In the Linux kernel, the following vulnerability has been resolved: drm/drm_file: Fix pid refcounting race <maarten.lankhorst@linux.intel.com>, Maxime Ripard <mripard@kernel.org>, Thomas Zimmermann <tzimmermann@suse.de> filp->pid is supposed to be a refcounted pointer; however, before this patch, drm_file_update_pid() only increments the refcount of a struct pid after storing a pointer to it in filp->pid and dropping the dev->filelist_mutex, making the following race possible: process A process B ========= ========= begin drm_file_update_pid mutex_lock(&dev->filelist_mutex) rcu_replace_pointer(filp->pid, <pid B>, 1) mutex_unlock(&dev->filelist_mutex) begin drm_file_update_pid mutex_lock(&dev->filelist_mutex) rcu_replace_pointer(filp->pid, <pid A>, 1) mutex_unlock(&dev->filelist_mutex) get_pid(<pid A>) synchronize_rcu() put_pid(<pid B>) *** pid B reaches refcount 0 and is freed here *** get_pid(<pid B>) *** UAF *** synchronize_rcu() put_pid(<pid A>) As far as I know, this race can only occur with CONFIG_PREEMPT_RCU=y because it requires RCU to detect a quiescent state in code that is not explicitly calling into the scheduler. This race leads to use-after-free of a "struct pid". It is probably somewhat hard to hit because process A has to pass through a synchronize_rcu() operation while process B is between mutex_unlock() and get_pid(). Fix it by ensuring that by the time a pointer to the current task's pid is stored in the file, an extra reference to the pid has been taken. This fix also removes the condition for synchronize_rcu(); I think that optimization is unnecessary complexity, since in that case we would usually have bailed out on the lockless check above.

linux

The CloudStack integration API service allows running its unauthenticated API server (usually on port 8096 when configured and enabled via integration.api.port global setting) for internal portal integrations and for testing purposes. By default, the integration API service port is disabled and is considered disabled when integration.api.port is set to 0 or negative. Due to an improper initialisation logic, the integration API service would listen on a random port when its port value is set to 0 (default value). An attacker that can access the CloudStack management network could scan and find the randomised integration API service port and exploit it to perform unauthorised administrative actions and perform remote code execution on CloudStack managed hosts and result in complete compromise of the confidentiality, integrity, and availability of CloudStack managed infrastructure. Users are recommended to restrict the network access on the CloudStack management server hosts to only essential ports. Users are recommended to upgrade to version 4.18.2.1, 4.19.0.2 or later, which addresses this issue.

apache

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on SRX Series and NFX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). If an affected device receives specific valid traffic destined to the device, it will cause the PFE to crash and restart. Continued receipt and processing of this traffic will create a sustained DoS condition. This issue affects Junos OS on SRX Series: * 21.4 versions before 21.4R3-S7.9, * 22.1 versions before 22.1R3-S5.3, * 22.2 versions before 22.2R3-S4.11, * 22.3 versions before 22.3R3, * 22.4 versions before 22.4R3. This issue affects Junos OS on NFX Series: * 21.4 versions before 21.4R3-S8, * 22.1 versions after 22.1R1, * 22.2 versions before 22.2R3-S5, * 22.3 versions before 22.3R3, * 22.4 versions before 22.4R3. Junos OS versions prior to 21.4R1 are not affected by this issue.

juniper

In the Linux kernel, the following vulnerability has been resolved: RDMA/ucma: Protect mc during concurrent multicast leaves Partially revert the commit mentioned in the Fixes line to make sure that allocation and erasing multicast struct are locked. BUG: KASAN: use-after-free in ucma_cleanup_multicast drivers/infiniband/core/ucma.c:491 [inline] BUG: KASAN: use-after-free in ucma_destroy_private_ctx+0x914/0xb70 drivers/infiniband/core/ucma.c:579 Read of size 8 at addr ffff88801bb74b00 by task syz-executor.1/25529 CPU: 0 PID: 25529 Comm: syz-executor.1 Not tainted 5.16.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 ucma_cleanup_multicast drivers/infiniband/core/ucma.c:491 [inline] ucma_destroy_private_ctx+0x914/0xb70 drivers/infiniband/core/ucma.c:579 ucma_destroy_id+0x1e6/0x280 drivers/infiniband/core/ucma.c:614 ucma_write+0x25c/0x350 drivers/infiniband/core/ucma.c:1732 vfs_write+0x28e/0xae0 fs/read_write.c:588 ksys_write+0x1ee/0x250 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Currently the xarray search can touch a concurrently freeing mc as the xa_for_each() is not surrounded by any lock. Rather than hold the lock for a full scan hold it only for the effected items, which is usually an empty list.

