to address an issue where, after a hotplug event, the cursor continues to update. This situation can lead to a kernel panic due to accessing the NULL `old_state->crtc`. E,g. Unable to handle kernel NULL pointer dereference at virtual address Call trace: mtk_crtc_plane_disable+0x24/0x140 mtk_plane_atomic_update+0x8c/0xa8 drm_atomic_helper_commit_planes+0x114/0x2c8 drm_atomic_helper_commit_tail_rpm+0x4c/0x158 commit_tail+0xa0/0x168 drm_atomic_helper_commit+0x110/0x120 drm_atomic_commit+0x8c/0xe0 drm_atomic_helper_update_plane+0xd4/0x128 __setplane_atomic+0xcc/0x110 drm_mode_cursor_common+0x250/0x440 drm_mode_cursor_ioctl+0x44/0x70 drm_ioctl+0x264/0x5d8 __arm64_sys_ioctl+0xd8/0x510 invoke_syscall+0x6c/0xe0 do_el0_svc+0x68/0xe8 el0_svc+0x34/0x60 el0t_64_sync_handler+0x1c/0xf8 el0t_64_sync+0x180/0x188 Adding NULL pointer checks to ensure stability by preventing operations on an invalid CRTC state.Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: iwl4965: Add missing check for create_singlethread_workqueue() Add the check for the return value of the create_singlethread_workqueue() in order to avoid NULL pointer dereference.Show less

In the Linux kernel, the following vulnerability has been resolved: sctp: check send stream number after wait_for_sndbuf This patch fixes a corner case where the asoc out stream count may change after wait_for_sndbuf. When the main thread in the client starts a connection, if its out stream count is set to N while the in stream count in the server is set to N - 2, another thread in the client keeps sending the msgs with stream number N - 1, and waits for sndbuf before processing INIT_ACK. However, after processing INIT_ACK, the out stream count in the client is shrunk to N - 2, the same to the in stream count in the server. The crash occurs when the thread waiting for sndbuf is awake and sends the msg in a non-existing stream(N - 1), the call trace is as below: KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] Call Trace: <TASK> sctp_cmd_send_msg net/sctp/sm_sideeffect.c:1114 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1777 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x197d/0x5310 net/sctp/sm_sideeffect.c:1170 sctp_primitive_SEND+0x9f/0xc0 net/sctp/primitive.c:163 sctp_sendmsg_to_asoc+0x10eb/0x1a30 net/sctp/socket.c:1868 sctp_sendmsg+0x8d4/0x1d90 net/sctp/socket.c:2026 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825 sock_sendmsg_nosec net/socket.c:722 [inline] sock_sendmsg+0xde/0x190 net/socket.c:745 The fix is to add an unlikely check for the send stream number after the thread wakes up from the wait_for_sndbuf.Show less

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Fix null-ptr-deref on inode->i_op in ntfs_lookup() Syzbot reported a null-ptr-deref bug: ntfs3: loop0: Different NTFS' sector size (1024) and media sector size (512) ntfs3: loop0: Mark volume as dirty due to NTFS errors general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] RIP: 0010:d_flags_for_inode fs/dcache.c:1980 [inline] RIP: 0010:__d_add+0x5ce/0x800 fs/dcache.c:2796 Call Trace: <TASK> d_splice_alias+0x122/0x3b0 fs/dcache.c:3191 lookup_open fs/namei.c:3391 [inline] open_last_lookups fs/namei.c:3481 [inline] path_openat+0x10e6/0x2df0 fs/namei.c:3688 do_filp_open+0x264/0x4f0 fs/namei.c:3718 do_sys_openat2+0x124/0x4e0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_open fs/open.c:1334 [inline] __se_sys_open fs/open.c:1330 [inline] __x64_sys_open+0x221/0x270 fs/open.c:1330 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd If the MFT record of ntfs inode is not a base record, inode->i_op can be NULL. And a null-ptr-deref may happen: ntfs_lookup() dir_search_u() # inode->i_op is set to NULL d_splice_alias() __d_add() d_flags_for_inode() # inode->i_op->get_link null-ptr-deref Fix this by adding a Check on inode->i_op before calling the d_splice_alias() function.Show less

In the Linux kernel, the following vulnerability has been resolved: blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch_none After grabbing q->sysfs_lock, q->elevator may become NULL because of elevator switch. Fix the NULL dereference on q->elevator by checking it with lock.Show less

In the Linux kernel, the following vulnerability has been resolved: media: bdisp: Add missing check for create_workqueue Add the check for the return value of the create_workqueue in order to avoid NULL pointer dereference.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: check for null return of devm_kzalloc() in dpu_writeback_init() Because of the possilble failure of devm_kzalloc(), dpu_wb_conn might be NULL and will cause null pointer dereference later. Therefore, it might be better to check it and directly return -ENOMEM. Patchwork: https://patchwork.freedesktop.org/patch/512277/ [DB: fixed typo in commit message]Show less

