In the Linux kernel, the following vulnerability has been resolved: block/ioctl: prefer different overflow check Running syzkaller with the newly reintroduced signed integer overflow sanitizer shows this report: [ 62.982337] ------------[ cut here ]------------ [ 62.985692] cgroup: Invalid name [ 62.986211] UBSAN: signed-integer-overflow in ../block/ioctl.c:36:46 [ 62.989370] 9pnet_fd: p9_fd_create_tcp (7343): problem connecting socket to 127.0.0.1 [ 62.992992] 9223372036854775807 + 4095 cannot be represented in type 'long long' [ 62.997827] 9pnet_fd: p9_fd_create_tcp (7345): problem connecting socket to 127.0.0.1 [ 62.999369] random: crng reseeded on system resumption [ 63.000634] GUP no longer grows the stack in syz-executor.2 (7353): 20002000-20003000 (20001000) [ 63.000668] CPU: 0 PID: 7353 Comm: syz-executor.2 Not tainted 6.8.0-rc2-00035-gb3ef86b5a957 #1 [ 63.000677] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 63.000682] Call Trace: [ 63.000686] <TASK> [ 63.000731] dump_stack_lvl+0x93/0xd0 [ 63.000919] __get_user_pages+0x903/0xd30 [ 63.001030] __gup_longterm_locked+0x153e/0x1ba0 [ 63.001041] ? _raw_read_unlock_irqrestore+0x17/0x50 [ 63.001072] ? try_get_folio+0x29c/0x2d0 [ 63.001083] internal_get_user_pages_fast+0x1119/0x1530 [ 63.001109] iov_iter_extract_pages+0x23b/0x580 [ 63.001206] bio_iov_iter_get_pages+0x4de/0x1220 [ 63.001235] iomap_dio_bio_iter+0x9b6/0x1410 [ 63.001297] __iomap_dio_rw+0xab4/0x1810 [ 63.001316] iomap_dio_rw+0x45/0xa0 [ 63.001328] ext4_file_write_iter+0xdde/0x1390 [ 63.001372] vfs_write+0x599/0xbd0 [ 63.001394] ksys_write+0xc8/0x190 [ 63.001403] do_syscall_64+0xd4/0x1b0 [ 63.001421] ? arch_exit_to_user_mode_prepare+0x3a/0x60 [ 63.001479] entry_SYSCALL_64_after_hwframe+0x6f/0x77 [ 63.001535] RIP: 0033:0x7f7fd3ebf539 [ 63.001551] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 [ 63.001562] RSP: 002b:00007f7fd32570c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 63.001584] RAX: ffffffffffffffda RBX: 00007f7fd3ff3f80 RCX: 00007f7fd3ebf539 [ 63.001590] RDX: 4db6d1e4f7e43360 RSI: 0000000020000000 RDI: 0000000000000004 [ 63.001595] RBP: 00007f7fd3f1e496 R08: 0000000000000000 R09: 0000000000000000 [ 63.001599] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 63.001604] R13: 0000000000000006 R14: 00007f7fd3ff3f80 R15: 00007ffd415ad2b8 ... [ 63.018142] ---[ end trace ]--- Historically, the signed integer overflow sanitizer did not work in the kernel due to its interaction with `-fwrapv` but this has since been changed [1] in the newest version of Clang; It was re-enabled in the kernel with Commit 557f8c582a9ba8ab ("ubsan: Reintroduce signed overflow sanitizer"). Let's rework this overflow checking logic to not actually perform an overflow during the check itself, thus avoiding the UBSAN splat. [1]: https://github.com/llvm/llvm-project/pull/82432

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.

kernel/bpf/verifier.c in the Linux kernel through 5.15.14 allows local users to gain privileges because of the availability of pointer arithmetic via certain *_OR_NULL pointer types.

In the Linux kernel 6.0.8, there is a use-after-free in inode_cgwb_move_to_attached in fs/fs-writeback.c, related to __list_del_entry_valid.

IBM DB2 for Linux, UNIX and Windows 9.7, 10,1, 10.5, and 11.1 (includes DB2 Connect Server) could allow a local user with DB2 instance owner privileges to obtain root access. IBM X-Force ID: 128058.

