Linux

In the Linux kernel, the following vulnerability has been resolved: binder: fix UAF of ref->proc caused by race condition A transaction of type BINDER_TYPE_WEAK_HANDLE can fail to increment the reference for a node. In this case, the target proc normally releases the failed reference upon close as expected. However, if the target is dying in parallel the call will race with binder_deferred_release(), so the target could have released all of its references by now leaving the cleanup of the new failed reference unhandled. The transaction then ends and the target proc gets released making the ref->proc now a dangling pointer. Later on, ref->node is closed and we attempt to take spin_lock(&ref->proc->inner_lock), which leads to the use-after-free bug reported below. Let's fix this by cleaning up the failed reference on the spot instead of relying on the target to do so. ================================================================== BUG: KASAN: use-after-free in _raw_spin_lock+0xa8/0x150 Write of size 4 at addr ffff5ca207094238 by task kworker/1:0/590 CPU: 1 PID: 590 Comm: kworker/1:0 Not tainted 5.19.0-rc8 #10 Hardware name: linux,dummy-virt (DT) Workqueue: events binder_deferred_func Call trace: dump_backtrace.part.0+0x1d0/0x1e0 show_stack+0x18/0x70 dump_stack_lvl+0x68/0x84 print_report+0x2e4/0x61c kasan_report+0xa4/0x110 kasan_check_range+0xfc/0x1a4 __kasan_check_write+0x3c/0x50 _raw_spin_lock+0xa8/0x150 binder_deferred_func+0x5e0/0x9b0 process_one_work+0x38c/0x5f0 worker_thread+0x9c/0x694 kthread+0x188/0x190 ret_from_fork+0x10/0x20Show less

In the Linux kernel, the following vulnerability has been resolved: cifs: fix small mempool leak in SMB2_negotiate() In some cases of failure (dialect mismatches) in SMB2_negotiate(), after the request is sent, the checks would return -EIO when they should be rather setting rc = -EIO and jumping to neg_exit to free the response buffer from mempool.Show less

In the Linux kernel, the following vulnerability has been resolved: media: mceusb: Use new usb_control_msg_*() routines Automatic kernel fuzzing led to a WARN about invalid pipe direction in the mceusb driver: ------------[ cut here ]------------ usb 6-1: BOGUS control dir, pipe 80000380 doesn't match bRequestType 40 WARNING: CPU: 0 PID: 2465 at drivers/usb/core/urb.c:410 usb_submit_urb+0x1326/0x1820 drivers/usb/core/urb.c:410 Modules linked in: CPU: 0 PID: 2465 Comm: kworker/0:2 Not tainted 5.19.0-rc4-00208-g69cb6c6556ad #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: usb_hub_wq hub_event RIP: 0010:usb_submit_urb+0x1326/0x1820 drivers/usb/core/urb.c:410 Code: 7c 24 40 e8 ac 23 91 fd 48 8b 7c 24 40 e8 b2 70 1b ff 45 89 e8 44 89 f1 4c 89 e2 48 89 c6 48 c7 c7 a0 30 a9 86 e8 48 07 11 02 <0f> 0b e9 1c f0 ff ff e8 7e 23 91 fd 0f b6 1d 63 22 83 05 31 ff 41 RSP: 0018:ffffc900032becf0 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff8881100f3058 RCX: 0000000000000000 RDX: ffffc90004961000 RSI: ffff888114c6d580 RDI: fffff52000657d90 RBP: ffff888105ad90f0 R08: ffffffff812c3638 R09: 0000000000000000 R10: 0000000000000005 R11: ffffed1023504ef1 R12: ffff888105ad9000 R13: 0000000000000040 R14: 0000000080000380 R15: ffff88810ba96500 FS: 0000000000000000(0000) GS:ffff88811a800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe810bda58 CR3: 000000010b720000 CR4: 0000000000350ef0 Call Trace: <TASK> usb_start_wait_urb+0x101/0x4c0 drivers/usb/core/message.c:58 usb_internal_control_msg drivers/usb/core/message.c:102 [inline] usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:153 mceusb_gen1_init drivers/media/rc/mceusb.c:1431 [inline] mceusb_dev_probe+0x258e/0x33f0 drivers/media/rc/mceusb.c:1807 The reason for the warning is clear enough; the driver sends an unusual read request on endpoint 0 but does not set the USB_DIR_IN bit in the bRequestType field. More importantly, the whole situation can be avoided and the driver simplified by converting it over to the relatively new usb_control_msg_recv() and usb_control_msg_send() routines. That's what this fix does.Show less