linux

In the Linux kernel, the following vulnerability has been resolved: jffs2: prevent xattr node from overflowing the eraseblock Add a check to make sure that the requested xattr node size is no larger than the eraseblock minus the cleanmarker. Unlike the usual inode nodes, the xattr nodes aren't split into parts and spread across multiple eraseblocks, which means that a xattr node must not occupy more than one eraseblock. If the requested xattr value is too large, the xattr node can spill onto the next eraseblock, overwriting the nodes and causing errors such as: jffs2: argh. node added in wrong place at 0x0000b050(2) jffs2: nextblock 0x0000a000, expected at 0000b00c jffs2: error: (823) do_verify_xattr_datum: node CRC failed at 0x01e050, read=0xfc892c93, calc=0x000000 jffs2: notice: (823) jffs2_get_inode_nodes: Node header CRC failed at 0x01e00c. {848f,2fc4,0fef511f,59a3d171} jffs2: Node at 0x0000000c with length 0x00001044 would run over the end of the erase block jffs2: Perhaps the file system was created with the wrong erase size? jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000010: 0x1044 instead This breaks the filesystem and can lead to KASAN crashes such as: BUG: KASAN: slab-out-of-bounds in jffs2_sum_add_kvec+0x125e/0x15d0 Read of size 4 at addr ffff88802c31e914 by task repro/830 CPU: 0 PID: 830 Comm: repro Not tainted 6.9.0-rc3+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0xc6/0x120 print_report+0xc4/0x620 ? __virt_addr_valid+0x308/0x5b0 kasan_report+0xc1/0xf0 ? jffs2_sum_add_kvec+0x125e/0x15d0 ? jffs2_sum_add_kvec+0x125e/0x15d0 jffs2_sum_add_kvec+0x125e/0x15d0 jffs2_flash_direct_writev+0xa8/0xd0 jffs2_flash_writev+0x9c9/0xef0 ? __x64_sys_setxattr+0xc4/0x160 ? do_syscall_64+0x69/0x140 ? entry_SYSCALL_64_after_hwframe+0x76/0x7e [...] Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

linux

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: Init `ddp_comp` with devm_kcalloc() In the case where `conn_routes` is true we allocate an extra slot in the `ddp_comp` array but mtk_drm_crtc_create() never seemed to initialize it in the test case I ran. For me, this caused a later crash when we looped through the array in mtk_drm_crtc_mode_valid(). This showed up for me when I booted with `slub_debug=FZPUA` which poisons the memory initially. Without `slub_debug` I couldn't reproduce, presumably because the later code handles the value being NULL and in most cases (not guaranteed in all cases) the memory the allocator returned started out as 0. It really doesn't hurt to initialize the array with devm_kcalloc() since the array is small and the overhead of initting a handful of elements to 0 is small. In general initting memory to zero is a safer practice and usually it's suggested to only use the non-initting alloc functions if you really need to. Let's switch the function to use an allocation function that zeros the memory. For me, this avoids the crash.

linux

Strapi is an open-source content management system. Prior to version 4.22.0, a denial-of-service vulnerability is present in the media upload process causing the server to crash without restarting, affecting either development and production environments. Usually, errors in the application cause it to log the error and keep it running for other clients. This behavior, in contrast, stops the server execution, making it unavailable for any clients until it's manually restarted. Any user with access to the file upload functionality is able to exploit this vulnerability, affecting applications running in both development mode and production mode as well. Users should upgrade @strapi/plugin-upload to version 4.22.0 to receive a patch.

