In the Linux kernel, the following vulnerability has been resolved: net: dsa: improve shutdown sequence Alexander Sverdlin presents 2 problems during shutdown with the lan9303 driver. One is specific to lan9303 and the other just happens to reproduce there. The first problem is that lan9303 is unique among DSA drivers in that it calls dev_get_drvdata() at "arbitrary runtime" (not probe, not shutdown, not remove): phy_state_machine() -> ... -> dsa_user_phy_read() -> ds->ops->phy_read() -> lan9303_phy_read() -> chip->ops->phy_read() -> lan9303_mdio_phy_read() -> dev_get_drvdata() But we never stop the phy_state_machine(), so it may continue to run after dsa_switch_shutdown(). Our common pattern in all DSA drivers is to set drvdata to NULL to suppress the remove() method that may come afterwards. But in this case it will result in an NPD. The second problem is that the way in which we set dp->conduit->dsa_ptr = NULL; is concurrent with receive packet processing. dsa_switch_rcv() checks once whether dev->dsa_ptr is NULL, but afterwards, rather than continuing to use that non-NULL value, dev->dsa_ptr is dereferenced again and again without NULL checks: dsa_conduit_find_user() and many other places. In between dereferences, there is no locking to ensure that what was valid once continues to be valid. Both problems have the common aspect that closing the conduit interface solves them. In the first case, dev_close(conduit) triggers the NETDEV_GOING_DOWN event in dsa_user_netdevice_event() which closes user ports as well. dsa_port_disable_rt() calls phylink_stop(), which synchronously stops the phylink state machine, and ds->ops->phy_read() will thus no longer call into the driver after this point. In the second case, dev_close(conduit) should do this, as per Documentation/networking/driver.rst: | Quiescence | ---------- | | After the ndo_stop routine has been called, the hardware must | not receive or transmit any data. All in flight packets must | be aborted. If necessary, poll or wait for completion of | any reset commands. So it should be sufficient to ensure that later, when we zeroize conduit->dsa_ptr, there will be no concurrent dsa_switch_rcv() call on this conduit. The addition of the netif_device_detach() function is to ensure that ioctls, rtnetlinks and ethtool requests on the user ports no longer propagate down to the driver - we're no longer prepared to handle them. The race condition actually did not exist when commit 0650bf52b31f ("net: dsa: be compatible with masters which unregister on shutdown") first introduced dsa_switch_shutdown(). It was created later, when we stopped unregistering the user interfaces from a bad spot, and we just replaced that sequence with a racy zeroization of conduit->dsa_ptr (one which doesn't ensure that the interfaces aren't up).

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: lantiq_etop: fix memory disclosure When applying padding, the buffer is not zeroed, which results in memory disclosure. The mentioned data is observed on the wire. This patch uses skb_put_padto() to pad Ethernet frames properly. The mentioned function zeroes the expanded buffer. In case the packet cannot be padded it is silently dropped. Statistics are also not incremented. This driver does not support statistics in the old 32-bit format or the new 64-bit format. These will be added in the future. In its current form, the patch should be easily backported to stable versions. Ethernet MACs on Amazon-SE and Danube cannot do padding of the packets in hardware, so software padding must be applied.

In the Linux kernel, the following vulnerability has been resolved: cifs: Fix buffer overflow when parsing NFS reparse points ReparseDataLength is sum of the InodeType size and DataBuffer size. So to get DataBuffer size it is needed to subtract InodeType's size from ReparseDataLength. Function cifs_strndup_from_utf16() is currentlly accessing buf->DataBuffer at position after the end of the buffer because it does not subtract InodeType size from the length. Fix this problem and correctly subtract variable len. Member InodeType is present only when reparse buffer is large enough. Check for ReparseDataLength before accessing InodeType to prevent another invalid memory access. Major and minor rdev values are present also only when reparse buffer is large enough. Check for reparse buffer size before calling reparse_mkdev().

