In the Linux kernel, the following vulnerability has been resolved: EDAC/thunderx: Fix possible out-of-bounds string access Enabling -Wstringop-overflow globally exposes a warning for a common bug in the usage of strncat(): drivers/edac/thunderx_edac.c: In function 'thunderx_ocx_com_threaded_isr': drivers/edac/thunderx_edac.c:1136:17: error: 'strncat' specified bound 1024 equals destination size [-Werror=stringop-overflow=] 1136 | strncat(msg, other, OCX_MESSAGE_SIZE); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ... 1145 | strncat(msg, other, OCX_MESSAGE_SIZE); ... 1150 | strncat(msg, other, OCX_MESSAGE_SIZE); ... Apparently the author of this driver expected strncat() to behave the way that strlcat() does, which uses the size of the destination buffer as its third argument rather than the length of the source buffer. The result is that there is no check on the size of the allocated buffer. Change it to strlcat(). [ bp: Trim compiler output, fixup commit message. ]
The do_shmat function in ipc/shm.c in the Linux kernel through 4.9.12 does not restrict the address calculated by a certain rounding operation, which allows local users to map page zero, and consequently bypass a protection mechanism that exists for the mmap system call, by making crafted shmget and shmat system calls in a privileged context.
In the Linux kernel, the following vulnerability has been resolved: serial: 8250: omap: Don't skip resource freeing if pm_runtime_resume_and_get() failed Returning an error code from .remove() makes the driver core emit the little helpful error message: remove callback returned a non-zero value. This will be ignored. and then remove the device anyhow. So all resources that were not freed are leaked in this case. Skipping serial8250_unregister_port() has the potential to keep enough of the UART around to trigger a use-after-free. So replace the error return (and with it the little helpful error message) by a more useful error message and continue to cleanup.
In the Linux kernel, the following vulnerability has been resolved: mctp: perform route lookups under a RCU read-side lock Our current route lookups (mctp_route_lookup and mctp_route_lookup_null) traverse the net's route list without the RCU read lock held. This means the route lookup is subject to preemption, resulting in an potential grace period expiry, and so an eventual kfree() while we still have the route pointer. Add the proper read-side critical section locks around the route lookups, preventing premption and a possible parallel kfree. The remaining net->mctp.routes accesses are already under a rcu_read_lock, or protected by the RTNL for updates. Based on an analysis from Sili Luo <rootlab@huawei.com>, where introducing a delay in the route lookup could cause a UAF on simultaneous sendmsg() and route deletion.
rbash in Bash before 4.4-beta2 did not prevent the shell user from modifying BASH_CMDS, thus allowing the user to execute any command with the permissions of the shell.
In the Linux kernel before 6.4.12, amdgpu_cs_wait_all_fences in drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c has a fence use-after-free.
v86d before 0.1.10 do not verify if received netlink messages are sent by the kernel. This could allow unprivileged users to manipulate the video mode and potentially other consequences.
There is a possible tty hijacking in shadow 4.x before 4.1.5 and sudo 1.x before 1.7.4 via "su - user -c program". The user session can be escaped to the parent session by using the TIOCSTI ioctl to push characters into the input buffer to be read by the next process.
In the Linux kernel, the following vulnerability has been resolved: nvmem: Fix shift-out-of-bound (UBSAN) with byte size cells If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0); will become undefined behavior because nbits modulo BITS_PER_BYTE is 0, and we subtract one from that making a large number that is then shifted more than the number of bits that fit into an unsigned long. UBSAN reports this problem: UBSAN: shift-out-of-bounds in drivers/nvmem/core.c:1386:8 shift exponent 64 is too large for 64-bit type 'unsigned long' CPU: 6 PID: 7 Comm: kworker/u16:0 Not tainted 5.15.0-rc3+ #9 Hardware name: Google Lazor (rev3+) with KB Backlight (DT) Workqueue: events_unbound deferred_probe_work_func Call trace: dump_backtrace+0x0/0x170 show_stack+0x24/0x30 dump_stack_lvl+0x64/0x7c dump_stack+0x18/0x38 ubsan_epilogue+0x10/0x54 __ubsan_handle_shift_out_of_bounds+0x180/0x194 __nvmem_cell_read+0x1ec/0x21c nvmem_cell_read+0x58/0x94 nvmem_cell_read_variable_common+0x4c/0xb0 nvmem_cell_read_variable_le_u32+0x40/0x100 a6xx_gpu_init+0x170/0x2f4 adreno_bind+0x174/0x284 component_bind_all+0xf0/0x264 msm_drm_bind+0x1d8/0x7a0 try_to_bring_up_master+0x164/0x1ac __component_add+0xbc/0x13c component_add+0x20/0x2c dp_display_probe+0x340/0x384 platform_probe+0xc0/0x100 really_probe+0x110/0x304 __driver_probe_device+0xb8/0x120 driver_probe_device+0x4c/0xfc __device_attach_driver+0xb0/0x128 bus_for_each_drv+0x90/0xdc __device_attach+0xc8/0x174 device_initial_probe+0x20/0x2c bus_probe_device+0x40/0xa4 deferred_probe_work_func+0x7c/0xb8 process_one_work+0x128/0x21c process_scheduled_works+0x40/0x54 worker_thread+0x1ec/0x2a8 kthread+0x138/0x158 ret_from_fork+0x10/0x20 Fix it by making sure there are any bits to mask out.
