In the Linux kernel, the following vulnerability has been resolved: ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up The issue was caused by dput(upper) being called before ovl_dentry_update_reval(), while upper->d_flags was still accessed in ovl_dentry_remote(). Move dput(upper) after its last use to prevent use-after-free. BUG: KASAN: slab-use-after-free in ovl_dentry_remote fs/overlayfs/util.c:162 [inline] BUG: KASAN: slab-use-after-free in ovl_dentry_update_reval+0xd2/0xf0 fs/overlayfs/util.c:167 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 ovl_dentry_remote fs/overlayfs/util.c:162 [inline] ovl_dentry_update_reval+0xd2/0xf0 fs/overlayfs/util.c:167 ovl_link_up fs/overlayfs/copy_up.c:610 [inline] ovl_copy_up_one+0x2105/0x3490 fs/overlayfs/copy_up.c:1170 ovl_copy_up_flags+0x18d/0x200 fs/overlayfs/copy_up.c:1223 ovl_rename+0x39e/0x18c0 fs/overlayfs/dir.c:1136 vfs_rename+0xf84/0x20a0 fs/namei.c:4893 ... </TASK>

An issue was discovered in the Linux kernel before 5.9.3. io_uring takes a non-refcounted reference to the files_struct of the process that submitted a request, causing execve() to incorrectly optimize unshare_fd(), aka CID-0f2122045b94.

In the Linux kernel, the following vulnerability has been resolved: nfsd: clear acl_access/acl_default after releasing them If getting acl_default fails, acl_access and acl_default will be released simultaneously. However, acl_access will still retain a pointer pointing to the released posix_acl, which will trigger a WARNING in nfs3svc_release_getacl like this: ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 26 PID: 3199 at lib/refcount.c:28 refcount_warn_saturate+0xb5/0x170 Modules linked in: CPU: 26 UID: 0 PID: 3199 Comm: nfsd Not tainted 6.12.0-rc6-00079-g04ae226af01f-dirty #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:refcount_warn_saturate+0xb5/0x170 Code: cc cc 0f b6 1d b3 20 a5 03 80 fb 01 0f 87 65 48 d8 00 83 e3 01 75 e4 48 c7 c7 c0 3b 9b 85 c6 05 97 20 a5 03 01 e8 fb 3e 30 ff <0f> 0b eb cd 0f b6 1d 8a3 RSP: 0018:ffffc90008637cd8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff83904fde RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88871ed36380 RBP: ffff888158beeb40 R08: 0000000000000001 R09: fffff520010c6f56 R10: ffffc90008637ab7 R11: 0000000000000001 R12: 0000000000000001 R13: ffff888140e77400 R14: ffff888140e77408 R15: ffffffff858b42c0 FS: 0000000000000000(0000) GS:ffff88871ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562384d32158 CR3: 000000055cc6a000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? refcount_warn_saturate+0xb5/0x170 ? __warn+0xa5/0x140 ? refcount_warn_saturate+0xb5/0x170 ? report_bug+0x1b1/0x1e0 ? handle_bug+0x53/0xa0 ? exc_invalid_op+0x17/0x40 ? asm_exc_invalid_op+0x1a/0x20 ? tick_nohz_tick_stopped+0x1e/0x40 ? refcount_warn_saturate+0xb5/0x170 ? refcount_warn_saturate+0xb5/0x170 nfs3svc_release_getacl+0xc9/0xe0 svc_process_common+0x5db/0xb60 ? __pfx_svc_process_common+0x10/0x10 ? __rcu_read_unlock+0x69/0xa0 ? __pfx_nfsd_dispatch+0x10/0x10 ? svc_xprt_received+0xa1/0x120 ? xdr_init_decode+0x11d/0x190 svc_process+0x2a7/0x330 svc_handle_xprt+0x69d/0x940 svc_recv+0x180/0x2d0 nfsd+0x168/0x200 ? __pfx_nfsd+0x10/0x10 kthread+0x1a2/0x1e0 ? kthread+0xf4/0x1e0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x34/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Kernel panic - not syncing: kernel: panic_on_warn set ... Clear acl_access/acl_default after posix_acl_release is called to prevent UAF from being triggered.

A flaw was found in the Linux kernel’s implementation of MIDI, where an attacker with a local account and the permissions to issue ioctl commands to midi devices could trigger a use-after-free issue. A write to this specific memory while freed and before use causes the flow of execution to change and possibly allow for memory corruption or privilege escalation. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

A vulnerability was found in Linux Kernel, where a refcount leak in llcp_sock_connect() causing use-after-free which might lead to privilege escalations.

get_gate_page in mm/gup.c in the Linux kernel 5.7.x and 5.8.x before 5.8.7 allows privilege escalation because of incorrect reference counting (caused by gate page mishandling) of the struct page that backs the vsyscall page. The result is a refcount underflow. This can be triggered by any 64-bit process that can use ptrace() or process_vm_readv(), aka CID-9fa2dd946743.

An issue was discovered in Xen through 4.14.x. The PCI passthrough code improperly uses register data. Code paths in Xen's MSI handling have been identified that act on unsanitized values read back from device hardware registers. While devices strictly compliant with PCI specifications shouldn't be able to affect these registers, experience shows that it's very common for devices to have out-of-spec "backdoor" operations that can affect the result of these reads. A not fully trusted guest may be able to crash Xen, leading to a Denial of Service (DoS) for the entire system. Privilege escalation and information leaks cannot be excluded. All versions of Xen supporting PCI passthrough are affected. Only x86 systems are vulnerable. Arm systems are not vulnerable. Only guests with passed through PCI devices may be able to leverage the vulnerability. Only systems passing through devices with out-of-spec ("backdoor") functionality can cause issues. Experience shows that such out-of-spec functionality is common; unless you have reason to believe that your device does not have such functionality, it's better to assume that it does.

NVIDIA GPU Display Driver for Linux contains a vulnerability in the kernel mode layer, where improper restriction of operations within the bounds of a memory buffer can lead to denial of service, information disclosure, and data tampering.