strapi

The in-app browser of LINE client for iOS versions below 14.9.0 contains a Universal XSS (UXSS) vulnerability. This vulnerability allows for cross-site scripting (XSS) where arbitrary JavaScript can be executed in the top frame from an embedded iframe on any displayed web site within the in-app browser. The in-app browser is usually opened by tapping on URLs contained in chat messages, and for the attack to be successful, the victim must trigger a click event on a malicious iframe. If an iframe embedded in any website can be controlled by an attacker, this vulnerability could be exploited to capture or alter content displayed in the top frame, as well as user session information. This vulnerability affects LINE client for iOS versions below 14.9.0 and does not affect other LINE clients such as LINE client for Android. Please update LINE client for iOS to version 14.9.0 or higher.

linecorp

A heap-based buffer overflow vulnerability exists in the FOXMAN-UN/UNEM that if exploited will generally lead to a denial of service but can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy

hitachienergy

In the Linux kernel, the following vulnerability has been resolved: firewire: ohci: mask bus reset interrupts between ISR and bottom half In the FireWire OHCI interrupt handler, if a bus reset interrupt has occurred, mask bus reset interrupts until bus_reset_work has serviced and cleared the interrupt. Normally, we always leave bus reset interrupts masked. We infer the bus reset from the self-ID interrupt that happens shortly thereafter. A scenario where we unmask bus reset interrupts was introduced in 2008 in a007bb857e0b26f5d8b73c2ff90782d9c0972620: If OHCI_PARAM_DEBUG_BUSRESETS (8) is set in the debug parameter bitmask, we will unmask bus reset interrupts so we can log them. irq_handler logs the bus reset interrupt. However, we can't clear the bus reset event flag in irq_handler, because we won't service the event until later. irq_handler exits with the event flag still set. If the corresponding interrupt is still unmasked, the first bus reset will usually freeze the system due to irq_handler being called again each time it exits. This freeze can be reproduced by loading firewire_ohci with "modprobe firewire_ohci debug=-1" (to enable all debugging output). Apparently there are also some cases where bus_reset_work will get called soon enough to clear the event, and operation will continue normally. This freeze was first reported a few months after a007bb85 was committed, but until now it was never fixed. The debug level could safely be set to -1 through sysfs after the module was loaded, but this would be ineffectual in logging bus reset interrupts since they were only unmasked during initialization. irq_handler will now leave the event flag set but mask bus reset interrupts, so irq_handler won't be called again and there will be no freeze. If OHCI_PARAM_DEBUG_BUSRESETS is enabled, bus_reset_work will unmask the interrupt after servicing the event, so future interrupts will be caught as desired. As a side effect to this change, OHCI_PARAM_DEBUG_BUSRESETS can now be enabled through sysfs in addition to during initial module loading. However, when enabled through sysfs, logging of bus reset interrupts will be effective only starting with the second bus reset, after bus_reset_work has executed.

linux · debian

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: uvc: use correct buffer size when parsing configfs lists This commit fixes uvc gadget support on 32-bit platforms. Commit 0df28607c5cb ("usb: gadget: uvc: Generalise helper functions for reuse") introduced a helper function __uvcg_iter_item_entries() to aid with parsing lists of items on configfs attributes stores. This function is a generalization of another very similar function, which used a stack-allocated temporary buffer of fixed size for each item in the list and used the sizeof() operator to check for potential buffer overruns. The new function was changed to allocate the now variably sized temp buffer on heap, but wasn't properly updated to also check for max buffer size using the computed size instead of sizeof() operator. As a result, the maximum item size was 7 (plus null terminator) on 64-bit platforms, and 3 on 32-bit ones. While 7 is accidentally just barely enough, 3 is definitely too small for some of UVC configfs attributes. For example, dwFrameInteval, specified in 100ns units, usually has 6-digit item values, e.g. 166666 for 60fps.

linux

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix use-after-free due to delegation race A delegation break could arrive as soon as we've called vfs_setlease. A delegation break runs a callback which immediately (in nfsd4_cb_recall_prepare) adds the delegation to del_recall_lru. If we then exit nfs4_set_delegation without hashing the delegation, it will be freed as soon as the callback is done with it, without ever being removed from del_recall_lru. Symptoms show up later as use-after-free or list corruption warnings, usually in the laundromat thread. I suspect aba2072f4523 "nfsd: grant read delegations to clients holding writes" made this bug easier to hit, but I looked as far back as v3.0 and it looks to me it already had the same problem. So I'm not sure where the bug was introduced; it may have been there from the beginning.

