In the Linux kernel, the following vulnerability has been resolved: bcachefs: Check for journal entries overruning end of sb clean section Fix a missing bounds check in superblock validation. Note that we don't yet have repair code for this case - repair code for individual items is generally low priority, since the whole superblock is checksummed, validated prior to write, and we have backups.
In the Linux kernel, the following vulnerability has been resolved: KVM: Always flush async #PF workqueue when vCPU is being destroyed Always flush the per-vCPU async #PF workqueue when a vCPU is clearing its completion queue, e.g. when a VM and all its vCPUs is being destroyed. KVM must ensure that none of its workqueue callbacks is running when the last reference to the KVM _module_ is put. Gifting a reference to the associated VM prevents the workqueue callback from dereferencing freed vCPU/VM memory, but does not prevent the KVM module from being unloaded before the callback completes. Drop the misguided VM refcount gifting, as calling kvm_put_kvm() from async_pf_execute() if kvm_put_kvm() flushes the async #PF workqueue will result in deadlock. async_pf_execute() can't return until kvm_put_kvm() finishes, and kvm_put_kvm() can't return until async_pf_execute() finishes: WARNING: CPU: 8 PID: 251 at virt/kvm/kvm_main.c:1435 kvm_put_kvm+0x2d/0x320 [kvm] Modules linked in: vhost_net vhost vhost_iotlb tap kvm_intel kvm irqbypass CPU: 8 PID: 251 Comm: kworker/8:1 Tainted: G W 6.6.0-rc1-e7af8d17224a-x86/gmem-vm #119 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Workqueue: events async_pf_execute [kvm] RIP: 0010:kvm_put_kvm+0x2d/0x320 [kvm] Call Trace: <TASK> async_pf_execute+0x198/0x260 [kvm] process_one_work+0x145/0x2d0 worker_thread+0x27e/0x3a0 kthread+0xba/0xe0 ret_from_fork+0x2d/0x50 ret_from_fork_asm+0x11/0x20 </TASK> ---[ end trace 0000000000000000 ]--- INFO: task kworker/8:1:251 blocked for more than 120 seconds. Tainted: G W 6.6.0-rc1-e7af8d17224a-x86/gmem-vm #119 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/8:1 state:D stack:0 pid:251 ppid:2 flags:0x00004000 Workqueue: events async_pf_execute [kvm] Call Trace: <TASK> __schedule+0x33f/0xa40 schedule+0x53/0xc0 schedule_timeout+0x12a/0x140 __wait_for_common+0x8d/0x1d0 __flush_work.isra.0+0x19f/0x2c0 kvm_clear_async_pf_completion_queue+0x129/0x190 [kvm] kvm_arch_destroy_vm+0x78/0x1b0 [kvm] kvm_put_kvm+0x1c1/0x320 [kvm] async_pf_execute+0x198/0x260 [kvm] process_one_work+0x145/0x2d0 worker_thread+0x27e/0x3a0 kthread+0xba/0xe0 ret_from_fork+0x2d/0x50 ret_from_fork_asm+0x11/0x20 </TASK> If kvm_clear_async_pf_completion_queue() actually flushes the workqueue, then there's no need to gift async_pf_execute() a reference because all invocations of async_pf_execute() will be forced to complete before the vCPU and its VM are destroyed/freed. And that in turn fixes the module unloading bug as __fput() won't do module_put() on the last vCPU reference until the vCPU has been freed, e.g. if closing the vCPU file also puts the last reference to the KVM module. Note that kvm_check_async_pf_completion() may also take the work item off the completion queue and so also needs to flush the work queue, as the work will not be seen by kvm_clear_async_pf_completion_queue(). Waiting on the workqueue could theoretically delay a vCPU due to waiting for the work to complete, but that's a very, very small chance, and likely a very small delay. kvm_arch_async_page_present_queued() unconditionally makes a new request, i.e. will effectively delay entering the guest, so the remaining work is really just: trace_kvm_async_pf_completed(addr, cr2_or_gpa); __kvm_vcpu_wake_up(vcpu); mmput(mm); and mmput() can't drop the last reference to the page tables if the vCPU is still alive, i.e. the vCPU won't get stuck tearing down page tables. Add a helper to do the flushing, specifically to deal with "wakeup all" work items, as they aren't actually work items, i.e. are never placed in a workqueue. Trying to flush a bogus workqueue entry rightly makes __flush_work() complain (kudos to whoever added that sanity check). Note, commit 5f6de5cbebee ("KVM: Prevent module exit until al ---truncated---
The Network Lock Manager (NLM) protocol implementation in the NFS client functionality in the Linux kernel before 3.0 allows local users to cause a denial of service (system hang) via a LOCK_UN flock system call.