In the Linux kernel, the following vulnerability has been resolved: tipc: guard against string buffer overrun Smatch reports that copying media_name and if_name to name_parts may overwrite the destination. .../bearer.c:166 bearer_name_validate() error: strcpy() 'media_name' too large for 'name_parts->media_name' (32 vs 16) .../bearer.c:167 bearer_name_validate() error: strcpy() 'if_name' too large for 'name_parts->if_name' (1010102 vs 16) This does seem to be the case so guard against this possibility by using strscpy() and failing if truncation occurs. Introduced by commit b97bf3fd8f6a ("[TIPC] Initial merge") Compile tested only.

In the Linux kernel, the following vulnerability has been resolved: block: fix integer overflow in BLKSECDISCARD I independently rediscovered commit 22d24a544b0d49bbcbd61c8c0eaf77d3c9297155 block: fix overflow in blk_ioctl_discard() but for secure erase. Same problem: uint64_t r[2] = {512, 18446744073709551104ULL}; ioctl(fd, BLKSECDISCARD, r); will enter near infinite loop inside blkdev_issue_secure_erase(): a.out: attempt to access beyond end of device loop0: rw=5, sector=3399043073, nr_sectors = 1024 limit=2048 bio_check_eod: 3286214 callbacks suppressed

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix potential lockup if qi_submit_sync called with 0 count If qi_submit_sync() is invoked with 0 invalidation descriptors (for instance, for DMA draining purposes), we can run into a bug where a submitting thread fails to detect the completion of invalidation_wait. Subsequently, this led to a soft lockup. Currently, there is no impact by this bug on the existing users because no callers are submitting invalidations with 0 descriptors. This fix will enable future users (such as DMA drain) calling qi_submit_sync() with 0 count. Suppose thread T1 invokes qi_submit_sync() with non-zero descriptors, while concurrently, thread T2 calls qi_submit_sync() with zero descriptors. Both threads then enter a while loop, waiting for their respective descriptors to complete. T1 detects its completion (i.e., T1's invalidation_wait status changes to QI_DONE by HW) and proceeds to call reclaim_free_desc() to reclaim all descriptors, potentially including adjacent ones of other threads that are also marked as QI_DONE. During this time, while T2 is waiting to acquire the qi->q_lock, the IOMMU hardware may complete the invalidation for T2, setting its status to QI_DONE. However, if T1's execution of reclaim_free_desc() frees T2's invalidation_wait descriptor and changes its status to QI_FREE, T2 will not observe the QI_DONE status for its invalidation_wait and will indefinitely remain stuck. This soft lockup does not occur when only non-zero descriptors are submitted.In such cases, invalidation descriptors are interspersed among wait descriptors with the status QI_IN_USE, acting as barriers. These barriers prevent the reclaim code from mistakenly freeing descriptors belonging to other submitters. Considered the following example timeline: T1 T2 ======================================== ID1 WD1 while(WD1!=QI_DONE) unlock lock WD1=QI_DONE* WD2 while(WD2!=QI_DONE) unlock lock WD1==QI_DONE? ID1=QI_DONE WD2=DONE* reclaim() ID1=FREE WD1=FREE WD2=FREE unlock soft lockup! T2 never sees QI_DONE in WD2 Where: ID = invalidation descriptor WD = wait descriptor * Written by hardware The root of the problem is that the descriptor status QI_DONE flag is used for two conflicting purposes: 1. signal a descriptor is ready for reclaim (to be freed) 2. signal by the hardware that a wait descriptor is complete The solution (in this patch) is state separation by using QI_FREE flag for #1. Once a thread's invalidation descriptors are complete, their status would be set to QI_FREE. The reclaim_free_desc() function would then only free descriptors marked as QI_FREE instead of those marked as QI_DONE. This change ensures that T2 (from the previous example) will correctly observe the completion of its invalidation_wait (marked as QI_DONE).