In the Linux kernel 6.0.8, there is a use-after-free in run_unpack in fs/ntfs3/run.c, related to a difference between NTFS sector size and media sector size.

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.

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.

Integer overflow in the ethtool_get_rxnfc function in net/core/ethtool.c in the Linux kernel before 2.6.33.7 on 32-bit platforms allows local users to cause a denial of service or possibly have unspecified other impact via an ETHTOOL_GRXCLSRLALL ethtool command with a large info.rule_cnt value that triggers a buffer overflow, a different vulnerability than CVE-2010-3084.

In the Linux kernel, the following vulnerability has been resolved: ima: Fix use-after-free on a dentry's dname.name ->d_name.name can change on rename and the earlier value can be freed; there are conditions sufficient to stabilize it (->d_lock on dentry, ->d_lock on its parent, ->i_rwsem exclusive on the parent's inode, rename_lock), but none of those are met at any of the sites. Take a stable snapshot of the name instead.

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 do_anonymous_page function in mm/memory.c in the Linux kernel before 2.6.27.52, 2.6.32.x before 2.6.32.19, 2.6.34.x before 2.6.34.4, and 2.6.35.x before 2.6.35.2 does not properly separate the stack and the heap, which allows context-dependent attackers to execute arbitrary code by writing to the bottom page of a shared memory segment, as demonstrated by a memory-exhaustion attack against the X.Org X server.

afu_mmio_region_get_by_offset in drivers/fpga/dfl-afu-region.c in the Linux kernel through 6.1.12 has an integer overflow.

In the Linux kernel, the following vulnerability has been resolved: drivers/perf: hisi_pcie: Fix out-of-bound access when valid event group The perf tool allows users to create event groups through following cmd [1], but the driver does not check whether the array index is out of bounds when writing data to the event_group array. If the number of events in an event_group is greater than HISI_PCIE_MAX_COUNTERS, the memory write overflow of event_group array occurs. Add array index check to fix the possible array out of bounds violation, and return directly when write new events are written to array bounds. There are 9 different events in an event_group. [1] perf stat -e '{pmu/event1/, ... ,pmu/event9/}'

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix use-after-free of timer for log writer thread Patch series "nilfs2: fix log writer related issues". This bug fix series covers three nilfs2 log writer-related issues, including a timer use-after-free issue and potential deadlock issue on unmount, and a potential freeze issue in event synchronization found during their analysis. Details are described in each commit log. This patch (of 3): A use-after-free issue has been reported regarding the timer sc_timer on the nilfs_sc_info structure. The problem is that even though it is used to wake up a sleeping log writer thread, sc_timer is not shut down until the nilfs_sc_info structure is about to be freed, and is used regardless of the thread's lifetime. Fix this issue by limiting the use of sc_timer only while the log writer thread is alive.

The release_one_tty function in drivers/char/tty_io.c in the Linux kernel before 2.6.34-rc4 omits certain required calls to the put_pid function, which has unspecified impact and local attack vectors.

Director Agent 6.1 before 6.1.2.3 in IBM Systems Director on AIX and Linux uses incorrect permissions for the (1) diruninstall and (2) opt/ibm/director/bin/wcitinst scripts, which allows local users to gain privileges by executing these scripts.

Format string vulnerability in vmrun in VMware VIX API 1.6.x, VMware Workstation 6.5.x before 6.5.4 build 246459, VMware Player 2.5.x before 2.5.4 build 246459, and VMware Server 2.x on Linux, and VMware Fusion 2.x before 2.0.7 build 246742, allows local users to gain privileges via format string specifiers in process metadata.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/mes: fix use-after-free issue Delete fence fallback timer to fix the ramdom use-after-free issue. v2: move to amdgpu_mes.c

A flaw was found in the fixed buffer registration code for io_uring (io_sqe_buffer_register in io_uring/rsrc.c) in the Linux kernel that allows out-of-bounds access to physical memory beyond the end of the buffer. This flaw enables full local privilege escalation.