A flaw was found in the Linux Kernel in RDS (Reliable Datagram Sockets) protocol. The rds_rm_zerocopy_callback() uses list_entry() on the head of a list causing a type confusion. Local user can trigger this with rds_message_put(). Type confusion leads to `struct rds_msg_zcopy_info *info` actually points to something else that is potentially controlled by local user. It is known how to trigger this, which causes an out of bounds access, and a lock corruption.

NVIDIA GPU Display Driver for Linux contains a vulnerability in the kernel mode layer handler which may lead to code execution, denial of service, escalation of privileges, information disclosure, and data tampering.

In the Linux kernel, the following vulnerability has been resolved: nfsd: under NFSv4.1, fix double svc_xprt_put on rpc_create failure On error situation `clp->cl_cb_conn.cb_xprt` should not be given a reference to the xprt otherwise both client cleanup and the error handling path of the caller call to put it. Better to delay handing over the reference to a later branch. [ 72.530665] refcount_t: underflow; use-after-free. [ 72.531933] WARNING: CPU: 0 PID: 173 at lib/refcount.c:28 refcount_warn_saturate+0xcf/0x120 [ 72.533075] Modules linked in: nfsd(OE) nfsv4(OE) nfsv3(OE) nfs(OE) lockd(OE) compat_nfs_ssc(OE) nfs_acl(OE) rpcsec_gss_krb5(OE) auth_rpcgss(OE) rpcrdma(OE) dns_resolver fscache netfs grace rdma_cm iw_cm ib_cm sunrpc(OE) mlx5_ib mlx5_core mlxfw pci_hyperv_intf ib_uverbs ib_core xt_MASQUERADE nf_conntrack_netlink nft_counter xt_addrtype nft_compat br_netfilter bridge stp llc nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set overlay nf_tables nfnetlink crct10dif_pclmul crc32_pclmul ghash_clmulni_intel xfs serio_raw virtio_net virtio_blk net_failover failover fuse [last unloaded: sunrpc] [ 72.540389] CPU: 0 PID: 173 Comm: kworker/u16:5 Tainted: G OE 5.15.82-dan #1 [ 72.541511] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-3.module+el8.7.0+1084+97b81f61 04/01/2014 [ 72.542717] Workqueue: nfsd4_callbacks nfsd4_run_cb_work [nfsd] [ 72.543575] RIP: 0010:refcount_warn_saturate+0xcf/0x120 [ 72.544299] Code: 55 00 0f 0b 5d e9 01 50 98 00 80 3d 75 9e 39 08 00 0f 85 74 ff ff ff 48 c7 c7 e8 d1 60 8e c6 05 61 9e 39 08 01 e8 f6 51 55 00 <0f> 0b 5d e9 d9 4f 98 00 80 3d 4b 9e 39 08 00 0f 85 4c ff ff ff 48 [ 72.546666] RSP: 0018:ffffb3f841157cf0 EFLAGS: 00010286 [ 72.547393] RAX: 0000000000000026 RBX: ffff89ac6231d478 RCX: 0000000000000000 [ 72.548324] RDX: ffff89adb7c2c2c0 RSI: ffff89adb7c205c0 RDI: ffff89adb7c205c0 [ 72.549271] RBP: ffffb3f841157cf0 R08: 0000000000000000 R09: c0000000ffefffff [ 72.550209] R10: 0000000000000001 R11: ffffb3f841157ad0 R12: ffff89ac6231d180 [ 72.551142] R13: ffff89ac6231d478 R14: ffff89ac40c06180 R15: ffff89ac6231d4b0 [ 72.552089] FS: 0000000000000000(0000) GS:ffff89adb7c00000(0000) knlGS:0000000000000000 [ 72.553175] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 72.553934] CR2: 0000563a310506a8 CR3: 0000000109a66000 CR4: 0000000000350ef0 [ 72.554874] Call Trace: [ 72.555278] <TASK> [ 72.555614] svc_xprt_put+0xaf/0xe0 [sunrpc] [ 72.556276] nfsd4_process_cb_update.isra.11+0xb7/0x410 [nfsd] [ 72.557087] ? update_load_avg+0x82/0x610 [ 72.557652] ? cpuacct_charge+0x60/0x70 [ 72.558212] ? dequeue_entity+0xdb/0x3e0 [ 72.558765] ? queued_spin_unlock+0x9/0x20 [ 72.559358] nfsd4_run_cb_work+0xfc/0x270 [nfsd] [ 72.560031] process_one_work+0x1df/0x390 [ 72.560600] worker_thread+0x37/0x3b0 [ 72.561644] ? process_one_work+0x390/0x390 [ 72.562247] kthread+0x12f/0x150 [ 72.562710] ? set_kthread_struct+0x50/0x50 [ 72.563309] ret_from_fork+0x22/0x30 [ 72.563818] </TASK> [ 72.564189] ---[ end trace 031117b1c72ec616 ]--- [ 72.566019] list_add corruption. next->prev should be prev (ffff89ac4977e538), but was ffff89ac4763e018. (next=ffff89ac4763e018). [ 72.567647] ------------[ cut here ]------------

In the Linux kernel, the following vulnerability has been resolved: media: dvb-core: Fix double free in dvb_register_device() In function dvb_register_device() -> dvb_register_media_device() -> dvb_create_media_entity(), dvb->entity is allocated and initialized. If the initialization fails, it frees the dvb->entity, and return an error code. The caller takes the error code and handles the error by calling dvb_media_device_free(), which unregisters the entity and frees the field again if it is not NULL. As dvb->entity may not NULLed in dvb_create_media_entity() when the allocation of dvbdev->pad fails, a double free may occur. This may also cause an Use After free in media_device_unregister_entity(). Fix this by storing NULL to dvb->entity when it is freed.