linux

In the Linux kernel, the following vulnerability has been resolved: soc: qcom: llcc: Handle a second device without data corruption Usually there is only one llcc device. But if there were a second, even a failed probe call would modify the global drv_data pointer. So check if drv_data is valid before overwriting it.

linux

In the Linux kernel, the following vulnerability has been resolved: padata: Fix refcnt handling in padata_free_shell() In a high-load arm64 environment, the pcrypt_aead01 test in LTP can lead to system UAF (Use-After-Free) issues. Due to the lengthy analysis of the pcrypt_aead01 function call, I'll describe the problem scenario using a simplified model: Suppose there's a user of padata named `user_function` that adheres to the padata requirement of calling `padata_free_shell` after `serial()` has been invoked, as demonstrated in the following code: ```c struct request { struct padata_priv padata; struct completion *done; }; void parallel(struct padata_priv *padata) { do_something(); } void serial(struct padata_priv *padata) { struct request *request = container_of(padata, struct request, padata); complete(request->done); } void user_function() { DECLARE_COMPLETION(done) padata->parallel = parallel; padata->serial = serial; padata_do_parallel(); wait_for_completion(&done); padata_free_shell(); } ``` In the corresponding padata.c file, there's the following code: ```c static void padata_serial_worker(struct work_struct *serial_work) { ... cnt = 0; while (!list_empty(&local_list)) { ... padata->serial(padata); cnt++; } local_bh_enable(); if (refcount_sub_and_test(cnt, &pd->refcnt)) padata_free_pd(pd); } ``` Because of the high system load and the accumulation of unexecuted softirq at this moment, `local_bh_enable()` in padata takes longer to execute than usual. Subsequently, when accessing `pd->refcnt`, `pd` has already been released by `padata_free_shell()`, resulting in a UAF issue with `pd->refcnt`. The fix is straightforward: add `refcount_dec_and_test` before calling `padata_free_pd` in `padata_free_shell`.

linux

In the Linux kernel, the following vulnerability has been resolved: media: imon: fix access to invalid resource for the second interface imon driver probes two USB interfaces, and at the probe of the second interface, the driver assumes blindly that the first interface got bound with the same imon driver. It's usually true, but it's still possible that the first interface is bound with another driver via a malformed descriptor. Then it may lead to a memory corruption, as spotted by syzkaller; imon driver accesses the data from drvdata as struct imon_context object although it's a completely different one that was assigned by another driver. This patch adds a sanity check -- whether the first interface is really bound with the imon driver or not -- for avoiding the problem above at the probe time.

linux

In the Linux kernel, the following vulnerability has been resolved: usb: fix various gadget panics on 10gbps cabling usb_assign_descriptors() is called with 5 parameters, the last 4 of which are the usb_descriptor_header for: full-speed (USB1.1 - 12Mbps [including USB1.0 low-speed @ 1.5Mbps), high-speed (USB2.0 - 480Mbps), super-speed (USB3.0 - 5Gbps), super-speed-plus (USB3.1 - 10Gbps). The differences between full/high/super-speed descriptors are usually substantial (due to changes in the maximum usb block size from 64 to 512 to 1024 bytes and other differences in the specs), while the difference between 5 and 10Gbps descriptors may be as little as nothing (in many cases the same tuning is simply good enough). However if a gadget driver calls usb_assign_descriptors() with a NULL descriptor for super-speed-plus and is then used on a max 10gbps configuration, the kernel will crash with a null pointer dereference, when a 10gbps capable device port + cable + host port combination shows up. (This wouldn't happen if the gadget max-speed was set to 5gbps, but it of course defaults to the maximum, and there's no real reason to artificially limit it) The fix is to simply use the 5gbps descriptor as the 10gbps descriptor, if a 10gbps descriptor wasn't provided. Obviously this won't fix the problem if the 5gbps descriptor is also NULL, but such cases can't be so trivially solved (and any such gadgets are unlikely to be used with USB3 ports any way).