In the Linux kernel before 2.6.34, a range check issue in drivers/gpu/drm/radeon/atombios.c could cause an off by one (buffer overflow) problem. NOTE: At least one Linux maintainer believes that this CVE is incorrectly assigned and should be rejected because the value is hard coded and are not user-controllable where it is used
Exim 4.72 and earlier allows local users to gain privileges by leveraging the ability of the exim user account to specify an alternate configuration file with a directive that contains arbitrary commands, as demonstrated by the spool_directory directive.
The iowarrior_write function in drivers/usb/misc/iowarrior.c in the Linux kernel before 2.6.37 does not properly allocate memory, which might allow local users to trigger a heap-based buffer overflow, and consequently cause a denial of service or gain privileges, via a long report.
A buffer overflow was discovered in the GNU C Library's dynamic loader ld.so while processing the GLIBC_TUNABLES environment variable. This issue could allow a local attacker to use maliciously crafted GLIBC_TUNABLES environment variables when launching binaries with SUID permission to execute code with elevated privileges.
Buffer overflow in the kvm_vcpu_ioctl_x86_setup_mce function in arch/x86/kvm/x86.c in the KVM subsystem in the Linux kernel before 2.6.32-rc7 allows local users to cause a denial of service (memory corruption) or possibly gain privileges via a KVM_X86_SETUP_MCE IOCTL request that specifies a large number of Machine Check Exception (MCE) banks.
udisks before 1.0.3 allows a local user to load arbitrary Linux kernel modules.
A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation. When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue(). We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.
In the Linux Kernel before versions 4.20.8 and 4.19.21 a use-after-free error in the "sctp_sendmsg()" function (net/sctp/socket.c) when handling SCTP_SENDALL flag can be exploited to corrupt memory.
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: Fix use-after-free bugs caused by sco_sock_timeout When the sco connection is established and then, the sco socket is releasing, timeout_work will be scheduled to judge whether the sco disconnection is timeout. The sock will be deallocated later, but it is dereferenced again in sco_sock_timeout. As a result, the use-after-free bugs will happen. The root cause is shown below: Cleanup Thread | Worker Thread sco_sock_release | sco_sock_close | __sco_sock_close | sco_sock_set_timer | schedule_delayed_work | sco_sock_kill | (wait a time) sock_put(sk) //FREE | sco_sock_timeout | sock_hold(sk) //USE The KASAN report triggered by POC is shown below: [ 95.890016] ================================================================== [ 95.890496] BUG: KASAN: slab-use-after-free in sco_sock_timeout+0x5e/0x1c0 [ 95.890755] Write of size 4 at addr ffff88800c388080 by task kworker/0:0/7 ... [ 95.890755] Workqueue: events sco_sock_timeout [ 95.890755] Call Trace: [ 95.890755] <TASK> [ 95.890755] dump_stack_lvl+0x45/0x110 [ 95.890755] print_address_description+0x78/0x390 [ 95.890755] print_report+0x11b/0x250 [ 95.890755] ? __virt_addr_valid+0xbe/0xf0 [ 95.890755] ? sco_sock_timeout+0x5e/0x1c0 [ 95.890755] kasan_report+0x139/0x170 [ 