In the Linux kernel, the following vulnerability has been resolved: ath9k: fix use-after-free in ath9k_hif_usb_rx_cb Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb() [0]. The problem was in incorrect htc_handle->drv_priv initialization. Probable call trace which can trigger use-after-free: ath9k_htc_probe_device() /* htc_handle->drv_priv = priv; */ ath9k_htc_wait_for_target() <--- Failed ieee80211_free_hw() <--- priv pointer is freed <IRQ> ... ath9k_hif_usb_rx_cb() ath9k_hif_usb_rx_stream() RX_STAT_INC() <--- htc_handle->drv_priv access In order to not add fancy protection for drv_priv we can move htc_handle->drv_priv initialization at the end of the ath9k_htc_probe_device() and add helper macro to make all *_STAT_* macros NULL safe, since syzbot has reported related NULL deref in that macros [1]

In the Linux kernel, the following vulnerability has been resolved: parisc: Fix locking in pdc_iodc_print() firmware call Utilize pdc_lock spinlock to protect parallel modifications of the iodc_dbuf[] buffer, check length to prevent buffer overflow of iodc_dbuf[], drop the iodc_retbuf[] buffer and fix some wrong indentings.

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix uaf for bfqq in bfq_exit_icq_bfqq Commit 64dc8c732f5c ("block, bfq: fix possible uaf for 'bfqq->bic'") will access 'bic->bfqq' in bic_set_bfqq(), however, bfq_exit_icq_bfqq() can free bfqq first, and then call bic_set_bfqq(), which will cause uaf. Fix the problem by moving bfq_exit_bfqq() behind bic_set_bfqq().

In the Linux kernel, the following vulnerability has been resolved: media: si470x: Fix use-after-free in si470x_int_in_callback() syzbot reported use-after-free in si470x_int_in_callback() [1]. This indicates that urb->context, which contains struct si470x_device object, is freed when si470x_int_in_callback() is called. The cause of this issue is that si470x_int_in_callback() is called for freed urb. si470x_usb_driver_probe() calls si470x_start_usb(), which then calls usb_submit_urb() and si470x_start(). If si470x_start_usb() fails, si470x_usb_driver_probe() doesn't kill urb, but it just frees struct si470x_device object, as depicted below: si470x_usb_driver_probe() ... si470x_start_usb() ... usb_submit_urb() retval = si470x_start() return retval if (retval < 0) free struct si470x_device object, but don't kill urb This patch fixes this issue by killing urb when si470x_start_usb() fails and urb is submitted. If si470x_start_usb() fails and urb is not submitted, i.e. submitting usb fails, it just frees struct si470x_device object.

In the Linux kernel, the following vulnerability has been resolved: io_uring/af_unix: defer registered files gc to io_uring release Instead of putting io_uring's registered files in unix_gc() we want it to be done by io_uring itself. The trick here is to consider io_uring registered files for cycle detection but not actually putting them down. Because io_uring can't register other ring instances, this will remove all refs to the ring file triggering the ->release path and clean up with io_ring_ctx_free(). [axboe: add kerneldoc comment to skb, fold in skb leak fix]

In the Linux kernel, the following vulnerability has been resolved: RDMA/srpt: Fix a use-after-free Change the LIO port members inside struct srpt_port from regular members into pointers. Allocate the LIO port data structures from inside srpt_make_tport() and free these from inside srpt_make_tport(). Keep struct srpt_device as long as either an RDMA port or a LIO target port is associated with it. This patch decouples the lifetime of struct srpt_port (controlled by the RDMA core) and struct srpt_port_id (controlled by LIO). This patch fixes the following KASAN complaint: BUG: KASAN: use-after-free in srpt_enable_tpg+0x31/0x70 [ib_srpt] Read of size 8 at addr ffff888141cc34b8 by task check/5093 Call Trace: <TASK> show_stack+0x4e/0x53 dump_stack_lvl+0x51/0x66 print_address_description.constprop.0.cold+0xea/0x41e print_report.cold+0x90/0x205 kasan_report+0xb9/0xf0 __asan_load8+0x69/0x90 srpt_enable_tpg+0x31/0x70 [ib_srpt] target_fabric_tpg_base_enable_store+0xe2/0x140 [target_core_mod] configfs_write_iter+0x18b/0x210 new_sync_write+0x1f2/0x2f0 vfs_write+0x3e3/0x540 ksys_write+0xbb/0x140 __x64_sys_write+0x42/0x50 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 </TASK>

In the Linux kernel, the following vulnerability has been resolved: HID: mcp2221: prevent a buffer overflow in mcp_smbus_write() Smatch Warning: drivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy() '&mcp->txbuf[5]' too small (59 vs 255) drivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy() 'buf' too small (34 vs 255) The 'len' variable can take a value between 0-255 as it can come from data->block[0] and it is user data. So add an bound check to prevent a buffer overflow in memcpy().

In the Linux kernel, the following vulnerability has been resolved: ALSA: bcd2000: Fix a UAF bug on the error path of probing When the driver fails in snd_card_register() at probe time, it will free the 'bcd2k->midi_out_urb' before killing it, which may cause a UAF bug. The following log can reveal it: [ 50.727020] BUG: KASAN: use-after-free in bcd2000_input_complete+0x1f1/0x2e0 [snd_bcd2000] [ 50.727623] Read of size 8 at addr ffff88810fab0e88 by task swapper/4/0 [ 50.729530] Call Trace: [ 50.732899] bcd2000_input_complete+0x1f1/0x2e0 [snd_bcd2000] Fix this by adding usb_kill_urb() before usb_free_urb().

In the Linux kernel, the following vulnerability has been resolved: video: fbdev: vt8623fb: Check the size of screen before memset_io() In the function vt8623fb_set_par(), the value of 'screen_size' is calculated by the user input. If the user provides the improper value, the value of 'screen_size' may larger than 'info->screen_size', which may cause the following bug: [ 583.339036] BUG: unable to handle page fault for address: ffffc90005000000 [ 583.339049] #PF: supervisor write access in kernel mode [ 583.339052] #PF: error_code(0x0002) - not-present page [ 583.339074] RIP: 0010:memset_orig+0x33/0xb0 [ 583.339110] Call Trace: [ 583.339118] vt8623fb_set_par+0x11cd/0x21e0 [ 583.339146] fb_set_var+0x604/0xeb0 [ 583.339181] do_fb_ioctl+0x234/0x670 [ 583.339209] fb_ioctl+0xdd/0x130 Fix the this by checking the value of 'screen_size' before memset_io().