In the Linux kernel, the following vulnerability has been resolved: gfs2: Fix potential glock use-after-free on unmount When a DLM lockspace is released and there ares still locks in that lockspace, DLM will unlock those locks automatically. Commit fb6791d100d1b started exploiting this behavior to speed up filesystem unmount: gfs2 would simply free glocks it didn't want to unlock and then release the lockspace. This didn't take the bast callbacks for asynchronous lock contention notifications into account, which remain active until until a lock is unlocked or its lockspace is released. To prevent those callbacks from accessing deallocated objects, put the glocks that should not be unlocked on the sd_dead_glocks list, release the lockspace, and only then free those glocks. As an additional measure, ignore unexpected ast and bast callbacks if the receiving glock is dead.

A vulnerability in the ClearPass OnGuard Linux agent could allow malicious users on a Linux instance to elevate their user privileges to those of a higher role. A successful exploit allows malicious users to execute arbitrary code with root level privileges on the Linux instance.

In the Linux kernel, the following vulnerability has been resolved: drm: zynqmp_dpsub: Always register bridge We must always register the DRM bridge, since zynqmp_dp_hpd_work_func calls drm_bridge_hpd_notify, which in turn expects hpd_mutex to be initialized. We do this before zynqmp_dpsub_drm_init since that calls drm_bridge_attach. This fixes the following lockdep warning: [ 19.217084] ------------[ cut here ]------------ [ 19.227530] DEBUG_LOCKS_WARN_ON(lock->magic != lock) [ 19.227768] WARNING: CPU: 0 PID: 140 at kernel/locking/mutex.c:582 __mutex_lock+0x4bc/0x550 [ 19.241696] Modules linked in: [ 19.244937] CPU: 0 PID: 140 Comm: kworker/0:4 Not tainted 6.6.20+ #96 [ 19.252046] Hardware name: xlnx,zynqmp (DT) [ 19.256421] Workqueue: events zynqmp_dp_hpd_work_func [ 19.261795] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 19.269104] pc : __mutex_lock+0x4bc/0x550 [ 19.273364] lr : __mutex_lock+0x4bc/0x550 [ 19.277592] sp : ffffffc085c5bbe0 [ 19.281066] x29: ffffffc085c5bbe0 x28: 0000000000000000 x27: ffffff88009417f8 [ 19.288624] x26: ffffff8800941788 x25: ffffff8800020008 x24: ffffffc082aa3000 [ 19.296227] x23: ffffffc080d90e3c x22: 0000000000000002 x21: 0000000000000000 [ 19.303744] x20: 0000000000000000 x19: ffffff88002f5210 x18: 0000000000000000 [ 19.311295] x17: 6c707369642e3030 x16: 3030613464662072 x15: 0720072007200720 [ 19.318922] x14: 0000000000000000 x13: 284e4f5f4e524157 x12: 0000000000000001 [ 19.326442] x11: 0001ffc085c5b940 x10: 0001ff88003f388b x9 : 0001ff88003f3888 [ 19.334003] x8 : 0001ff88003f3888 x7 : 0000000000000000 x6 : 0000000000000000 [ 19.341537] x5 : 0000000000000000 x4 : 0000000000001668 x3 : 0000000000000000 [ 19.349054] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffffff88003f3880 [ 19.356581] Call trace: [ 19.359160] __mutex_lock+0x4bc/0x550 [ 19.363032] mutex_lock_nested+0x24/0x30 [ 19.367187] drm_bridge_hpd_notify+0x2c/0x6c [ 19.371698] zynqmp_dp_hpd_work_func+0x44/0x54 [ 19.376364] process_one_work+0x3ac/0x988 [ 19.380660] worker_thread+0x398/0x694 [ 19.384736] kthread+0x1bc/0x1c0 [ 19.388241] ret_from_fork+0x10/0x20 [ 19.392031] irq event stamp: 183 [ 19.395450] hardirqs last enabled at (183): [<ffffffc0800b9278>] finish_task_switch.isra.0+0xa8/0x2d4 [ 19.405140] hardirqs last disabled at (182): [<ffffffc081ad3754>] __schedule+0x714/0xd04 [ 19.413612] softirqs last enabled at (114): [<ffffffc080133de8>] srcu_invoke_callbacks+0x158/0x23c [ 19.423128] softirqs last disabled at (110): [<ffffffc080133de8>] srcu_invoke_callbacks+0x158/0x23c [ 19.432614] ---[ end trace 0000000000000000 ]--- (cherry picked from commit 61ba791c4a7a09a370c45b70a81b8c7d4cf6b2ae)