In the Linux kernel, the following vulnerability has been resolved: drm/stm: Avoid use-after-free issues with crtc and plane ltdc_load() calls functions drm_crtc_init_with_planes(), drm_universal_plane_init() and drm_encoder_init(). These functions should not be called with parameters allocated with devm_kzalloc() to avoid use-after-free issues [1]. Use allocations managed by the DRM framework. Found by Linux Verification Center (linuxtesting.org). [1] https://lore.kernel.org/lkml/u366i76e3qhh3ra5oxrtngjtm2u5lterkekcz6y2jkndhuxzli@diujon4h7qwb/

In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: amdkfd_free_gtt_mem clear the correct pointer Pass pointer reference to amdgpu_bo_unref to clear the correct pointer, otherwise amdgpu_bo_unref clear the local variable, the original pointer not set to NULL, this could cause use-after-free bug.

In the Linux kernel, the following vulnerability has been resolved: drm/xe/hdcp: Check GSC structure validity Sometimes xe_gsc is not initialized when checked at HDCP capability check. Add gsc structure check to avoid null pointer error.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: fix double free issue during amdgpu module unload Flexible endpoints use DIGs from available inflexible endpoints, so only the encoders of inflexible links need to be freed. Otherwise, a double free issue may occur when unloading the amdgpu module. [ 279.190523] RIP: 0010:__slab_free+0x152/0x2f0 [ 279.190577] Call Trace: [ 279.190580] <TASK> [ 279.190582] ? show_regs+0x69/0x80 [ 279.190590] ? die+0x3b/0x90 [ 279.190595] ? do_trap+0xc8/0xe0 [ 279.190601] ? do_error_trap+0x73/0xa0 [ 279.190605] ? __slab_free+0x152/0x2f0 [ 279.190609] ? exc_invalid_op+0x56/0x70 [ 279.190616] ? __slab_free+0x152/0x2f0 [ 279.190642] ? asm_exc_invalid_op+0x1f/0x30 [ 279.190648] ? dcn10_link_encoder_destroy+0x19/0x30 [amdgpu] [ 279.191096] ? __slab_free+0x152/0x2f0 [ 279.191102] ? dcn10_link_encoder_destroy+0x19/0x30 [amdgpu] [ 279.191469] kfree+0x260/0x2b0 [ 279.191474] dcn10_link_encoder_destroy+0x19/0x30 [amdgpu] [ 279.191821] link_destroy+0xd7/0x130 [amdgpu] [ 279.192248] dc_destruct+0x90/0x270 [amdgpu] [ 279.192666] dc_destroy+0x19/0x40 [amdgpu] [ 279.193020] amdgpu_dm_fini+0x16e/0x200 [amdgpu] [ 279.193432] dm_hw_fini+0x26/0x40 [amdgpu] [ 279.193795] amdgpu_device_fini_hw+0x24c/0x400 [amdgpu] [ 279.194108] amdgpu_driver_unload_kms+0x4f/0x70 [amdgpu] [ 279.194436] amdgpu_pci_remove+0x40/0x80 [amdgpu] [ 279.194632] pci_device_remove+0x3a/0xa0 [ 279.194638] device_remove+0x40/0x70 [ 279.194642] device_release_driver_internal+0x1ad/0x210 [ 279.194647] driver_detach+0x4e/0xa0 [ 279.194650] bus_remove_driver+0x6f/0xf0 [ 279.194653] driver_unregister+0x33/0x60 [ 279.194657] pci_unregister_driver+0x44/0x90 [ 279.194662] amdgpu_exit+0x19/0x1f0 [amdgpu] [ 279.194939] __do_sys_delete_module.isra.0+0x198/0x2f0 [ 279.194946] __x64_sys_delete_module+0x16/0x20 [ 279.194950] do_syscall_64+0x58/0x120 [ 279.194954] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 279.194980] </TASK>

In the Linux kernel, the following vulnerability has been resolved: ksmbd: add refcnt to ksmbd_conn struct When sending an oplock break request, opinfo->conn is used, But freed ->conn can be used on multichannel. This patch add a reference count to the ksmbd_conn struct so that it can be freed when it is no longer used.