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dp: fix memory corruption with too many bridges Add the missing sanity check on the bridge counter to avoid corrupting data beyond the fixed-sized bridge array in case there are ever more than eight bridges. Patchwork: https://patchwork.freedesktop.org/patch/502664/

In the Linux kernel, the following vulnerability has been resolved: fs: fix UAF/GPF bug in nilfs_mdt_destroy In alloc_inode, inode_init_always() could return -ENOMEM if security_inode_alloc() fails, which causes inode->i_private uninitialized. Then nilfs_is_metadata_file_inode() returns true and nilfs_free_inode() wrongly calls nilfs_mdt_destroy(), which frees the uninitialized inode->i_private and leads to crashes(e.g., UAF/GPF). Fix this by moving security_inode_alloc just prior to this_cpu_inc(nr_inodes)

In the Linux kernel, the following vulnerability has been resolved: posix-cpu-timers: Cleanup CPU timers before freeing them during exec Commit 55e8c8eb2c7b ("posix-cpu-timers: Store a reference to a pid not a task") started looking up tasks by PID when deleting a CPU timer. When a non-leader thread calls execve, it will switch PIDs with the leader process. Then, as it calls exit_itimers, posix_cpu_timer_del cannot find the task because the timer still points out to the old PID. That means that armed timers won't be disarmed, that is, they won't be removed from the timerqueue_list. exit_itimers will still release their memory, and when that list is later processed, it leads to a use-after-free. Clean up the timers from the de-threaded task before freeing them. This prevents a reported use-after-free.

In the Linux kernel, the following vulnerability has been resolved: drm: bridge: adv7511: unregister cec i2c device after cec adapter cec_unregister_adapter() assumes that the underlying adapter ops are callable. For example, if the CEC adapter currently has a valid physical address, then the unregistration procedure will invalidate the physical address by setting it to f.f.f.f. Whence the following kernel oops observed after removing the adv7511 module: Unable to handle kernel execution of user memory at virtual address 0000000000000000 Internal error: Oops: 86000004 [#1] PREEMPT_RT SMP Call trace: 0x0 adv7511_cec_adap_log_addr+0x1ac/0x1c8 [adv7511] cec_adap_unconfigure+0x44/0x90 [cec] __cec_s_phys_addr.part.0+0x68/0x230 [cec] __cec_s_phys_addr+0x40/0x50 [cec] cec_unregister_adapter+0xb4/0x118 [cec] adv7511_remove+0x60/0x90 [adv7511] i2c_device_remove+0x34/0xe0 device_release_driver_internal+0x114/0x1f0 driver_detach+0x54/0xe0 bus_remove_driver+0x60/0xd8 driver_unregister+0x34/0x60 i2c_del_driver+0x2c/0x68 adv7511_exit+0x1c/0x67c [adv7511] __arm64_sys_delete_module+0x154/0x288 invoke_syscall+0x48/0x100 el0_svc_common.constprop.0+0x48/0xe8 do_el0_svc+0x28/0x88 el0_svc+0x1c/0x50 el0t_64_sync_handler+0xa8/0xb0 el0t_64_sync+0x15c/0x160 Code: bad PC value ---[ end trace 0000000000000000 ]--- Protect against this scenario by unregistering i2c_cec after unregistering the CEC adapter. Duly disable the CEC clock afterwards too.

In the Linux kernel, the following vulnerability has been resolved: xhci: Remove device endpoints from bandwidth list when freeing the device Endpoints are normally deleted from the bandwidth list when they are dropped, before the virt device is freed. If xHC host is dying or being removed then the endpoints aren't dropped cleanly due to functions returning early to avoid interacting with a non-accessible host controller. So check and delete endpoints that are still on the bandwidth list when freeing the virt device. Solves a list_del corruption kernel crash when unbinding xhci-pci, caused by xhci_mem_cleanup() when it later tried to delete already freed endpoints from the bandwidth list. This only affects hosts that use software bandwidth checking, which currenty is only the xHC in intel Panther Point PCH (Ivy Bridge)

In the Linux kernel, the following vulnerability has been resolved: intel_th: msu: Fix vmalloced buffers After commit f5ff79fddf0e ("dma-mapping: remove CONFIG_DMA_REMAP") there's a chance of DMA buffer getting allocated via vmalloc(), which messes up the mmapping code: > RIP: msc_mmap_fault [intel_th_msu] > Call Trace: > <TASK> > __do_fault > do_fault ... Fix this by accounting for vmalloc possibility.

In the Linux kernel, the following vulnerability has been resolved: NFSD: Protect against send buffer overflow in NFSv2 READDIR Restore the previous limit on the @count argument to prevent a buffer overflow attack.

In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: ipc3-topology: Prevent double freeing of ipc_control_data via load_bytes We have sanity checks for byte controls and if any of the fail the locally allocated scontrol->ipc_control_data is freed up, but not set to NULL. On a rollback path of the error the higher level code will also try to free the scontrol->ipc_control_data which will eventually going to lead to memory corruption as double freeing memory is not a good thing.

In the Linux kernel, the following vulnerability has been resolved: dm raid: fix address sanitizer warning in raid_resume There is a KASAN warning in raid_resume when running the lvm test lvconvert-raid.sh. The reason for the warning is that mddev->raid_disks is greater than rs->raid_disks, so the loop touches one entry beyond the allocated length.