The gfs2_fallocate function in fs/gfs2/file.c in the Linux kernel before 3.0-rc1 does not ensure that the size of a chunk allocation is a multiple of the block size, which allows local users to cause a denial of service (BUG and system crash) by arranging for all resource groups to have too little free space.
net/core/net_namespace.c in the Linux kernel 2.6.32 and earlier does not properly handle a high rate of creation and cleanup of network namespaces, which makes it easier for remote attackers to cause a denial of service (memory consumption) via requests to a daemon that requires a separate namespace per connection, as demonstrated by vsftpd.
The epoll implementation in the Linux kernel 2.6.37.2 and earlier does not properly traverse a tree of epoll file descriptors, which allows local users to cause a denial of service (CPU consumption) via a crafted application that makes epoll_create and epoll_ctl system calls.
fs/eventpoll.c in the Linux kernel before 2.6.38 places epoll file descriptors within other epoll data structures without properly checking for (1) closed loops or (2) deep chains, which allows local users to cause a denial of service (deadlock or stack memory consumption) via a crafted application that makes epoll_create and epoll_ctl system calls.
mm/huge_memory.c in the Linux kernel before 2.6.38-rc5 does not prevent creation of a transparent huge page (THP) during the existence of a temporary stack for an exec system call, which allows local users to cause a denial of service (memory consumption) or possibly have unspecified other impact via a crafted application.
A locally locally exploitable DOS vulnerability was found in pax-linux versions 2.6.32.33-test79.patch, 2.6.38-test3.patch, and 2.6.37.4-test14.patch. A bad bounds check in arch_get_unmapped_area_topdown triggered by programs doing an mmap after a MAP_GROWSDOWN mmap will create an infinite loop condition without releasing the VM semaphore eventually leading to a system crash.
The SCTP socket buffer used by a userspace application is not accounted by the cgroups subsystem. An attacker can use this flaw to cause a denial of service attack. Kernel 3.10.x and 4.18.x branches are believed to be vulnerable.
The blk_rq_map_user_iov function in block/blk-map.c in the Linux kernel before 2.6.37-rc7 allows local users to cause a denial of service (panic) via a zero-length I/O request in a device ioctl to a SCSI device, related to an unaligned map. NOTE: this vulnerability exists because of an incomplete fix for CVE-2010-4163.
The KVM implementation in the Linux kernel before 2.6.36 does not properly reload the FS and GS segment registers, which allows host OS users to cause a denial of service (host OS crash) via a KVM_RUN ioctl call in conjunction with a modified Local Descriptor Table (LDT).
The wait_for_unix_gc function in net/unix/garbage.c in the Linux kernel before 2.6.37-rc3-next-20101125 does not properly select times for garbage collection of inflight sockets, which allows local users to cause a denial of service (system hang) via crafted use of the socketpair and sendmsg system calls for SOCK_SEQPACKET sockets.
fs/exec.c in the Linux kernel before 2.6.37 does not enable the OOM Killer to assess use of stack memory by arrays representing the (1) arguments and (2) environment, which allows local users to cause a denial of service (memory consumption) via a crafted exec system call, aka an "OOM dodging issue," a related issue to CVE-2010-3858.
The sctp_auth_asoc_get_hmac function in net/sctp/auth.c in the Linux kernel before 2.6.36 does not properly validate the hmac_ids array of an SCTP peer, which allows remote attackers to cause a denial of service (memory corruption and panic) via a crafted value in the last element of this array.
The socket implementation in net/core/sock.c in the Linux kernel before 2.6.34 does not properly manage a backlog of received packets, which allows remote attackers to cause a denial of service (memory consumption) by sending a large amount of network traffic, as demonstrated by netperf UDP tests.