In the Linux kernel, the following vulnerability has been resolved: riscv: prevent pt_regs corruption for secondary idle threads Top of the kernel thread stack should be reserved for pt_regs. However this is not the case for the idle threads of the secondary boot harts. Their stacks overlap with their pt_regs, so both may get corrupted. Similar issue has been fixed for the primary hart, see c7cdd96eca28 ("riscv: prevent stack corruption by reserving task_pt_regs(p) early"). However that fix was not propagated to the secondary harts. The problem has been noticed in some CPU hotplug tests with V enabled. The function smp_callin stored several registers on stack, corrupting top of pt_regs structure including status field. As a result, kernel attempted to save or restore inexistent V context.

Buffer overflow in the auerswald_probe function in the Auerswald Linux USB driver for the Linux kernel before 2.6.27 allows physically proximate attackers to execute arbitrary code, cause a denial of service via a crafted USB device, or take full control of the system.

Linux kernel before 2.6.22.17, when using certain drivers that register a fault handler that does not perform range checks, allows local users to access kernel memory via an out-of-range offset.

Unspecified vulnerability in the VBoxNetAdpCtl configuration tool in Sun VirtualBox 3.0.x before 3.0.8 on Solaris x86, Linux, and Mac OS X allows local users to gain privileges via unknown vectors.

In the Linux kernel, the following vulnerability has been resolved: af_unix: Don't return OOB skb in manage_oob(). syzbot reported use-after-free in unix_stream_recv_urg(). [0] The scenario is 1. send(MSG_OOB) 2. recv(MSG_OOB) -> The consumed OOB remains in recv queue 3. send(MSG_OOB) 4. recv() -> manage_oob() returns the next skb of the consumed OOB -> This is also OOB, but unix_sk(sk)->oob_skb is not cleared 5. recv(MSG_OOB) -> unix_sk(sk)->oob_skb is used but already freed The recent commit 8594d9b85c07 ("af_unix: Don't call skb_get() for OOB skb.") uncovered the issue. If the OOB skb is consumed and the next skb is peeked in manage_oob(), we still need to check if the skb is OOB. Let's do so by falling back to the following checks in manage_oob() and add the test case in selftest. Note that we need to add a similar check for SIOCATMARK. [0]: BUG: KASAN: slab-use-after-free in unix_stream_read_actor+0xa6/0xb0 net/unix/af_unix.c:2959 Read of size 4 at addr ffff8880326abcc4 by task syz-executor178/5235 CPU: 0 UID: 0 PID: 5235 Comm: syz-executor178 Not tainted 6.11.0-rc5-syzkaller-00742-gfbdaffe41adc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 unix_stream_read_actor+0xa6/0xb0 net/unix/af_unix.c:2959 unix_stream_recv_urg+0x1df/0x320 net/unix/af_unix.c:2640 unix_stream_read_generic+0x2456/0x2520 net/unix/af_unix.c:2778 unix_stream_recvmsg+0x22b/0x2c0 net/unix/af_unix.c:2996 sock_recvmsg_nosec net/socket.c:1046 [inline] sock_recvmsg+0x22f/0x280 net/socket.c:1068 ____sys_recvmsg+0x1db/0x470 net/socket.c:2816 ___sys_recvmsg net/socket.c:2858 [inline] __sys_recvmsg+0x2f0/0x3e0 net/socket.c:2888 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5360d6b4e9 Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff29b3a458 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 00007fff29b3a638 RCX: 00007f5360d6b4e9 RDX: 0000000000002001 RSI: 0000000020000640 RDI: 0000000000000003 RBP: 00007f5360dde610 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff29b3a628 R14: 0000000000000001 R15: 0000000000000001 </TASK> Allocated by task 5235: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4080 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:667 alloc_skb include/linux/skbuff.h:1320 [inline] alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6528 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2815 sock_alloc_send_skb include/net/sock.h:1778 [inline] queue_oob+0x108/0x680 net/unix/af_unix.c:2198 unix_stream_sendmsg+0xd24/0xf80 net/unix/af_unix.c:2351 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597 ___sys_sendmsg net/socket.c:2651 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5235: kasan_save_stack mm/kasan/common.c:47 ---truncated---

Use-after-free vulnerability in the fasync_helper function in fs/fcntl.c in the Linux kernel before 2.6.33-rc4-git1 allows local users to gain privileges via vectors that include enabling O_ASYNC (aka FASYNC or FIOASYNC) on a locked file, and then closing this file.