95.890755] ? update_load_avg+0xe5/0x9f0 [ 95.890755] ? sco_sock_timeout+0x5e/0x1c0 [ 95.890755] kasan_check_range+0x2c3/0x2e0 [ 95.890755] sco_sock_timeout+0x5e/0x1c0 [ 95.890755] process_one_work+0x561/0xc50 [ 95.890755] worker_thread+0xab2/0x13c0 [ 95.890755] ? pr_cont_work+0x490/0x490 [ 95.890755] kthread+0x279/0x300 [ 95.890755] ? pr_cont_work+0x490/0x490 [ 95.890755] ? kthread_blkcg+0xa0/0xa0 [ 95.890755] ret_from_fork+0x34/0x60 [ 95.890755] ? kthread_blkcg+0xa0/0xa0 [ 95.890755] ret_from_fork_asm+0x11/0x20 [ 95.890755] </TASK> [ 95.890755] [ 95.890755] Allocated by task 506: [ 95.890755] kasan_save_track+0x3f/0x70 [ 95.890755] __kasan_kmalloc+0x86/0x90 [ 95.890755] __kmalloc+0x17f/0x360 [ 95.890755] sk_prot_alloc+0xe1/0x1a0 [ 95.890755] sk_alloc+0x31/0x4e0 [ 95.890755] bt_sock_alloc+0x2b/0x2a0 [ 95.890755] sco_sock_create+0xad/0x320 [ 95.890755] bt_sock_create+0x145/0x320 [ 95.890755] __sock_create+0x2e1/0x650 [ 95.890755] __sys_socket+0xd0/0x280 [ 95.890755] __x64_sys_socket+0x75/0x80 [ 95.890755] do_syscall_64+0xc4/0x1b0 [ 95.890755] entry_SYSCALL_64_after_hwframe+0x67/0x6f [ 95.890755] [ 95.890755] Freed by task 506: [ 95.890755] kasan_save_track+0x3f/0x70 [ 95.890755] kasan_save_free_info+0x40/0x50 [ 95.890755] poison_slab_object+0x118/0x180 [ 95.890755] __kasan_slab_free+0x12/0x30 [ 95.890755] kfree+0xb2/0x240 [ 95.890755] __sk_destruct+0x317/0x410 [ 95.890755] sco_sock_release+0x232/0x280 [ 95.890755] sock_close+0xb2/0x210 [ 95.890755] __fput+0x37f/0x770 [ 95.890755] task_work_run+0x1ae/0x210 [ 95.890755] get_signal+0xe17/0xf70 [ 95.890755] arch_do_signal_or_restart+0x3f/0x520 [ 95.890755] syscall_exit_to_user_mode+0x55/0x120 [ 95.890755] do_syscall_64+0xd1/0x1b0 [ 95.890755] entry_SYSCALL_64_after_hwframe+0x67/0x6f [ 95.890755] [ 95.890755] The buggy address belongs to the object at ffff88800c388000 [ 95.890755] which belongs to the cache kmalloc-1k of size 1024 [ 95.890755] The buggy address is located 128 bytes inside of [ 95.890755] freed 1024-byte region [ffff88800c388000, ffff88800c388400) [ 95.890755] [ 95.890755] The buggy address belongs to the physical page: [ 95.890755] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88800c38a800 pfn:0xc388 [ 95.890755] head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 95.890755] ano ---truncated---
In the Linux kernel through 4.20.11, af_alg_release() in crypto/af_alg.c neglects to set a NULL value for a certain structure member, which leads to a use-after-free in sockfs_setattr.
Google Chrome before 7.0.517.41 does not properly handle animated GIF images, which allows remote attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact via a crafted image.
In the Linux kernel before 4.20.12, net/ipv4/netfilter/nf_nat_snmp_basic_main.c in the SNMP NAT module has insufficient ASN.1 length checks (aka an array index error), making out-of-bounds read and write operations possible, leading to an OOPS or local privilege escalation. This affects snmp_version and snmp_helper.
The rds_page_copy_user function in net/rds/page.c in the Reliable Datagram Sockets (RDS) protocol implementation in the Linux kernel before 2.6.36 does not properly validate addresses obtained from user space, which allows local users to gain privileges via crafted use of the sendmsg and recvmsg system calls.