In the Linux kernel, the following vulnerability has been resolved: x86/xen: Drop USERGS_SYSRET64 paravirt call commit afd30525a659ac0ae0904f0cb4a2ca75522c3123 upstream. USERGS_SYSRET64 is used to return from a syscall via SYSRET, but a Xen PV guest will nevertheless use the IRET hypercall, as there is no sysret PV hypercall defined. So instead of testing all the prerequisites for doing a sysret and then mangling the stack for Xen PV again for doing an iret just use the iret exit from the beginning. This can easily be done via an ALTERNATIVE like it is done for the sysenter compat case already. It should be noted that this drops the optimization in Xen for not restoring a few registers when returning to user mode, but it seems as if the saved instructions in the kernel more than compensate for this drop (a kernel build in a Xen PV guest was slightly faster with this patch applied). While at it remove the stale sysret32 remnants. [ pawan: Brad Spengler and Salvatore Bonaccorso <carnil@debian.org> reported a problem with the 5.10 backport commit edc702b4a820 ("x86/entry_64: Add VERW just before userspace transition"). When CONFIG_PARAVIRT_XXL=y, CLEAR_CPU_BUFFERS is not executed in syscall_return_via_sysret path as USERGS_SYSRET64 is runtime patched to: .cpu_usergs_sysret64 = { 0x0f, 0x01, 0xf8, 0x48, 0x0f, 0x07 }, // swapgs; sysretq which is missing CLEAR_CPU_BUFFERS. It turns out dropping USERGS_SYSRET64 simplifies the code, allowing CLEAR_CPU_BUFFERS to be explicitly added to syscall_return_via_sysret path. Below is with CONFIG_PARAVIRT_XXL=y and this patch applied: syscall_return_via_sysret: ... <+342>: swapgs <+345>: xchg %ax,%ax <+347>: verw -0x1a2(%rip) <------ <+354>: sysretq ]
net/unix/af_unix.c in the Linux kernel 2.6.31.4 and earlier allows local users to cause a denial of service (system hang) by creating an abstract-namespace AF_UNIX listening socket, performing a shutdown operation on this socket, and then performing a series of connect operations to this socket.
In the Linux kernel, the following vulnerability has been resolved: pipe: wakeup wr_wait after setting max_usage Commit c73be61cede5 ("pipe: Add general notification queue support") a regression was introduced that would lock up resized pipes under certain conditions. See the reproducer in [1]. The commit resizing the pipe ring size was moved to a different function, doing that moved the wakeup for pipe->wr_wait before actually raising pipe->max_usage. If a pipe was full before the resize occured it would result in the wakeup never actually triggering pipe_write. Set @max_usage and @nr_accounted before waking writers if this isn't a watch queue. [Christian Brauner <brauner@kernel.org>: rewrite to account for watch queues]
In the Linux kernel, the following vulnerability has been resolved: jfs: fix slab-out-of-bounds Read in dtSearch Currently while searching for current page in the sorted entry table of the page there is a out of bound access. Added a bound check to fix the error. Dave: Set return code to -EIO
The IPv6 implementation in the Linux kernel before 6.3 has a net/ipv6/route.c max_size threshold that can be consumed easily, e.g., leading to a denial of service (network is unreachable errors) when IPv6 packets are sent in a loop via a raw socket.
The shmem_delete_inode function in mm/shmem.c in the tmpfs implementation in the Linux kernel before 2.6.26.1 allows local users to cause a denial of service (system crash) via a certain sequence of file create, remove, and overwrite operations, as demonstrated by the insserv program, related to allocation of "useless pages" and improper maintenance of the i_blocks count.
The bio_map_user_iov and bio_unmap_user functions in block/bio.c in the Linux kernel before 4.13.8 do unbalanced refcounting when a SCSI I/O vector has small consecutive buffers belonging to the same page. The bio_add_pc_page function merges them into one, but the page reference is never dropped. This causes a memory leak and possible system lockup (exploitable against the host OS by a guest OS user, if a SCSI disk is passed through to a virtual machine) due to an out-of-memory condition.
A flaw was found in the way memory resources were freed in the unix_stream_recvmsg function in the Linux kernel when a signal was pending. This flaw allows an unprivileged local user to crash the system by exhausting available memory. The highest threat from this vulnerability is to system availability.
Certain WithSecure products allow Denial of Service via the aepack archive unpack handler. This affects WithSecure Client Security 15, WithSecure Server Security 15, WithSecure Email and Server Security 15, WithSecure Elements Endpoint Protection 17 and later, WithSecure Client Security for Mac 15, WithSecure Elements Endpoint Protection for Mac 17 and later, Linux Security 64 12.0 , Linux Protection 12.0, and WithSecure Atlant (formerly F-Secure Atlant) 1.0.35-1.
ext4_protect_reserved_inode in fs/ext4/block_validity.c in the Linux kernel through 5.5.3 allows attackers to cause a denial of service (soft lockup) via a crafted journal size.