The EXT4_IOC_MOVE_EXT (aka move extents) ioctl implementation in the ext4 filesystem in the Linux kernel before 2.6.32-git6 allows local users to overwrite arbitrary files via a crafted request, related to insufficient checks for file permissions.

The connector layer in the Linux kernel before 2.6.31.5 does not require the CAP_SYS_ADMIN capability for certain interaction with the (1) uvesafb, (2) pohmelfs, (3) dst, or (4) dm subsystem, which allows local users to bypass intended access restrictions and gain privileges via calls to functions in these subsystems.

In the Linux kernel, the following vulnerability has been resolved: platform/x86: toshiba_acpi: Fix array out-of-bounds access In order to use toshiba_dmi_quirks[] together with the standard DMI matching functions, it must be terminated by a empty entry. Since this entry is missing, an array out-of-bounds access occurs every time the quirk list is processed. Fix this by adding the terminating empty entry.

Array index error in the gdth_read_event function in drivers/scsi/gdth.c in the Linux kernel before 2.6.32-rc8 allows local users to cause a denial of service or possibly gain privileges via a negative event index in an IOCTL request.

Integer overflow in the kvm_dev_ioctl_get_supported_cpuid function in arch/x86/kvm/x86.c in the KVM subsystem in the Linux kernel before 2.6.31.4 allows local users to have an unspecified impact via a KVM_GET_SUPPORTED_CPUID request to the kvm_arch_dev_ioctl function.

The udp_sendmsg function in the UDP implementation in (1) net/ipv4/udp.c and (2) net/ipv6/udp.c in the Linux kernel before 2.6.19 allows local users to gain privileges or cause a denial of service (NULL pointer dereference and system crash) via vectors involving the MSG_MORE flag and a UDP socket.

Signal Desktop before 6.2.0 on Windows, Linux, and macOS allows an attacker to modify conversation attachments within the attachments.noindex directory. Client mechanisms fail to validate modifications of existing cached files, resulting in an attacker's ability to insert malicious code into pre-existing attachments or replace them completely. A threat actor can forward the existing attachment in the corresponding conversation to external groups, and the name and size of the file will not change, allowing the malware to masquerade as another file. NOTE: the vendor disputes the relevance of this finding because the product is not intended to protect against adversaries with this degree of local access.

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential UAF in smb2_is_valid_lease_break() Skip sessions that are being teared down (status == SES_EXITING) to avoid UAF.

In the Linux kernel, the following vulnerability has been resolved: ax25: fix use-after-free bugs caused by ax25_ds_del_timer When the ax25 device is detaching, the ax25_dev_device_down() calls ax25_ds_del_timer() to cleanup the slave_timer. When the timer handler is running, the ax25_ds_del_timer() that calls del_timer() in it will return directly. As a result, the use-after-free bugs could happen, one of the scenarios is shown below: (Thread 1) | (Thread 2) | ax25_ds_timeout() ax25_dev_device_down() | ax25_ds_del_timer() | del_timer() | ax25_dev_put() //FREE | | ax25_dev-> //USE In order to mitigate bugs, when the device is detaching, use timer_shutdown_sync() to stop the timer.

In the Linux kernel, the following vulnerability has been resolved: rcu/nocb: Fix WARN_ON_ONCE() in the rcu_nocb_bypass_lock() For the kernels built with CONFIG_RCU_NOCB_CPU_DEFAULT_ALL=y and CONFIG_RCU_LAZY=y, the following scenarios will trigger WARN_ON_ONCE() in the rcu_nocb_bypass_lock() and rcu_nocb_wait_contended() functions: CPU2 CPU11 kthread rcu_nocb_cb_kthread ksys_write rcu_do_batch vfs_write rcu_torture_timer_cb proc_sys_write __kmem_cache_free proc_sys_call_handler kmemleak_free drop_caches_sysctl_handler delete_object_full drop_slab __delete_object shrink_slab put_object lazy_rcu_shrink_scan call_rcu rcu_nocb_flush_bypass __call_rcu_commn rcu_nocb_bypass_lock raw_spin_trylock(&rdp->nocb_bypass_lock) fail atomic_inc(&rdp->nocb_lock_contended); rcu_nocb_wait_contended WARN_ON_ONCE(smp_processor_id() != rdp->cpu); WARN_ON_ONCE(atomic_read(&rdp->nocb_lock_contended)) | |_ _ _ _ _ _ _ _ _ _same rdp and rdp->cpu != 11_ _ _ _ _ _ _ _ _ __| Reproduce this bug with "echo 3 > /proc/sys/vm/drop_caches". This commit therefore uses rcu_nocb_try_flush_bypass() instead of rcu_nocb_flush_bypass() in lazy_rcu_shrink_scan(). If the nocb_bypass queue is being flushed, then rcu_nocb_try_flush_bypass will return directly.