In the Linux kernel, the following vulnerability has been resolved: USB: core: Prevent nested device-reset calls Automatic kernel fuzzing revealed a recursive locking violation in usb-storage: ============================================ WARNING: possible recursive locking detected 5.18.0 #3 Not tainted -------------------------------------------- kworker/1:3/1205 is trying to acquire lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 but task is already holding lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 ... stack backtrace: CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2988 [inline] check_deadlock kernel/locking/lockdep.c:3031 [inline] validate_chain kernel/locking/lockdep.c:3816 [inline] __lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747 usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109 r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622 usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:545 [inline] device_remove+0x11f/0x170 drivers/base/dd.c:537 __device_release_driver drivers/base/dd.c:1222 [inline] device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248 usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627 usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118 usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114 This turned out not to be an error in usb-storage but rather a nested device reset attempt. That is, as the rtl8712 driver was being unbound from a composite device in preparation for an unrelated USB reset (that driver does not have pre_reset or post_reset callbacks), its ->remove routine called usb_reset_device() -- thus nesting one reset call within another. Performing a reset as part of disconnect processing is a questionable practice at best. However, the bug report points out that the USB core does not have any protection against nested resets. Adding a reset_in_progress flag and testing it will prevent such errors in the future.Show less

In the Linux kernel, the following vulnerability has been resolved: dma-buf/dma-resv: check if the new fence is really later Previously when we added a fence to a dma_resv object we always assumed the the newer than all the existing fences. With Jason's work to add an UAPI to explicit export/import that's not necessary the case any more. So without this check we would allow userspace to force the kernel into an use after free error. Since the change is very small and defensive it's probably a good idea to backport this to stable kernels as well just in case others are using the dma_resv object in the same way.Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: Fix UAF in ieee80211_scan_rx() ieee80211_scan_rx() tries to access scan_req->flags after a null check, but a UAF is observed when the scan is completed and __ieee80211_scan_completed() executes, which then calls cfg80211_scan_done() leading to the freeing of scan_req. Since scan_req is rcu_dereference()'d, prevent the racing in __ieee80211_scan_completed() by ensuring that from mac80211's POV it is no longer accessed from an RCU read critical section before we call cfg80211_scan_done().Show less

In the Linux kernel, the following vulnerability has been resolved: gpio: virtuser: fix potential out-of-bound write If the caller wrote more characters, count is truncated to the max available space in "simple_write_to_buffer". Check that the input size does not exceed the buffer size. Write a zero termination afterwards.Show less

In the Linux kernel, the following vulnerability has been resolved: spi-rockchip: Fix register out of bounds access Do not write native chip select stuff for GPIO chip selects. GPIOs can be numbered much higher than native CS. Also, it makes no sense.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Increase block_sequence array size [Why] It's possible to generate more than 50 steps in hwss_build_fast_sequence, for example with a 6-pipe asic where all pipes are in one MPC chain. This overflows the block_sequence buffer and corrupts block_sequence_steps, causing a crash. [How] Expand block_sequence to 100 items. A naive upper bound on the possible number of steps for a 6-pipe asic, ignoring the potential for steps to be mutually exclusive, is 91 with current code, therefore 100 is sufficient.Show less

In the Linux kernel, the following vulnerability has been resolved: crypto: algif_hash - fix double free in hash_accept If accept(2) is called on socket type algif_hash with MSG_MORE flag set and crypto_ahash_import fails, sk2 is freed. However, it is also freed in af_alg_release, leading to slab-use-after-free error.Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Fix race of buffer access at PCM OSS layer The PCM OSS layer tries to clear the buffer with the silence data at initialization (or reconfiguration) of a stream with the explicit call of snd_pcm_format_set_silence() with runtime->dma_area. But this may lead to a UAF because the accessed runtime->dma_area might be freed concurrently, as it's performed outside the PCM ops. For avoiding it, move the code into the PCM core and perform it inside the buffer access lock, so that it won't be changed during the operation.Show less

In the Linux kernel, the following vulnerability has been resolved: platform/x86: dell-wmi-sysman: Avoid buffer overflow in current_password_store() If the 'buf' array received from the user contains an empty string, the 'length' variable will be zero. Accessing the 'buf' array element with index 'length - 1' will result in a buffer overflow. Add a check for an empty string. Found by Linux Verification Center (linuxtesting.org) with SVACE.Show less

In the Linux kernel, the following vulnerability has been resolved: alloc_tag: allocate percpu counters for module tags dynamically When a module gets unloaded it checks whether any of its tags are still in use and if so, we keep the memory containing module's allocation tags alive until all tags are unused. However percpu counters referenced by the tags are freed by free_module(). This will lead to UAF if the memory allocated by a module is accessed after module was unloaded. To fix this we allocate percpu counters for module allocation tags dynamically and we keep it alive for tags which are still in use after module unloading. This also removes the requirement of a larger PERCPU_MODULE_RESERVE when memory allocation profiling is enabled because percpu memory for counters does not need to be reserved anymore.Show less