A use-after-free flaw was found in btrfs_get_dev_args_from_path in fs/btrfs/volumes.c in btrfs file-system in the Linux Kernel. This flaw allows a local attacker with special privileges to cause a system crash or leak internal kernel information
Certain WithSecure products allow a remote crash of a scanning engine via unpacking of crafted data files. This affects WithSecure Client Security 15, WithSecure Server Security 15, WithSecure Email and Server Security 15, WithSecure Elements Endpoint Protection 17 and later, WithSecure Client Security for Mac 15, WithSecure Elements Endpoint Protection for Mac 17 and later, Linux Security 64 12.0 , Linux Protection 12.0, and WithSecure Atlant (formerly F-Secure Atlant) 1.0.35-1.
Certain WithSecure products allow a remote crash of a scanning engine via processing of a compressed file. This affects WithSecure Client Security 15, WithSecure Server Security 15, WithSecure Email and Server Security 15, WithSecure Elements Endpoint Protection 17 and later, WithSecure Client Security for Mac 15, WithSecure Elements Endpoint Protection for Mac 17 and later, Linux Security 64 12.0 , Linux Protection 12.0, and WithSecure Atlant (formerly F-Secure Atlant) 1.0.35-1.
Certain WithSecure products allow a remote crash of a scanning engine via processing of an import struct in a PE file. This affects WithSecure Client Security 15, WithSecure Server Security 15, WithSecure Email and Server Security 15, WithSecure Elements Endpoint Protection 17 and later, WithSecure Client Security for Mac 15, WithSecure Elements Endpoint Protection for Mac 17 and later, Linux Security 64 12.0 , Linux Protection 12.0, and WithSecure Atlant (formerly F-Secure Atlant) 1.0.35-1.
Certain WithSecure products allow a remote crash of a scanning engine via unpacking of a PE file. This affects WithSecure Client Security 15, WithSecure Server Security 15, WithSecure Email and Server Security 15, WithSecure Elements Endpoint Protection 17 and later, WithSecure Client Security for Mac 15, WithSecure Elements Endpoint Protection for Mac 17 and later, Linux Security 64 12.0 , Linux Protection 12.0, and WithSecure Atlant (formerly F-Secure Atlant) 1.0.35-1.
Certain WithSecure products allow a remote crash of a scanning engine via decompression of crafted data files. This affects WithSecure Client Security 15, WithSecure Server Security 15, WithSecure Email and Server Security 15, WithSecure Elements Endpoint Protection 17 and later, WithSecure Client Security for Mac 15, WithSecure Elements Endpoint Protection for Mac 17 and later, Linux Security 64 12.0 , Linux Protection 12.0, and WithSecure Atlant (formerly F-Secure Atlant) 1.0.35-1.
IBM TXSeries for Multiplatforms, 8.1, 8.2, and 9.1, CICS TX Standard CICS TX Advanced 10.1 and 11.1 could allow a privileged user to cause a denial of service due to uncontrolled resource consumption. IBM X-Force ID: 266016.
IBM TXSeries for Multiplatforms 8.1, 8.2, and 9.1 is vulnerable to a denial of service, caused by improper enforcement of the timeout on individual read operations. By conducting a slowloris-type attacks, a remote attacker could exploit this vulnerability to cause a denial of service. IBM X-Force ID: 262905.
A flaw was found within the handling of SMB2_READ commands in the kernel ksmbd module. The issue results from not releasing memory after its effective lifetime. An attacker can leverage this to create a denial-of-service condition on affected installations of Linux. Authentication is not required to exploit this vulnerability, but only systems with ksmbd enabled are vulnerable.
An issue was discovered in the Linux kernel before 5.4.7. The prb_calc_retire_blk_tmo() function in net/packet/af_packet.c can result in a denial of service (CPU consumption and soft lockup) in a certain failure case involving TPACKET_V3, aka CID-b43d1f9f7067.
kernel/sched/fair.c in the Linux kernel before 5.3.9, when cpu.cfs_quota_us is used (e.g., with Kubernetes), allows attackers to cause a denial of service against non-cpu-bound applications by generating a workload that triggers unwanted slice expiration, aka CID-de53fd7aedb1. (In other words, although this slice expiration would typically be seen with benign workloads, it is possible that an attacker could calculate how many stray requests are required to force an entire Kubernetes cluster into a low-performance state caused by slice expiration, and ensure that a DDoS attack sent that number of stray requests. An attack does not affect the stability of the kernel; it only causes mismanagement of application execution.)