The Linux kernel 2.6.0 through 2.6.30.4, and 2.4.4 through 2.4.37.4, does not initialize all function pointers for socket operations in proto_ops structures, which allows local users to trigger a NULL pointer dereference and gain privileges by using mmap to map page zero, placing arbitrary code on this page, and then invoking an unavailable operation, as demonstrated by the sendpage operation (sock_sendpage function) on a PF_PPPOX socket.

The cookie feature in the packet action API implementation in net/sched/act_api.c in the Linux kernel 4.11.x through 4.11-rc7 mishandles the tb nlattr array, which allows local users to cause a denial of service (uninitialized memory access and refcount underflow, and system hang or crash) or possibly have unspecified other impact via "tc filter add" commands in certain contexts. NOTE: this does not affect stable kernels, such as 4.10.x, from kernel.org.

In rndis_query_oid in drivers/net/wireless/rndis_wlan.c in the Linux kernel through 6.1.5, there is an integer overflow in an addition.

The load_flat_shared_library function in fs/binfmt_flat.c in the flat subsystem in the Linux kernel before 2.6.31-rc6 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by executing a shared flat binary, which triggers an access of an "uninitialized cred pointer."

The ATI Rage 128 (aka r128) driver in the Linux kernel before 2.6.31-git11 does not properly verify Concurrent Command Engine (CCE) state initialization, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly gain privileges via unspecified ioctl calls.

In the Linux kernel, the following vulnerability has been resolved: raid1: fix use-after-free for original bio in raid1_write_request() r1_bio->bios[] is used to record new bios that will be issued to underlying disks, however, in raid1_write_request(), r1_bio->bios[] will set to the original bio temporarily. Meanwhile, if blocked rdev is set, free_r1bio() will be called causing that all r1_bio->bios[] to be freed: raid1_write_request() r1_bio = alloc_r1bio(mddev, bio); -> r1_bio->bios[] is NULL for (i = 0; i < disks; i++) -> for each rdev in conf // first rdev is normal r1_bio->bios[0] = bio; -> set to original bio // second rdev is blocked if (test_bit(Blocked, &rdev->flags)) break if (blocked_rdev) free_r1bio() put_all_bios() bio_put(r1_bio->bios[0]) -> original bio is freed Test scripts: mdadm -CR /dev/md0 -l1 -n4 /dev/sd[abcd] --assume-clean fio -filename=/dev/md0 -ioengine=libaio -rw=write -bs=4k -numjobs=1 \ -iodepth=128 -name=test -direct=1 echo blocked > /sys/block/md0/md/rd2/state Test result: BUG bio-264 (Not tainted): Object already free ----------------------------------------------------------------------------- Allocated in mempool_alloc_slab+0x24/0x50 age=1 cpu=1 pid=869 kmem_cache_alloc+0x324/0x480 mempool_alloc_slab+0x24/0x50 mempool_alloc+0x6e/0x220 bio_alloc_bioset+0x1af/0x4d0 blkdev_direct_IO+0x164/0x8a0 blkdev_write_iter+0x309/0x440 aio_write+0x139/0x2f0 io_submit_one+0x5ca/0xb70 __do_sys_io_submit+0x86/0x270 __x64_sys_io_submit+0x22/0x30 do_syscall_64+0xb1/0x210 entry_SYSCALL_64_after_hwframe+0x6c/0x74 Freed in mempool_free_slab+0x1f/0x30 age=1 cpu=1 pid=869 kmem_cache_free+0x28c/0x550 mempool_free_slab+0x1f/0x30 mempool_free+0x40/0x100 bio_free+0x59/0x80 bio_put+0xf0/0x220 free_r1bio+0x74/0xb0 raid1_make_request+0xadf/0x1150 md_handle_request+0xc7/0x3b0 md_submit_bio+0x76/0x130 __submit_bio+0xd8/0x1d0 submit_bio_noacct_nocheck+0x1eb/0x5c0 submit_bio_noacct+0x169/0xd40 submit_bio+0xee/0x1d0 blkdev_direct_IO+0x322/0x8a0 blkdev_write_iter+0x309/0x440 aio_write+0x139/0x2f0 Since that bios for underlying disks are not allocated yet, fix this problem by using mempool_free() directly to free the r1_bio.