In the Linux kernel, the following vulnerability has been resolved: iommu/omap: Fix buffer overflow in debugfs There are two issues here: 1) The "len" variable needs to be checked before the very first write. Otherwise if omap2_iommu_dump_ctx() with "bytes" less than 32 it is a buffer overflow. 2) The snprintf() function returns the number of bytes that *would* have been copied if there were enough space. But we want to know the number of bytes which were *actually* copied so use scnprintf() instead.

In the Linux kernel, the following vulnerability has been resolved: media: dvbdev: adopts refcnt to avoid UAF dvb_unregister_device() is known that prone to use-after-free. That is, the cleanup from dvb_unregister_device() releases the dvb_device even if there are pointers stored in file->private_data still refer to it. This patch adds a reference counter into struct dvb_device and delays its deallocation until no pointer refers to the object.

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scpi: Ensure scpi_info is not assigned if the probe fails When scpi probe fails, at any point, we need to ensure that the scpi_info is not set and will remain NULL until the probe succeeds. If it is not taken care, then it could result use-after-free as the value is exported via get_scpi_ops() and could refer to a memory allocated via devm_kzalloc() but freed when the probe fails.

In the Linux kernel, the following vulnerability has been resolved: video: fbdev: arkfb: Check the size of screen before memset_io() In the function arkfb_set_par(), the value of 'screen_size' is calculated by the user input. If the user provides the improper value, the value of 'screen_size' may larger than 'info->screen_size', which may cause the following bug: [ 659.399066] BUG: unable to handle page fault for address: ffffc90003000000 [ 659.399077] #PF: supervisor write access in kernel mode [ 659.399079] #PF: error_code(0x0002) - not-present page [ 659.399094] RIP: 0010:memset_orig+0x33/0xb0 [ 659.399116] Call Trace: [ 659.399122] arkfb_set_par+0x143f/0x24c0 [ 659.399130] fb_set_var+0x604/0xeb0 [ 659.399161] do_fb_ioctl+0x234/0x670 [ 659.399189] fb_ioctl+0xdd/0x130 Fix the this by checking the value of 'screen_size' before memset_io().

A flaw was found in the Linux kernel before 5.9-rc4. Memory corruption can be exploited to gain root privileges from unprivileged processes. The highest threat from this vulnerability is to data confidentiality and integrity.

In the Linux kernel, the following vulnerability has been resolved: android: binder: stop saving a pointer to the VMA Do not record a pointer to a VMA outside of the mmap_lock for later use. This is unsafe and there are a number of failure paths *after* the recorded VMA pointer may be freed during setup. There is no callback to the driver to clear the saved pointer from generic mm code. Furthermore, the VMA pointer may become stale if any number of VMA operations end up freeing the VMA so saving it was fragile to being with. Instead, change the binder_alloc struct to record the start address of the VMA and use vma_lookup() to get the vma when needed. Add lockdep mmap_lock checks on updates to the vma pointer to ensure the lock is held and depend on that lock for synchronization of readers and writers - which was already the case anyways, so the smp_wmb()/smp_rmb() was not necessary. [akpm@linux-foundation.org: fix drivers/android/binder_alloc_selftest.c]

A flaw was found in the Linux kernel’s futex implementation. This flaw allows a local attacker to corrupt system memory or escalate their privileges when creating a futex on a filesystem that is about to be unmounted. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

In the Linux kernel, the following vulnerability has been resolved: mtd: core: add missing of_node_get() in dynamic partitions code This fixes unbalanced of_node_put(): [ 1.078910] 6 cmdlinepart partitions found on MTD device gpmi-nand [ 1.085116] Creating 6 MTD partitions on "gpmi-nand": [ 1.090181] 0x000000000000-0x000008000000 : "nandboot" [ 1.096952] 0x000008000000-0x000009000000 : "nandfit" [ 1.103547] 0x000009000000-0x00000b000000 : "nandkernel" [ 1.110317] 0x00000b000000-0x00000c000000 : "nanddtb" [ 1.115525] ------------[ cut here ]------------ [ 1.120141] refcount_t: addition on 0; use-after-free. [ 1.125328] WARNING: CPU: 0 PID: 1 at lib/refcount.c:25 refcount_warn_saturate+0xdc/0x148 [ 1.133528] Modules linked in: [ 1.136589] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc7-next-20220930-04543-g8cf3f7 [ 1.146342] Hardware name: Freescale i.MX8DXL DDR3L EVK (DT) [ 1.151999] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1.158965] pc : refcount_warn_saturate+0xdc/0x148 [ 1.163760] lr : refcount_warn_saturate+0xdc/0x148 [ 1.168556] sp : ffff800009ddb080 [ 1.171866] x29: ffff800009ddb080 x28: ffff800009ddb35a x27: 0000000000000002 [ 1.179015] x26: ffff8000098b06ad x25: ffffffffffffffff x24: ffff0a00ffffff05 [ 1.186165] x23: ffff00001fdf6470 x22: ffff800009ddb367 x21: 0000000000000000 [ 1.193314] x20: ffff00001fdfebe8 x19: ffff00001fdfec50 x18: ffffffffffffffff [ 1.200464] x17: 0000000000000000 x16: 0000000000000118 x15: 0000000000000004 [ 1.207614] x14: 0000000000000fff x13: ffff800009bca248 x12: 0000000000000003 [ 1.214764] x11: 00000000ffffefff x10: c0000000ffffefff x9 : 4762cb2ccb52de00 [ 1.221914] x8 : 4762cb2ccb52de00 x7 : 205d313431303231 x6 : 312e31202020205b [ 1.229063] x5 : ffff800009d55c1f x4 : 0000000000000001 x3 : 0000000000000000 [ 1.236213] x2 : 0000000000000000 x1 : ffff800009954be6 x0 : 000000000000002a [ 1.243365] Call trace: [ 1.245806] refcount_warn_saturate+0xdc/0x148 [ 1.250253] kobject_get+0x98/0x9c [ 1.253658] of_node_get+0x20/0x34 [ 1.257072] of_fwnode_get+0x3c/0x54 [ 1.260652] fwnode_get_nth_parent+0xd8/0xf4 [ 1.264926] fwnode_full_name_string+0x3c/0xb4 [ 1.269373] device_node_string+0x498/0x5b4 [ 1.273561] pointer+0x41c/0x5d0 [ 1.276793] vsnprintf+0x4d8/0x694 [ 1.280198] vprintk_store+0x164/0x528 [ 1.283951] vprintk_emit+0x98/0x164 [ 1.287530] vprintk_default+0x44/0x6c [ 1.291284] vprintk+0xf0/0x134 [ 1.294428] _printk+0x54/0x7c [ 1.297486] of_node_release+0xe8/0x128 [ 1.301326] kobject_put+0x98/0xfc [ 1.304732] of_node_put+0x1c/0x28 [ 1.308137] add_mtd_device+0x484/0x6d4 [ 1.311977] add_mtd_partitions+0xf0/0x1d0 [ 1.316078] parse_mtd_partitions+0x45c/0x518 [ 1.320439] mtd_device_parse_register+0xb0/0x274 [ 1.325147] gpmi_nand_probe+0x51c/0x650 [ 1.329074] platform_probe+0xa8/0xd0 [ 1.332740] really_probe+0x130/0x334 [ 1.336406] __driver_probe_device+0xb4/0xe0 [ 1.340681] driver_probe_device+0x3c/0x1f8 [ 1.344869] __driver_attach+0xdc/0x1a4 [ 1.348708] bus_for_each_dev+0x80/0xcc [ 1.352548] driver_attach+0x24/0x30 [ 1.356127] bus_add_driver+0x108/0x1f4 [ 1.359967] driver_register+0x78/0x114 [ 1.363807] __platform_driver_register+0x24/0x30 [ 1.368515] gpmi_nand_driver_init+0x1c/0x28 [ 1.372798] do_one_initcall+0xbc/0x238 [ 1.376638] do_initcall_level+0x94/0xb4 [ 1.380565] do_initcalls+0x54/0x94 [ 1.384058] do_basic_setup+0x1c/0x28 [ 1.387724] kernel_init_freeable+0x110/0x188 [ 1.392084] kernel_init+0x20/0x1a0 [ 1.395578] ret_from_fork+0x10/0x20 [ 1.399157] ---[ end trace 0000000000000000 ]--- [ 1.403782] ------------[ cut here ]------------