In the Linux kernel, the following vulnerability has been resolved: bpftool: Fix undefined behavior in qsort(NULL, 0, ...) When netfilter has no entry to display, qsort is called with qsort(NULL, 0, ...). This results in undefined behavior, as UBSan reports: net.c:827:2: runtime error: null pointer passed as argument 1, which is declared to never be null Although the C standard does not explicitly state whether calling qsort with a NULL pointer when the size is 0 constitutes undefined behavior, Section 7.1.4 of the C standard (Use of library functions) mentions: "Each of the following statements applies unless explicitly stated otherwise in the detailed descriptions that follow: If an argument to a function has an invalid value (such as a value outside the domain of the function, or a pointer outside the address space of the program, or a null pointer, or a pointer to non-modifiable storage when the corresponding parameter is not const-qualified) or a type (after promotion) not expected by a function with variable number of arguments, the behavior is undefined." To avoid this, add an early return when nf_link_info is NULL to prevent calling qsort with a NULL pointer.

In the Linux kernel, the following vulnerability has been resolved: platform/x86: x86-android-tablets: Fix use after free on platform_device_register() errors x86_android_tablet_remove() frees the pdevs[] array, so it should not be used after calling x86_android_tablet_remove(). When platform_device_register() fails, store the pdevs[x] PTR_ERR() value into the local ret variable before calling x86_android_tablet_remove() to avoid using pdevs[] after it has been freed.

In the Linux kernel, the following vulnerability has been resolved: i2c: stm32f7: Do not prepare/unprepare clock during runtime suspend/resume In case there is any sort of clock controller attached to this I2C bus controller, for example Versaclock or even an AIC32x4 I2C codec, then an I2C transfer triggered from the clock controller clk_ops .prepare callback may trigger a deadlock on drivers/clk/clk.c prepare_lock mutex. This is because the clock controller first grabs the prepare_lock mutex and then performs the prepare operation, including its I2C access. The I2C access resumes this I2C bus controller via .runtime_resume callback, which calls clk_prepare_enable(), which attempts to grab the prepare_lock mutex again and deadlocks. Since the clock are already prepared since probe() and unprepared in remove(), use simple clk_enable()/clk_disable() calls to enable and disable the clock on runtime suspend and resume, to avoid hitting the prepare_lock mutex.

In the Linux kernel, the following vulnerability has been resolved: drm/v3d: Prevent out of bounds access in performance query extensions Check that the number of perfmons userspace is passing in the copy and reset extensions is not greater than the internal kernel storage where the ids will be copied into.

In the Linux kernel, the following vulnerability has been resolved: ext4: drop ppath from ext4_ext_replay_update_ex() to avoid double-free When calling ext4_force_split_extent_at() in ext4_ext_replay_update_ex(), the 'ppath' is updated but it is the 'path' that is freed, thus potentially triggering a double-free in the following process: ext4_ext_replay_update_ex ppath = path ext4_force_split_extent_at(&ppath) ext4_split_extent_at ext4_ext_insert_extent ext4_ext_create_new_leaf ext4_ext_grow_indepth ext4_find_extent if (depth > path[0].p_maxdepth) kfree(path) ---> path First freed *orig_path = path = NULL ---> null ppath kfree(path) ---> path double-free !!! So drop the unnecessary ppath and use path directly to avoid this problem. And use ext4_find_extent() directly to update path, avoiding unnecessary memory allocation and freeing. Also, propagate the error returned by ext4_find_extent() instead of using strange error codes.