In the Linux kernel, the following vulnerability has been resolved: media: mediatek: vcodec: Fix oops when HEVC init fails The stateless HEVC decoder saves the instance pointer in the context regardless if the initialization worked or not. This caused a use after free, when the pointer is freed in case of a failure in the deinit function. Only store the instance pointer when the initialization was successful, to solve this issue. Hardware name: Acer Tomato (rev3 - 4) board (DT) pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : vcodec_vpu_send_msg+0x4c/0x190 [mtk_vcodec_dec] lr : vcodec_send_ap_ipi+0x78/0x170 [mtk_vcodec_dec] sp : ffff80008750bc20 x29: ffff80008750bc20 x28: ffff1299f6d70000 x27: 0000000000000000 x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 x23: ffff80008750bc98 x22: 000000000000a003 x21: ffffd45c4cfae000 x20: 0000000000000010 x19: ffff1299fd668310 x18: 000000000000001a x17: 000000040044ffff x16: ffffd45cb15dc648 x15: 0000000000000000 x14: ffff1299c08da1c0 x13: ffffd45cb1f87a10 x12: ffffd45cb2f5fe80 x11: 0000000000000001 x10: 0000000000001b30 x9 : ffffd45c4d12b488 x8 : 1fffe25339380d81 x7 : 0000000000000001 x6 : ffff1299c9c06c00 x5 : 0000000000000132 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000010 x1 : ffff80008750bc98 x0 : 0000000000000000 Call trace: vcodec_vpu_send_msg+0x4c/0x190 [mtk_vcodec_dec] vcodec_send_ap_ipi+0x78/0x170 [mtk_vcodec_dec] vpu_dec_deinit+0x1c/0x30 [mtk_vcodec_dec] vdec_hevc_slice_deinit+0x30/0x98 [mtk_vcodec_dec] vdec_if_deinit+0x38/0x68 [mtk_vcodec_dec] mtk_vcodec_dec_release+0x20/0x40 [mtk_vcodec_dec] fops_vcodec_release+0x64/0x118 [mtk_vcodec_dec] v4l2_release+0x7c/0x100 __fput+0x80/0x2d8 __fput_sync+0x58/0x70 __arm64_sys_close+0x40/0x90 invoke_syscall+0x50/0x128 el0_svc_common.constprop.0+0x48/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x38/0xd8 el0t_64_sync_handler+0xc0/0xc8 el0t_64_sync+0x1a8/0x1b0 Code: d503201f f9401660 b900127f b900227f (f9400400)

A use-after-free vulnerability in the Linux Kernel io_uring subsystem can be exploited to achieve local privilege escalation. Both io_install_fixed_file and its callers call fput in a file in case of an error, causing a reference underflow which leads to a use-after-free vulnerability. We recommend upgrading past commit 9d94c04c0db024922e886c9fd429659f22f48ea4.

The kvm_emulate_hypercall function in arch/x86/kvm/x86.c in KVM in the Linux kernel 2.6.25-rc1, and other versions before 2.6.31, when running on x86 systems, does not prevent access to MMU hypercalls from ring 0, which allows local guest OS users to cause a denial of service (guest kernel crash) and read or write guest kernel memory via unspecified "random addresses."

A vulnerability was found in compare_netdev_and_ip in drivers/infiniband/core/cma.c in RDMA in the Linux Kernel. The improper cleanup results in out-of-boundary read, where a local user can utilize this problem to crash the system or escalation of privilege.