In the Linux kernel, the following vulnerability has been resolved: KVM: Explicitly verify target vCPU is online in kvm_get_vcpu() Explicitly verify the target vCPU is fully online _prior_ to clamping the index in kvm_get_vcpu(). If the index is "bad", the nospec clamping will generate '0', i.e. KVM will return vCPU0 instead of NULL. In practice, the bug is unlikely to cause problems, as it will only come into play if userspace or the guest is buggy or misbehaving, e.g. KVM may send interrupts to vCPU0 instead of dropping them on the floor. However, returning vCPU0 when it shouldn't exist per online_vcpus is problematic now that KVM uses an xarray for the vCPUs array, as KVM needs to insert into the xarray before publishing the vCPU to userspace (see commit c5b077549136 ("KVM: Convert the kvm->vcpus array to a xarray")), i.e. before vCPU creation is guaranteed to succeed. As a result, incorrectly providing access to vCPU0 will trigger a use-after-free if vCPU0 is dereferenced and kvm_vm_ioctl_create_vcpu() bails out of vCPU creation due to an error and frees vCPU0. Commit afb2acb2e3a3 ("KVM: Fix vcpu_array[0] races") papered over that issue, but in doing so introduced an unsolvable teardown conundrum. Preventing accesses to vCPU0 before it's fully online will allow reverting commit afb2acb2e3a3, without re-introducing the vcpu_array[0] UAF race.
The compat_alloc_user_space functions in include/asm/compat.h files in the Linux kernel before 2.6.36-rc4-git2 on 64-bit platforms do not properly allocate the userspace memory required for the 32-bit compatibility layer, which allows local users to gain privileges by leveraging the ability of the compat_mc_getsockopt function (aka the MCAST_MSFILTER getsockopt support) to control a certain length value, related to a "stack pointer underflow" issue, as exploited in the wild in September 2010.
VMware Workspace ONE Access, Identity Manager and vRealize Automation contain a privilege escalation vulnerability due to improper permissions in support scripts. A malicious actor with local access can escalate privileges to 'root'.
Integer overflow in the SCTP_SOCKOPT_DEBUG_NAME SCTP socket option in socket.c in the Linux kernel 2.4.25 and earlier allows local users to execute arbitrary code via an optlen value of -1, which causes kmalloc to allocate 0 bytes of memory.
io_uring use work_flags to determine which identity need to grab from the calling process to make sure it is consistent with the calling process when executing IORING_OP. Some operations are missing some types, which can lead to incorrect reference counts which can then lead to a double free. We recommend upgrading the kernel past commit df3f3bb5059d20ef094d6b2f0256c4bf4127a859
VMware Horizon Agent for Linux (prior to 22.x) contains a local privilege escalation that allows a user to escalate to root due to a vulnerable configuration file.
Buffer overflow in the ecryptfs_uid_hash macro in fs/ecryptfs/messaging.c in the eCryptfs subsystem in the Linux kernel before 2.6.35 might allow local users to gain privileges or cause a denial of service (system crash) via unspecified vectors.
The gfs2_dirent_find_space function in fs/gfs2/dir.c in the Linux kernel before 2.6.35 uses an incorrect size value in calculations associated with sentinel directory entries, which allows local users to cause a denial of service (NULL pointer dereference and panic) and possibly have unspecified other impact by renaming a file in a GFS2 filesystem, related to the gfs2_rename function in fs/gfs2/ops_inode.c.
The keyctl_session_to_parent function in security/keys/keyctl.c in the Linux kernel 2.6.35.4 and earlier expects that a certain parent session keyring exists, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a KEYCTL_SESSION_TO_PARENT argument to the keyctl function.
A flaw was discovered in gfs2 file system’s handling of acls (access control lists). An unprivileged local attacker could exploit this flaw to gain access or execute any file stored in the gfs2 file system.
IBM Security Guardium 11.3, 11.4, and 11.5 could allow a local user to obtain elevated privileges due to incorrect authorization checks. IBM X-Force ID: 216753.
The ip_cmsg_recv_checksum function in net/ipv4/ip_sockglue.c in the Linux kernel before 4.10.1 has incorrect expectations about skb data layout, which allows local users to cause a denial of service (buffer over-read) or possibly have unspecified other impact via crafted system calls, as demonstrated by use of the MSG_MORE flag in conjunction with loopback UDP transmission.
The DNS resolution functionality in the CIFS implementation in the Linux kernel before 2.6.35, when CONFIG_CIFS_DFS_UPCALL is enabled, relies on a user's keyring for the dns_resolver upcall in the cifs.upcall userspace helper, which allows local users to spoof the results of DNS queries and perform arbitrary CIFS mounts via vectors involving an add_key call, related to a "cache stuffing" issue and MS-DFS referrals.