linux

In the Linux kernel, the following vulnerability has been resolved: ethtool: strset: fix message length calculation Outer nest for ETHTOOL_A_STRSET_STRINGSETS is not accounted for. This may result in ETHTOOL_MSG_STRSET_GET producing a warning like: calculated message payload length (684) not sufficient WARNING: CPU: 0 PID: 30967 at net/ethtool/netlink.c:369 ethnl_default_doit+0x87a/0xa20 and a splat. As usually with such warnings three conditions must be met for the warning to trigger: - there must be no skb size rounding up (e.g. reply_size of 684); - string set must be per-device (so that the header gets populated); - the device name must be at least 12 characters long. all in all with current user space it looks like reading priv flags is the only place this could potentially happen. Or with syzbot :)

linux

Stalwart Mail Server is an open-source mail server. Prior to version 0.8.0, attackers who achieved Arbitrary Code Execution as the stalwart-mail user (including web interface admins) can gain complete root access to the system. Usually, system services are run as a separate user (not as root) to isolate an attacker with Arbitrary Code Execution to the current service. Therefore, other system services and the system itself remains protected in case of a successful attack. stalwart-mail runs as a separate user, but it can give itself full privileges again in a simple way, so this protection is practically ineffective. Server admins who handed out the admin credentials to the mail server, but didn't want to hand out complete root access to the system, as well as any attacked user when the attackers gained Arbitrary Code Execution using another vulnerability, may be vulnerable. Version 0.8.0 contains a patch for the issue.

On Windows a directory returned by tempfile.mkdtemp() would not always have permissions set to restrict reading and writing to the temporary directory by other users, instead usually inheriting the correct permissions from the default location. Alternate configurations or users without a profile directory may not have the intended permissions. If you’re not using Windows or haven’t changed the temporary directory location then you aren’t affected by this vulnerability. On other platforms the returned directory is consistently readable and writable only by the current user. This issue was caused by Python not supporting Unix permissions on Windows. The fix adds support for Unix “700” for the mkdir function on Windows which is used by mkdtemp() to ensure the newly created directory has the proper permissions.

In the Linux kernel, the following vulnerability has been resolved: crypto: sun8i-ce - Fix use after free in unprepare sun8i_ce_cipher_unprepare should be called before crypto_finalize_skcipher_request, because client callbacks may immediately free memory, that isn't needed anymore. But it will be used by unprepare after free. Before removing prepare/unprepare callbacks it was handled by crypto engine in crypto_finalize_request. Usually that results in a pointer dereference problem during a in crypto selftest. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000030 Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=000000004716d000 [0000000000000030] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] SMP This problem is detected by KASAN as well. ================================================================== BUG: KASAN: slab-use-after-free in sun8i_ce_cipher_do_one+0x6e8/0xf80 [sun8i_ce] Read of size 8 at addr ffff00000dcdc040 by task 1c15000.crypto-/373 Hardware name: Pine64 PinePhone (1.2) (DT) Call trace: dump_backtrace+0x9c/0x128 show_stack+0x20/0x38 dump_stack_lvl+0x48/0x60 print_report+0xf8/0x5d8 kasan_report+0x90/0xd0 __asan_load8+0x9c/0xc0 sun8i_ce_cipher_do_one+0x6e8/0xf80 [sun8i_ce] crypto_pump_work+0x354/0x620 [crypto_engine] kthread_worker_fn+0x244/0x498 kthread+0x168/0x178 ret_from_fork+0x10/0x20 Allocated by task 379: kasan_save_stack+0x3c/0x68 kasan_set_track+0x2c/0x40 kasan_save_alloc_info+0x24/0x38 __kasan_kmalloc+0xd4/0xd8 __kmalloc+0x74/0x1d0 alg_test_skcipher+0x90/0x1f0 alg_test+0x24c/0x830 cryptomgr_test+0x38/0x60 kthread+0x168/0x178 ret_from_fork+0x10/0x20 Freed by task 379: kasan_save_stack+0x3c/0x68 kasan_set_track+0x2c/0x40 kasan_save_free_info+0x38/0x60 __kasan_slab_free+0x100/0x170 slab_free_freelist_hook+0xd4/0x1e8 __kmem_cache_free+0x15c/0x290 kfree+0x74/0x100 kfree_sensitive+0x80/0xb0 alg_test_skcipher+0x12c/0x1f0 alg_test+0x24c/0x830 cryptomgr_test+0x38/0x60 kthread+0x168/0x178 ret_from_fork+0x10/0x20 The buggy address belongs to the object at ffff00000dcdc000 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 64 bytes inside of freed 256-byte region [ffff00000dcdc000, ffff00000dcdc100)