In the Linux kernel, the following vulnerability has been resolved: bpf, x86: fix freeing of not-finalized bpf_prog_pack syzbot reported a few issues with bpf_prog_pack [1], [2]. This only happens with multiple subprogs. In jit_subprogs(), we first call bpf_int_jit_compile() on each sub program. And then, we call it on each sub program again. jit_data is not freed in the first call of bpf_int_jit_compile(). Similarly we don't call bpf_jit_binary_pack_finalize() in the first call of bpf_int_jit_compile(). If bpf_int_jit_compile() failed for one sub program, we will call bpf_jit_binary_pack_finalize() for this sub program. However, we don't have a chance to call it for other sub programs. Then we will hit "goto out_free" in jit_subprogs(), and call bpf_jit_free on some subprograms that haven't got bpf_jit_binary_pack_finalize() yet. At this point, bpf_jit_binary_pack_free() is called and the whole 2MB page is freed erroneously. Fix this with a custom bpf_jit_free() for x86_64, which calls bpf_jit_binary_pack_finalize() if necessary. Also, with custom bpf_jit_free(), bpf_prog_aux->use_bpf_prog_pack is not needed any more, remove it. [1] https://syzkaller.appspot.com/bug?extid=2f649ec6d2eea1495a8f [2] https://syzkaller.appspot.com/bug?extid=87f65c75f4a72db05445

In the Linux kernel, the following vulnerability has been resolved: ACPICA: Fix use-after-free in acpi_ut_copy_ipackage_to_ipackage() There is an use-after-free reported by KASAN: BUG: KASAN: use-after-free in acpi_ut_remove_reference+0x3b/0x82 Read of size 1 at addr ffff888112afc460 by task modprobe/2111 CPU: 0 PID: 2111 Comm: modprobe Not tainted 6.1.0-rc7-dirty Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), Call Trace: <TASK> kasan_report+0xae/0xe0 acpi_ut_remove_reference+0x3b/0x82 acpi_ut_copy_iobject_to_iobject+0x3be/0x3d5 acpi_ds_store_object_to_local+0x15d/0x3a0 acpi_ex_store+0x78d/0x7fd acpi_ex_opcode_1A_1T_1R+0xbe4/0xf9b acpi_ps_parse_aml+0x217/0x8d5 ... </TASK> The root cause of the problem is that the acpi_operand_object is freed when acpi_ut_walk_package_tree() fails in acpi_ut_copy_ipackage_to_ipackage(), lead to repeated release in acpi_ut_copy_iobject_to_iobject(). The problem was introduced by "8aa5e56eeb61" commit, this commit is to fix memory leak in acpi_ut_copy_iobject_to_iobject(), repeatedly adding remove operation, lead to "acpi_operand_object" used after free. Fix it by removing acpi_ut_remove_reference() in acpi_ut_copy_ipackage_to_ipackage(). acpi_ut_copy_ipackage_to_ipackage() is called to copy an internal package object into another internal package object, when it fails, the memory of acpi_operand_object should be freed by the caller.

In the Linux kernel, the following vulnerability has been resolved: ASoC: Intel: avs: Fix potential RX buffer overflow If an event caused firmware to return invalid RX size for LARGE_CONFIG_GET, memcpy_fromio() could end up copying too many bytes. Fix by utilizing min_t().