A use-after-free vulnerability in the Linux kernel's af_unix component can be exploited to achieve local privilege escalation. The unix_stream_sendpage() function tries to add data to the last skb in the peer's recv queue without locking the queue. Thus there is a race where unix_stream_sendpage() could access an skb locklessly that is being released by garbage collection, resulting in use-after-free. We recommend upgrading past commit 790c2f9d15b594350ae9bca7b236f2b1859de02c.
Linux Kernel could allow a local attacker to execute arbitrary code on the system, caused by a concurrency use-after-free flaw in the bad_flp_intr function. By executing a specially-crafted program, an attacker could exploit this vulnerability to execute arbitrary code or cause a denial of service condition on the system.
Access of Memory Location Before Start of Buffer in GitHub repository vim/vim prior to 8.2.
A flaw was found in the Linux kernel’s implementation of IO-URING. This flaw allows an attacker with local executable permission to create a string of requests that can cause a use-after-free flaw within the kernel. This issue leads to memory corruption and possible privilege escalation.
dmcrypt-get-device, as shipped in the eject package of Debian and Ubuntu, does not check the return value of the (1) setuid or (2) setgid function, which might cause dmcrypt-get-device to execute code, which was intended to run as an unprivileged user, as root. This affects eject through 2.1.5+deb1+cvs20081104-13.1 on Debian, eject before 2.1.5+deb1+cvs20081104-13.1ubuntu0.16.10.1 on Ubuntu 16.10, eject before 2.1.5+deb1+cvs20081104-13.1ubuntu0.16.04.1 on Ubuntu 16.04 LTS, eject before 2.1.5+deb1+cvs20081104-13.1ubuntu0.14.04.1 on Ubuntu 14.04 LTS, and eject before 2.1.5+deb1+cvs20081104-9ubuntu0.1 on Ubuntu 12.04 LTS.
Integer Overflow or Wraparound vulnerability in io_uring of Linux Kernel allows local attacker to cause memory corruption and escalate privileges to root. This issue affects: Linux Kernel versions prior to 5.4.189; version 5.4.24 and later versions.
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix race in concurrent f2fs_stop_gc_thread In my test case, concurrent calls to f2fs shutdown report the following stack trace: Oops: general protection fault, probably for non-canonical address 0xc6cfff63bb5513fc: 0000 [#1] PREEMPT SMP PTI CPU: 0 UID: 0 PID: 678 Comm: f2fs_rep_shutdo Not tainted 6.12.0-rc5-next-20241029-g6fb2fa9805c5-dirty #85 Call Trace: <TASK> ? show_regs+0x8b/0xa0 ? __die_body+0x26/0xa0 ? die_addr+0x54/0x90 ? exc_general_protection+0x24b/0x5c0 ? asm_exc_general_protection+0x26/0x30 ? kthread_stop+0x46/0x390 f2fs_stop_gc_thread+0x6c/0x110 f2fs_do_shutdown+0x309/0x3a0 f2fs_ioc_shutdown+0x150/0x1c0 __f2fs_ioctl+0xffd/0x2ac0 f2fs_ioctl+0x76/0xe0 vfs_ioctl+0x23/0x60 __x64_sys_ioctl+0xce/0xf0 x64_sys_call+0x2b1b/0x4540 do_syscall_64+0xa7/0x240 entry_SYSCALL_64_after_hwframe+0x76/0x7e The root cause is a race condition in f2fs_stop_gc_thread() called from different f2fs shutdown paths: [CPU0] [CPU1] ---------------------- ----------------------- f2fs_stop_gc_thread f2fs_stop_gc_thread gc_th = sbi->gc_thread gc_th = sbi->gc_thread kfree(gc_th) sbi->gc_thread = NULL < gc_th != NULL > kthread_stop(gc_th->f2fs_gc_task) //UAF The commit c7f114d864ac ("f2fs: fix to avoid use-after-free in f2fs_stop_gc_thread()") attempted to fix this issue by using a read semaphore to prevent races between shutdown and remount threads, but it fails to prevent all race conditions. Fix it by converting to write lock of s_umount in f2fs_do_shutdown().
A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe and push_pipe functions in the Linux kernel and could thus contain stale values. An unprivileged local user could use this flaw to write to pages in the page cache backed by read only files and as such escalate their privileges on the system.