In the Linux kernel, the following vulnerability has been resolved: scsi: target: iscsi: Fix timeout on deleted connection NOPIN response timer may expire on a deleted connection and crash with such logs: Did not receive response to NOPIN on CID: 0, failing connection for I_T Nexus (null),i,0x00023d000125,iqn.2017-01.com.iscsi.target,t,0x3d BUG: Kernel NULL pointer dereference on read at 0x00000000 NIP strlcpy+0x8/0xb0 LR iscsit_fill_cxn_timeout_err_stats+0x5c/0xc0 [iscsi_target_mod] Call Trace: iscsit_handle_nopin_response_timeout+0xfc/0x120 [iscsi_target_mod] call_timer_fn+0x58/0x1f0 run_timer_softirq+0x740/0x860 __do_softirq+0x16c/0x420 irq_exit+0x188/0x1c0 timer_interrupt+0x184/0x410 That is because nopin response timer may be re-started on nopin timer expiration. Stop nopin timer before stopping the nopin response timer to be sure that no one of them will be re-started.Show less

In the Linux kernel, the following vulnerability has been resolved: vhost-scsi: protect vq->log_used with vq->mutex The vhost-scsi completion path may access vq->log_base when vq->log_used is already set to false. vhost-thread QEMU-thread vhost_scsi_complete_cmd_work() -> vhost_add_used() -> vhost_add_used_n() if (unlikely(vq->log_used)) QEMU disables vq->log_used via VHOST_SET_VRING_ADDR. mutex_lock(&vq->mutex); vq->log_used = false now! mutex_unlock(&vq->mutex); QEMU gfree(vq->log_base) log_used() -> log_write(vq->log_base) Assuming the VMM is QEMU. The vq->log_base is from QEMU userpace and can be reclaimed via gfree(). As a result, this causes invalid memory writes to QEMU userspace. The control queue path has the same issue.Show less

In the Linux kernel, the following vulnerability has been resolved: libnvdimm/labels: Fix divide error in nd_label_data_init() If a faulty CXL memory device returns a broken zero LSA size in its memory device information (Identify Memory Device (Opcode 4000h), CXL spec. 3.1, 8.2.9.9.1.1), a divide error occurs in the libnvdimm driver: Oops: divide error: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:nd_label_data_init+0x10e/0x800 [libnvdimm] Code and flow: 1) CXL Command 4000h returns LSA size = 0 2) config_size is assigned to zero LSA size (CXL pmem driver): drivers/cxl/pmem.c: .config_size = mds->lsa_size, 3) max_xfer is set to zero (nvdimm driver): drivers/nvdimm/label.c: max_xfer = min_t(size_t, ndd->nsarea.max_xfer, config_size); 4) A subsequent DIV_ROUND_UP() causes a division by zero: drivers/nvdimm/label.c: /* Make our initial read size a multiple of max_xfer size */ drivers/nvdimm/label.c: read_size = min(DIV_ROUND_UP(read_size, max_xfer) * max_xfer, drivers/nvdimm/label.c- config_size); Fix this by checking the config size parameter by extending an existing check.Show less

In the Linux kernel, the following vulnerability has been resolved: x86/mm: Check return value from memblock_phys_alloc_range() At least with CONFIG_PHYSICAL_START=0x100000, if there is < 4 MiB of contiguous free memory available at this point, the kernel will crash and burn because memblock_phys_alloc_range() returns 0 on failure, which leads memblock_phys_free() to throw the first 4 MiB of physical memory to the wolves. At a minimum it should fail gracefully with a meaningful diagnostic, but in fact everything seems to work fine without the weird reserve allocation.Show less

In the Linux kernel, the following vulnerability has been resolved: ASoC: sma1307: Add NULL check in sma1307_setting_loaded() All varibale allocated by kzalloc and devm_kzalloc could be NULL. Multiple pointer checks and their cleanup are added. This issue is found by our static analysis toolShow less

In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: pci-epf-test: Fix double free that causes kernel to oops Fix a kernel oops found while testing the stm32_pcie Endpoint driver with handling of PERST# deassertion: During EP initialization, pci_epf_test_alloc_space() allocates all BARs, which are further freed if epc_set_bar() fails (for instance, due to no free inbound window). However, when pci_epc_set_bar() fails, the error path: pci_epc_set_bar() -> pci_epf_free_space() does not clear the previous assignment to epf_test->reg[bar]. Then, if the host reboots, the PERST# deassertion restarts the BAR allocation sequence with the same allocation failure (no free inbound window), creating a double free situation since epf_test->reg[bar] was deallocated and is still non-NULL. Thus, make sure that pci_epf_alloc_space() and pci_epf_free_space() invocations are symmetric, and as such, set epf_test->reg[bar] to NULL when memory is freed. [kwilczynski: commit log]Show less

In the Linux kernel, the following vulnerability has been resolved: crypto: lzo - Fix compression buffer overrun Unlike the decompression code, the compression code in LZO never checked for output overruns. It instead assumes that the caller always provides enough buffer space, disregarding the buffer length provided by the caller. Add a safe compression interface that checks for the end of buffer before each write. Use the safe interface in crypto/lzo.Show less