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Remove unused nvme_ls_waitq wait queue System crash when qla2x00_start_sp(sp) returns error code EGAIN and wake_up gets called for uninitialized wait queue sp->nvme_ls_waitq. qla2xxx [0000:37:00.1]-2121:5: Returning existing qpair of ffff8ae2c0513400 for idx=0 qla2xxx [0000:37:00.1]-700e:5: qla2x00_start_sp failed = 11 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 PGD 0 P4D 0 Oops: 0000 [#1] SMP NOPTI Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 09/03/2021 Workqueue: nvme-wq nvme_fc_connect_ctrl_work [nvme_fc] RIP: 0010:__wake_up_common+0x4c/0x190 RSP: 0018:ffff95f3e0cb7cd0 EFLAGS: 00010086 RAX: 0000000000000000 RBX: ffff8b08d3b26328 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8b08d3b26320 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffffffffffe8 R10: 0000000000000000 R11: ffff95f3e0cb7a60 R12: ffff95f3e0cb7d20 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8b2fdf6c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000002f1e410002 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: __wake_up_common_lock+0x7c/0xc0 qla_nvme_ls_req+0x355/0x4c0 [qla2xxx] ? __nvme_fc_send_ls_req+0x260/0x380 [nvme_fc] ? nvme_fc_send_ls_req.constprop.42+0x1a/0x45 [nvme_fc] ? nvme_fc_connect_ctrl_work.cold.63+0x1e3/0xa7d [nvme_fc] Remove unused nvme_ls_waitq wait queue. nvme_ls_waitq logic was removed previously in the commits tagged Fixed: below.Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: iwl3945: Add missing check for create_singlethread_workqueue Add the check for the return value of the create_singlethread_workqueue in order to avoid NULL pointer dereference.Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: hda: fix a possible null-pointer dereference due to data race in snd_hdac_regmap_sync() The variable codec->regmap is often protected by the lock codec->regmap_lock when is accessed. However, it is accessed without holding the lock when is accessed in snd_hdac_regmap_sync(): if (codec->regmap) In my opinion, this may be a harmful race, because if codec->regmap is set to NULL right after the condition is checked, a null-pointer dereference can occur in the called function regcache_sync(): map->lock(map->lock_arg); --> Line 360 in drivers/base/regmap/regcache.c To fix this possible null-pointer dereference caused by data race, the mutex_lock coverage is extended to protect the if statement as well as the function call to regcache_sync(). [ Note: the lack of the regmap_lock itself is harmless for the current codec driver implementations, as snd_hdac_regmap_sync() is only for PM runtime resume that is prohibited during the codec probe. But the change makes the whole code more consistent, so it's merged as is -- tiwai ]Show less

In the Linux kernel, the following vulnerability has been resolved: Drivers: vmbus: Check for channel allocation before looking up relids relid2channel() assumes vmbus channel array to be allocated when called. However, in cases such as kdump/kexec, not all relids will be reset by the host. When the second kernel boots and if the guest receives a vmbus interrupt during vmbus driver initialization before vmbus_connect() is called, before it finishes, or if it fails, the vmbus interrupt service routine is called which in turn calls relid2channel() and can cause a null pointer dereference. Print a warning and error out in relid2channel() for a channel id that's invalid in the second kernel.Show less

A null pointer dereference vulnerability was discovered in SumatraPDF 3.5.2 during the processing of a crafted .djvu file. When the file is opened, the application crashes inside libmupdf.dll, specifically in the DataPool::has_data() function.Show less

In the Linux kernel, the following vulnerability has been resolved: ovl: fix null pointer dereference in ovl_permission() Following process: P1 P2 path_lookupat link_path_walk inode_permission ovl_permission ovl_i_path_real(inode, &realpath) path->dentry = ovl_i_dentry_upper(inode) drop_cache __dentry_kill(ovl_dentry) iput(ovl_inode) ovl_destroy_inode(ovl_inode) dput(oi->__upperdentry) dentry_kill(upperdentry) dentry_unlink_inode upperdentry->d_inode = NULL realinode = d_inode(realpath.dentry) // return NULL inode_permission(realinode) inode->i_sb // NULL pointer dereference , will trigger an null pointer dereference at realinode: [ 335.664979] BUG: kernel NULL pointer dereference, address: 0000000000000002 [ 335.668032] CPU: 0 PID: 2592 Comm: ls Not tainted 6.3.0 [ 335.669956] RIP: 0010:inode_permission+0x33/0x2c0 [ 335.678939] Call Trace: [ 335.679165] <TASK> [ 335.679371] ovl_permission+0xde/0x320 [ 335.679723] inode_permission+0x15e/0x2c0 [ 335.680090] link_path_walk+0x115/0x550 [ 335.680771] path_lookupat.isra.0+0xb2/0x200 [ 335.681170] filename_lookup+0xda/0x240 [ 335.681922] vfs_statx+0xa6/0x1f0 [ 335.682233] vfs_fstatat+0x7b/0xb0 Fetch a reproducer in [Link]. Use the helper ovl_i_path_realinode() to get realinode and then do non-nullptr checking.Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: pcie: fix NULL pointer dereference in iwl_pcie_irq_rx_msix_handler() rxq can be NULL only when trans_pcie->rxq is NULL and entry->entry is zero. For the case when entry->entry is not equal to 0, rxq won't be NULL even if trans_pcie->rxq is NULL. Modify checker to check for trans_pcie->rxq.Show less