In the Linux kernel, the following vulnerability has been resolved: aoe: fix the potential use-after-free problem in more places For fixing CVE-2023-6270, f98364e92662 ("aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts") makes tx() calling dev_put() instead of doing in aoecmd_cfg_pkts(). It avoids that the tx() runs into use-after-free. Then Nicolai Stange found more places in aoe have potential use-after-free problem with tx(). e.g. revalidate(), aoecmd_ata_rw(), resend(), probe() and aoecmd_cfg_rsp(). Those functions also use aoenet_xmit() to push packet to tx queue. So they should also use dev_hold() to increase the refcnt of skb->dev. On the other hand, moving dev_put() to tx() causes that the refcnt of skb->dev be reduced to a negative value, because corresponding dev_hold() are not called in revalidate(), aoecmd_ata_rw(), resend(), probe(), and aoecmd_cfg_rsp(). This patch fixed this issue.

In the Linux kernel, the following vulnerability has been resolved: media: venus: fix use after free bug in venus_remove due to race condition in venus_probe, core->work is bound with venus_sys_error_handler, which is used to handle error. The code use core->sys_err_done to make sync work. The core->work is started in venus_event_notify. If we call venus_remove, there might be an unfished work. The possible sequence is as follows: CPU0 CPU1 |venus_sys_error_handler venus_remove | hfi_destroy | venus_hfi_destroy | kfree(hdev); | |hfi_reinit |venus_hfi_queues_reinit |//use hdev Fix it by canceling the work in venus_remove.

In the Linux kernel, the following vulnerability has been resolved: vrf: revert "vrf: Remove unnecessary RCU-bh critical section" This reverts commit 504fc6f4f7f681d2a03aa5f68aad549d90eab853. dev_queue_xmit_nit is expected to be called with BH disabled. __dev_queue_xmit has the following: /* Disable soft irqs for various locks below. Also * stops preemption for RCU. */ rcu_read_lock_bh(); VRF must follow this invariant. The referenced commit removed this protection. Which triggered a lockdep warning: ================================ WARNING: inconsistent lock state 6.11.0 #1 Tainted: G W -------------------------------- inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. btserver/134819 [HC0[0]:SC0[0]:HE1:SE1] takes: ffff8882da30c118 (rlock-AF_PACKET){+.?.}-{2:2}, at: tpacket_rcv+0x863/0x3b30 {IN-SOFTIRQ-W} state was registered at: lock_acquire+0x19a/0x4f0 _raw_spin_lock+0x27/0x40 packet_rcv+0xa33/0x1320 __netif_receive_skb_core.constprop.0+0xcb0/0x3a90 __netif_receive_skb_list_core+0x2c9/0x890 netif_receive_skb_list_internal+0x610/0xcc0 [...] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(rlock-AF_PACKET); <Interrupt> lock(rlock-AF_PACKET); *** DEADLOCK *** Call Trace: <TASK> dump_stack_lvl+0x73/0xa0 mark_lock+0x102e/0x16b0 __lock_acquire+0x9ae/0x6170 lock_acquire+0x19a/0x4f0 _raw_spin_lock+0x27/0x40 tpacket_rcv+0x863/0x3b30 dev_queue_xmit_nit+0x709/0xa40 vrf_finish_direct+0x26e/0x340 [vrf] vrf_l3_out+0x5f4/0xe80 [vrf] __ip_local_out+0x51e/0x7a0 [...]

In the Linux kernel, the following vulnerability has been resolved: gso: fix udp gso fraglist segmentation after pull from frag_list Detect gso fraglist skbs with corrupted geometry (see below) and pass these to skb_segment instead of skb_segment_list, as the first can segment them correctly. Valid SKB_GSO_FRAGLIST skbs - consist of two or more segments - the head_skb holds the protocol headers plus first gso_size - one or more frag_list skbs hold exactly one segment - all but the last must be gso_size Optional datapath hooks such as NAT and BPF (bpf_skb_pull_data) can modify these skbs, breaking these invariants. In extreme cases they pull all data into skb linear. For UDP, this causes a NULL ptr deref in __udpv4_gso_segment_list_csum at udp_hdr(seg->next)->dest. Detect invalid geometry due to pull, by checking head_skb size. Don't just drop, as this may blackhole a destination. Convert to be able to pass to regular skb_segment.