In the Linux kernel, the following vulnerability has been resolved: scsi: zfcp: Fix double free of FSF request when qdio send fails We used to use the wrong type of integer in 'zfcp_fsf_req_send()' to cache the FSF request ID when sending a new FSF request. This is used in case the sending fails and we need to remove the request from our internal hash table again (so we don't keep an invalid reference and use it when we free the request again). In 'zfcp_fsf_req_send()' we used to cache the ID as 'int' (signed and 32 bit wide), but the rest of the zfcp code (and the firmware specification) handles the ID as 'unsigned long'/'u64' (unsigned and 64 bit wide [s390x ELF ABI]). For one this has the obvious problem that when the ID grows past 32 bit (this can happen reasonably fast) it is truncated to 32 bit when storing it in the cache variable and so doesn't match the original ID anymore. The second less obvious problem is that even when the original ID has not yet grown past 32 bit, as soon as the 32nd bit is set in the original ID (0x80000000 = 2'147'483'648) we will have a mismatch when we cast it back to 'unsigned long'. As the cached variable is of a signed type, the compiler will choose a sign-extending instruction to load the 32 bit variable into a 64 bit register (e.g.: 'lgf %r11,188(%r15)'). So once we pass the cached variable into 'zfcp_reqlist_find_rm()' to remove the request again all the leading zeros will be flipped to ones to extend the sign and won't match the original ID anymore (this has been observed in practice). If we can't successfully remove the request from the hash table again after 'zfcp_qdio_send()' fails (this happens regularly when zfcp cannot notify the adapter about new work because the adapter is already gone during e.g. a ChpID toggle) we will end up with a double free. We unconditionally free the request in the calling function when 'zfcp_fsf_req_send()' fails, but because the request is still in the hash table we end up with a stale memory reference, and once the zfcp adapter is either reset during recovery or shutdown we end up freeing the same memory twice. The resulting stack traces vary depending on the kernel and have no direct correlation to the place where the bug occurs. Here are three examples that have been seen in practice: list_del corruption. next->prev should be 00000001b9d13800, but was 00000000dead4ead. (next=00000001bd131a00) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:62! monitor event: 0040 ilc:2 [#1] PREEMPT SMP Modules linked in: ... CPU: 9 PID: 1617 Comm: zfcperp0.0.1740 Kdump: loaded Hardware name: ... Krnl PSW : 0704d00180000000 00000003cbeea1f8 (__list_del_entry_valid+0x98/0x140) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3 Krnl GPRS: 00000000916d12f1 0000000080000000 000000000000006d 00000003cb665cd6 0000000000000001 0000000000000000 0000000000000000 00000000d28d21e8 00000000d3844000 00000380099efd28 00000001bd131a00 00000001b9d13800 00000000d3290100 0000000000000000 00000003cbeea1f4 00000380099efc70 Krnl Code: 00000003cbeea1e8: c020004f68a7 larl %r2,00000003cc8d7336 00000003cbeea1ee: c0e50027fd65 brasl %r14,00000003cc3e9cb8 #00000003cbeea1f4: af000000 mc 0,0 >00000003cbeea1f8: c02000920440 larl %r2,00000003cd12aa78 00000003cbeea1fe: c0e500289c25 brasl %r14,00000003cc3fda48 00000003cbeea204: b9040043 lgr %r4,%r3 00000003cbeea208: b9040051 lgr %r5,%r1 00000003cbeea20c: b9040032 lgr %r3,%r2 Call Trace: [<00000003cbeea1f8>] __list_del_entry_valid+0x98/0x140 ([<00000003cbeea1f4>] __list_del_entry_valid+0x94/0x140) [<000003ff7ff502fe>] zfcp_fsf_req_dismiss_all+0xde/0x150 [zfcp] [<000003ff7ff49cd0>] zfcp_erp_strategy_do_action+0x160/0x280 [zfcp] ---truncated---

A flaw null pointer dereference in the Linux kernel cgroupv2 subsystem in versions before 5.7.10 was found in the way when reboot the system. A local user could use this flaw to crash the system or escalate their privileges on the system.

In the Linux kernel, the following vulnerability has been resolved: ipvs: fix WARNING in ip_vs_app_net_cleanup() During the initialization of ip_vs_app_net_init(), if file ip_vs_app fails to be created, the initialization is successful by default. Therefore, the ip_vs_app file doesn't be found during the remove in ip_vs_app_net_cleanup(). It will cause WRNING. The following is the stack information: name 'ip_vs_app' WARNING: CPU: 1 PID: 9 at fs/proc/generic.c:712 remove_proc_entry+0x389/0x460 Modules linked in: Workqueue: netns cleanup_net RIP: 0010:remove_proc_entry+0x389/0x460 Call Trace: <TASK> ops_exit_list+0x125/0x170 cleanup_net+0x4ea/0xb00 process_one_work+0x9bf/0x1710 worker_thread+0x665/0x1080 kthread+0x2e4/0x3a0 ret_from_fork+0x1f/0x30 </TASK>

In the Linux kernel, the following vulnerability has been resolved: btrfs: do not clean up repair bio if submit fails The submit helper will always run bio_endio() on the bio if it fails to submit, so cleaning up the bio just leads to a variety of use-after-free and NULL pointer dereference bugs because we race with the endio function that is cleaning up the bio. Instead just return BLK_STS_OK as the repair function has to continue to process the rest of the pages, and the endio for the repair bio will do the appropriate cleanup for the page that it was given.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: fix dangling sco_conn and use-after-free in sco_sock_timeout Connecting the same socket twice consecutively in sco_sock_connect() could lead to a race condition where two sco_conn objects are created but only one is associated with the socket. If the socket is closed before the SCO connection is established, the timer associated with the dangling sco_conn object won't be canceled. As the sock object is being freed, the use-after-free problem happens when the timer callback function sco_sock_timeout() accesses the socket. Here's the call trace: dump_stack+0x107/0x163 ? refcount_inc+0x1c/ print_address_description.constprop.0+0x1c/0x47e ? refcount_inc+0x1c/0x7b kasan_report+0x13a/0x173 ? refcount_inc+0x1c/0x7b check_memory_region+0x132/0x139 refcount_inc+0x1c/0x7b sco_sock_timeout+0xb2/0x1ba process_one_work+0x739/0xbd1 ? cancel_delayed_work+0x13f/0x13f ? __raw_spin_lock_init+0xf0/0xf0 ? to_kthread+0x59/0x85 worker_thread+0x593/0x70e kthread+0x346/0x35a ? drain_workqueue+0x31a/0x31a ? kthread_bind+0x4b/0x4b ret_from_fork+0x1f/0x30