In the Linux kernel, the following vulnerability has been resolved: mm, slub: fix potential use-after-free in slab_debugfs_fops When sysfs_slab_add failed, we shouldn't call debugfs_slab_add() for s because s will be freed soon. And slab_debugfs_fops will use s later leading to a use-after-free.
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix UAF by grabbing blkcg lock before destroying blkg pd KASAN reports a use-after-free report when doing fuzz test: [693354.104835] ================================================================== [693354.105094] BUG: KASAN: use-after-free in bfq_io_set_weight_legacy+0xd3/0x160 [693354.105336] Read of size 4 at addr ffff888be0a35664 by task sh/1453338 [693354.105607] CPU: 41 PID: 1453338 Comm: sh Kdump: loaded Not tainted 4.18.0-147 [693354.105610] Hardware name: Huawei 2288H V5/BC11SPSCB0, BIOS 0.81 07/02/2018 [693354.105612] Call Trace: [693354.105621] dump_stack+0xf1/0x19b [693354.105626] ? show_regs_print_info+0x5/0x5 [693354.105634] ? printk+0x9c/0xc3 [693354.105638] ? cpumask_weight+0x1f/0x1f [693354.105648] print_address_description+0x70/0x360 [693354.105654] kasan_report+0x1b2/0x330 [693354.105659] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105665] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105670] bfq_io_set_weight_legacy+0xd3/0x160 [693354.105675] ? bfq_cpd_init+0x20/0x20 [693354.105683] cgroup_file_write+0x3aa/0x510 [693354.105693] ? ___slab_alloc+0x507/0x540 [693354.105698] ? cgroup_file_poll+0x60/0x60 [693354.105702] ? 0xffffffff89600000 [693354.105708] ? usercopy_abort+0x90/0x90 [693354.105716] ? mutex_lock+0xef/0x180 [693354.105726] kernfs_fop_write+0x1ab/0x280 [693354.105732] ? cgroup_file_poll+0x60/0x60 [693354.105738] vfs_write+0xe7/0x230 [693354.105744] ksys_write+0xb0/0x140 [693354.105749] ? __ia32_sys_read+0x50/0x50 [693354.105760] do_syscall_64+0x112/0x370 [693354.105766] ? syscall_return_slowpath+0x260/0x260 [693354.105772] ? do_page_fault+0x9b/0x270 [693354.105779] ? prepare_exit_to_usermode+0xf9/0x1a0 [693354.105784] ? enter_from_user_mode+0x30/0x30 [693354.105793] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.105875] Allocated by task 1453337: [693354.106001] kasan_kmalloc+0xa0/0xd0 [693354.106006] kmem_cache_alloc_node_trace+0x108/0x220 [693354.106010] bfq_pd_alloc+0x96/0x120 [693354.106015] blkcg_activate_policy+0x1b7/0x2b0 [693354.106020] bfq_create_group_hierarchy+0x1e/0x80 [693354.106026] bfq_init_queue+0x678/0x8c0 [693354.106031] blk_mq_init_sched+0x1f8/0x460 [693354.106037] elevator_switch_mq+0xe1/0x240 [693354.106041] elevator_switch+0x25/0x40 [693354.106045] elv_iosched_store+0x1a1/0x230 [693354.106049] queue_attr_store+0x78/0xb0 [693354.106053] kernfs_fop_write+0x1ab/0x280 [693354.106056] vfs_write+0xe7/0x230 [693354.106060] ksys_write+0xb0/0x140 [693354.106064] do_syscall_64+0x112/0x370 [693354.106069] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106114] Freed by task 1453336: [693354.106225] __kasan_slab_free+0x130/0x180 [693354.106229] kfree+0x90/0x1b0 [693354.106233] blkcg_deactivate_policy+0x12c/0x220 [693354.106238] bfq_exit_queue+0xf5/0x110 [693354.106241] blk_mq_exit_sched+0x104/0x130 [693354.106245] __elevator_exit+0x45/0x60 [693354.106249] elevator_switch_mq+0xd6/0x240 [693354.106253] elevator_switch+0x25/0x40 [693354.106257] elv_iosched_store+0x1a1/0x230 [693354.106261] queue_attr_store+0x78/0xb0 [693354.106264] kernfs_fop_write+0x1ab/0x280 [693354.106268] vfs_write+0xe7/0x230 [693354.106271] ksys_write+0xb0/0x140 [693354.106275] do_syscall_64+0x112/0x370 [693354.106280] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106329] The buggy address belongs to the object at ffff888be0a35580 which belongs to the cache kmalloc-1k of size 1024 [693354.106736] The buggy address is located 228 bytes inside of 1024-byte region [ffff888be0a35580, ffff888be0a35980) [693354.107114] The buggy address belongs to the page: [693354.107273] page:ffffea002f828c00 count:1 mapcount:0 mapping:ffff888107c17080 index:0x0 compound_mapcount: 0 [693354.107606] flags: 0x17ffffc0008100(slab|head) [693354.107760] raw: 0017ffffc0008100 ffffea002fcbc808 ffffea0030bd3a08 ffff888107c17080 [693354.108020] r ---truncated---