linux

In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mvm: ensure offloading TID queue exists The resume code path assumes that the TX queue for the offloading TID has been configured. At resume time it then tries to sync the write pointer as it may have been updated by the firmware. In the unusual event that no packets have been send on TID 0, the queue will not have been allocated and this causes a crash. Fix this by ensuring the queue exist at suspend time.

linux

In the Linux kernel, the following vulnerability has been resolved: nouveau: fix instmem race condition around ptr stores Running a lot of VK CTS in parallel against nouveau, once every few hours you might see something like this crash. BUG: kernel NULL pointer dereference, address: 0000000000000008 PGD 8000000114e6e067 P4D 8000000114e6e067 PUD 109046067 PMD 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 7 PID: 53891 Comm: deqp-vk Not tainted 6.8.0-rc6+ #27 Hardware name: Gigabyte Technology Co., Ltd. Z390 I AORUS PRO WIFI/Z390 I AORUS PRO WIFI-CF, BIOS F8 11/05/2021 RIP: 0010:gp100_vmm_pgt_mem+0xe3/0x180 [nouveau] Code: c7 48 01 c8 49 89 45 58 85 d2 0f 84 95 00 00 00 41 0f b7 46 12 49 8b 7e 08 89 da 42 8d 2c f8 48 8b 47 08 41 83 c7 01 48 89 ee <48> 8b 40 08 ff d0 0f 1f 00 49 8b 7e 08 48 89 d9 48 8d 75 04 48 c1 RSP: 0000:ffffac20c5857838 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 00000000004d8001 RCX: 0000000000000001 RDX: 00000000004d8001 RSI: 00000000000006d8 RDI: ffffa07afe332180 RBP: 00000000000006d8 R08: ffffac20c5857ad0 R09: 0000000000ffff10 R10: 0000000000000001 R11: ffffa07af27e2de0 R12: 000000000000001c R13: ffffac20c5857ad0 R14: ffffa07a96fe9040 R15: 000000000000001c FS: 00007fe395eed7c0(0000) GS:ffffa07e2c980000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 000000011febe001 CR4: 00000000003706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ... ? gp100_vmm_pgt_mem+0xe3/0x180 [nouveau] ? gp100_vmm_pgt_mem+0x37/0x180 [nouveau] nvkm_vmm_iter+0x351/0xa20 [nouveau] ? __pfx_nvkm_vmm_ref_ptes+0x10/0x10 [nouveau] ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau] ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau] ? __lock_acquire+0x3ed/0x2170 ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau] nvkm_vmm_ptes_get_map+0xc2/0x100 [nouveau] ? __pfx_nvkm_vmm_ref_ptes+0x10/0x10 [nouveau] ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau] nvkm_vmm_map_locked+0x224/0x3a0 [nouveau] Adding any sort of useful debug usually makes it go away, so I hand wrote the function in a line, and debugged the asm. Every so often pt->memory->ptrs is NULL. This ptrs ptr is set in the nv50_instobj_acquire called from nvkm_kmap. If Thread A and Thread B both get to nv50_instobj_acquire around the same time, and Thread A hits the refcount_set line, and in lockstep thread B succeeds at refcount_inc_not_zero, there is a chance the ptrs value won't have been stored since refcount_set is unordered. Force a memory barrier here, I picked smp_mb, since we want it on all CPUs and it's write followed by a read. v2: use paired smp_rmb/smp_wmb.

linux · debian

An Improper Check for Unusual or Exceptional Conditions vulnerability in the web component of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure (9.x, 22.x) allows a remote unauthenticated attacker to send specially crafted requests in-order-to cause service disruptions.