Closing of an event channel in the Linux kernel can result in a deadlock. This happens when the close is being performed in parallel to an unrelated Xen console action and the handling of a Xen console interrupt in an unprivileged guest. The closing of an event channel is e.g. triggered by removal of a paravirtual device on the other side. As this action will cause console messages to be issued on the other side quite often, the chance of triggering the deadlock is not neglectable. Note that 32-bit Arm-guests are not affected, as the 32-bit Linux kernel on Arm doesn't use queued-RW-locks, which are required to trigger the issue (on Arm32 a waiting writer doesn't block further readers to get the lock).
A vulnerability in Hitachi Command Suite 7.x and 8.x before 8.7.0-00 allows an unauthenticated remote user to trigger a denial of service (DoS) condition because of Uncontrolled Resource Consumption.
Jonathan Looney discovered that the TCP retransmission queue implementation in tcp_fragment in the Linux kernel could be fragmented when handling certain TCP Selective Acknowledgment (SACK) sequences. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit f070ef2ac66716357066b683fb0baf55f8191a2e.
An issue was discovered in xfs_setattr_nonsize in fs/xfs/xfs_iops.c in the Linux kernel through 5.2.9. XFS partially wedges when a chgrp fails on account of being out of disk quota. xfs_setattr_nonsize is failing to unlock the ILOCK after the xfs_qm_vop_chown_reserve call fails. This is primarily a local DoS attack vector, but it might result as well in remote DoS if the XFS filesystem is exported for instance via NFS.
In the Linux kernel, the following vulnerability has been resolved: lan966x: Fix crash when adding interface under a lag There is a crash when adding one of the lan966x interfaces under a lag interface. The issue can be reproduced like this: ip link add name bond0 type bond miimon 100 mode balance-xor ip link set dev eth0 master bond0 The reason is because when adding a interface under the lag it would go through all the ports and try to figure out which other ports are under that lag interface. And the issue is that lan966x can have ports that are NULL pointer as they are not probed. So then iterating over these ports it would just crash as they are NULL pointers. The fix consists in actually checking for NULL pointers before accessing something from the ports. Like we do in other places.
Rocket Software UniData versions prior to 8.2.4 build 3003 and UniVerse versions prior to 11.3.5 build 1001 or 12.2.1 build 2002 suffer from a memory-exhaustion issue, where a decompression routine will allocate increasing amounts of memory until all system memory is exhausted and the forked process crashes.
Multiple memory leaks in error paths in fs/xfs/xfs_attr_list.c in the Linux kernel before 4.5.1 allow local users to cause a denial of service (memory consumption) via crafted XFS filesystem operations.
A heap overflow flaw was found in the Linux kernel, all versions 3.x.x and 4.x.x before 4.18.0, in Marvell WiFi chip driver. The vulnerability allows a remote attacker to cause a system crash, resulting in a denial of service, or execute arbitrary code. The highest threat with this vulnerability is with the availability of the system. If code execution occurs, the code will run with the permissions of root. This will affect both confidentiality and integrity of files on the system.
A memory leak flaw was found in the Linux kernel's ccp_run_aes_gcm_cmd() function that allows an attacker to cause a denial of service. The vulnerability is similar to the older CVE-2019-18808. The highest threat from this vulnerability is to system availability.
A memory overflow vulnerability was found in the Linux kernel’s ipc functionality of the memcg subsystem, in the way a user calls the semget function multiple times, creating semaphores. This flaw allows a local user to starve the resources, causing a denial of service. The highest threat from this vulnerability is to system availability.
A lack of CPU resource in the Linux kernel tracing module functionality in versions prior to 5.14-rc3 was found in the way user uses trace ring buffer in a specific way. Only privileged local users (with CAP_SYS_ADMIN capability) could use this flaw to starve the resources causing denial of service.
Uncontrolled resource consumption in some Intel(R) Aptio* V UEFI Firmware Integrator Tools may allow an authenticated user to potentially enable denial of service via local access.
A vulnerability in Trend Micro Smart Protection Server (Standalone) 3.x could allow an unauthenticated remote attacker to manipulate the product to send a large number of specially crafted HTTP requests to potentially cause the file system to fill up, eventually causing a denial of service (DoS) situation.