In the Linux kernel, the following vulnerability has been resolved: i2c: virtio: disable timeout handling If a timeout is hit, it can result is incorrect data on the I2C bus and/or memory corruptions in the guest since the device can still be operating on the buffers it was given while the guest has freed them. Here is, for example, the start of a slub_debug splat which was triggered on the next transfer after one transfer was forced to timeout by setting a breakpoint in the backend (rust-vmm/vhost-device): BUG kmalloc-1k (Not tainted): Poison overwritten First byte 0x1 instead of 0x6b Allocated in virtio_i2c_xfer+0x65/0x35c age=350 cpu=0 pid=29 __kmalloc+0xc2/0x1c9 virtio_i2c_xfer+0x65/0x35c __i2c_transfer+0x429/0x57d i2c_transfer+0x115/0x134 i2cdev_ioctl_rdwr+0x16a/0x1de i2cdev_ioctl+0x247/0x2ed vfs_ioctl+0x21/0x30 sys_ioctl+0xb18/0xb41 Freed in virtio_i2c_xfer+0x32e/0x35c age=244 cpu=0 pid=29 kfree+0x1bd/0x1cc virtio_i2c_xfer+0x32e/0x35c __i2c_transfer+0x429/0x57d i2c_transfer+0x115/0x134 i2cdev_ioctl_rdwr+0x16a/0x1de i2cdev_ioctl+0x247/0x2ed vfs_ioctl+0x21/0x30 sys_ioctl+0xb18/0xb41 There is no simple fix for this (the driver would have to always create bounce buffers and hold on to them until the device eventually returns the buffers), so just disable the timeout support for now.
In the Linux kernel, the following vulnerability has been resolved: mac80211: fix use-after-free in CCMP/GCMP RX When PN checking is done in mac80211, for fragmentation we need to copy the PN to the RX struct so we can later use it to do a comparison, since commit bf30ca922a0c ("mac80211: check defrag PN against current frame"). Unfortunately, in that commit I used the 'hdr' variable without it being necessarily valid, so use-after-free could occur if it was necessary to reallocate (parts of) the frame. Fix this by reloading the variable after the code that results in the reallocations, if any. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=214401.
In the Linux kernel, the following vulnerability has been resolved: dm btree remove: fix use after free in rebalance_children() Move dm_tm_unlock() after dm_tm_dec().
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: unlink table before deleting it syzbot reports following UAF: BUG: KASAN: use-after-free in memcmp+0x18f/0x1c0 lib/string.c:955 nla_strcmp+0xf2/0x130 lib/nlattr.c:836 nft_table_lookup.part.0+0x1a2/0x460 net/netfilter/nf_tables_api.c:570 nft_table_lookup net/netfilter/nf_tables_api.c:4064 [inline] nf_tables_getset+0x1b3/0x860 net/netfilter/nf_tables_api.c:4064 nfnetlink_rcv_msg+0x659/0x13f0 net/netfilter/nfnetlink.c:285 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 Problem is that all get operations are lockless, so the commit_mutex held by nft_rcv_nl_event() isn't enough to stop a parallel GET request from doing read-accesses to the table object even after synchronize_rcu(). To avoid this, unlink the table first and store the table objects in on-stack scratch space.
In the Linux kernel, the following vulnerability has been resolved: can: dev: can_restart: fix use after free bug After calling netif_rx_ni(skb), dereferencing skb is unsafe. Especially, the can_frame cf which aliases skb memory is accessed after the netif_rx_ni() in: stats->rx_bytes += cf->len; Reordering the lines solves the issue.