In the Linux kernel, the following vulnerability has been resolved: s390: fix double free of GS and RI CBs on fork() failure The pointers for guarded storage and runtime instrumentation control blocks are stored in the thread_struct of the associated task. These pointers are initially copied on fork() via arch_dup_task_struct() and then cleared via copy_thread() before fork() returns. If fork() happens to fail after the initial task dup and before copy_thread(), the newly allocated task and associated thread_struct memory are freed via free_task() -> arch_release_task_struct(). This results in a double free of the guarded storage and runtime info structs because the fields in the failed task still refer to memory associated with the source task. This problem can manifest as a BUG_ON() in set_freepointer() (with CONFIG_SLAB_FREELIST_HARDENED enabled) or KASAN splat (if enabled) when running trinity syscall fuzz tests on s390x. To avoid this problem, clear the associated pointer fields in arch_dup_task_struct() immediately after the new task is copied. Note that the RI flag is still cleared in copy_thread() because it resides in thread stack memory and that is where stack info is copied.

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8712: fix use after free bugs _Read/Write_MACREG callbacks are NULL so the read/write_macreg_hdl() functions don't do anything except free the "pcmd" pointer. It results in a use after free. Delete them.

In the Linux kernel, the following vulnerability has been resolved: bfq: Avoid merging queues with different parents It can happen that the parent of a bfqq changes between the moment we decide two queues are worth to merge (and set bic->stable_merge_bfqq) and the moment bfq_setup_merge() is called. This can happen e.g. because the process submitted IO for a different cgroup and thus bfqq got reparented. It can even happen that the bfqq we are merging with has parent cgroup that is already offline and going to be destroyed in which case the merge can lead to use-after-free issues such as: BUG: KASAN: use-after-free in __bfq_deactivate_entity+0x9cb/0xa50 Read of size 8 at addr ffff88800693c0c0 by task runc:[2:INIT]/10544 CPU: 0 PID: 10544 Comm: runc:[2:INIT] Tainted: G E 5.15.2-0.g5fb85fd-default #1 openSUSE Tumbleweed (unreleased) f1f3b891c72369aebecd2e43e4641a6358867c70 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014 Call Trace: <IRQ> dump_stack_lvl+0x46/0x5a print_address_description.constprop.0+0x1f/0x140 ? __bfq_deactivate_entity+0x9cb/0xa50 kasan_report.cold+0x7f/0x11b ? __bfq_deactivate_entity+0x9cb/0xa50 __bfq_deactivate_entity+0x9cb/0xa50 ? update_curr+0x32f/0x5d0 bfq_deactivate_entity+0xa0/0x1d0 bfq_del_bfqq_busy+0x28a/0x420 ? resched_curr+0x116/0x1d0 ? bfq_requeue_bfqq+0x70/0x70 ? check_preempt_wakeup+0x52b/0xbc0 __bfq_bfqq_expire+0x1a2/0x270 bfq_bfqq_expire+0xd16/0x2160 ? try_to_wake_up+0x4ee/0x1260 ? bfq_end_wr_async_queues+0xe0/0xe0 ? _raw_write_unlock_bh+0x60/0x60 ? _raw_spin_lock_irq+0x81/0xe0 bfq_idle_slice_timer+0x109/0x280 ? bfq_dispatch_request+0x4870/0x4870 __hrtimer_run_queues+0x37d/0x700 ? enqueue_hrtimer+0x1b0/0x1b0 ? kvm_clock_get_cycles+0xd/0x10 ? ktime_get_update_offsets_now+0x6f/0x280 hrtimer_interrupt+0x2c8/0x740 Fix the problem by checking that the parent of the two bfqqs we are merging in bfq_setup_merge() is the same.

In the Linux kernel, the following vulnerability has been resolved: net: bonding: fix use-after-free after 802.3ad slave unbind commit 0622cab0341c ("bonding: fix 802.3ad aggregator reselection"), resolve case, when there is several aggregation groups in the same bond. bond_3ad_unbind_slave will invalidate (clear) aggregator when __agg_active_ports return zero. So, ad_clear_agg can be executed even, when num_of_ports!=0. Than bond_3ad_unbind_slave can be executed again for, previously cleared aggregator. NOTE: at this time bond_3ad_unbind_slave will not update slave ports list, because lag_ports==NULL. So, here we got slave ports, pointing to freed aggregator memory. Fix with checking actual number of ports in group (as was before commit 0622cab0341c ("bonding: fix 802.3ad aggregator reselection") ), before ad_clear_agg(). The KASAN logs are as follows: [ 767.617392] ================================================================== [ 767.630776] BUG: KASAN: use-after-free in bond_3ad_state_machine_handler+0x13dc/0x1470 [ 767.638764] Read of size 2 at addr ffff00011ba9d430 by task kworker/u8:7/767 [ 767.647361] CPU: 3 PID: 767 Comm: kworker/u8:7 Tainted: G O 5.15.11 #15 [ 767.655329] Hardware name: DNI AmazonGo1 A7040 board (DT) [ 767.660760] Workqueue: lacp_1 bond_3ad_state_machine_handler [ 767.666468] Call trace: [ 767.668930] dump_backtrace+0x0/0x2d0 [ 767.672625] show_stack+0x24/0x30 [ 767.675965] dump_stack_lvl+0x68/0x84 [ 767.679659] print_address_description.constprop.0+0x74/0x2b8 [ 767.685451] kasan_report+0x1f0/0x260 [ 767.689148] __asan_load2+0x94/0xd0 [ 767.692667] bond_3ad_state_machine_handler+0x13dc/0x1470