Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: xdp, net: Fix use-after-free in bpf_xdp_link_release The problem occurs between dev_get_by_index() and dev_xdp_attach_link(). At this point, dev_xdp_uninstall() is called. Then xdp link will not be detached automatically when dev is released. But link->dev already points to dev, when xdp link is released, dev will still be accessed, but dev has been released. dev_get_by_index() | link->dev = dev | | rtnl_lock() | unregister_netdevice_many() | dev_xdp_uninstall() | rtnl_unlock() rtnl_lock(); | dev_xdp_attach_link() | rtnl_unlock(); | | netdev_run_todo() // dev released bpf_xdp_link_release() | /* access dev. | use-after-free */ | [ 45.966867] BUG: KASAN: use-after-free in bpf_xdp_link_release+0x3b8/0x3d0 [ 45.967619] Read of size 8 at addr ffff00000f9980c8 by task a.out/732 [ 45.968297] [ 45.968502] CPU: 1 PID: 732 Comm: a.out Not tainted 5.13.0+ #22 [ 45.969222] Hardware name: linux,dummy-virt (DT) [ 45.969795] Call trace: [ 45.970106] dump_backtrace+0x0/0x4c8 [ 45.970564] show_stack+0x30/0x40 [ 45.970981] dump_stack_lvl+0x120/0x18c [ 45.971470] print_address_description.constprop.0+0x74/0x30c [ 45.972182] kasan_report+0x1e8/0x200 [ 45.972659] __asan_report_load8_noabort+0x2c/0x50 [ 45.973273] bpf_xdp_link_release+0x3b8/0x3d0 [ 45.973834] bpf_link_free+0xd0/0x188 [ 45.974315] bpf_link_put+0x1d0/0x218 [ 45.974790] bpf_link_release+0x3c/0x58 [ 45.975291] __fput+0x20c/0x7e8 [ 45.975706] ____fput+0x24/0x30 [ 45.976117] task_work_run+0x104/0x258 [ 45.976609] do_notify_resume+0x894/0xaf8 [ 45.977121] work_pending+0xc/0x328 [ 45.977575] [ 45.977775] The buggy address belongs to the page: [ 45.978369] page:fffffc00003e6600 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4f998 [ 45.979522] flags: 0x7fffe0000000000(node=0|zone=0|lastcpupid=0x3ffff) [ 45.980349] raw: 07fffe0000000000 fffffc00003e6708 ffff0000dac3c010 0000000000000000 [ 45.981309] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 [ 45.982259] page dumped because: kasan: bad access detected [ 45.982948] [ 45.983153] Memory state around the buggy address: [ 45.983753] ffff00000f997f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 45.984645] ffff00000f998000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 45.985533] >ffff00000f998080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 45.986419] ^ [ 45.987112] ffff00000f998100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 45.988006] ffff00000f998180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 45.988895] ================================================================== [ 45.989773] Disabling lock debugging due to kernel taint [ 45.990552] Kernel panic - not syncing: panic_on_warn set ... [ 45.991166] CPU: 1 PID: 732 Comm: a.out Tainted: G B 5.13.0+ #22 [ 45.991929] Hardware name: linux,dummy-virt (DT) [ 45.992448] Call trace: [ 45.992753] dump_backtrace+0x0/0x4c8 [ 45.993208] show_stack+0x30/0x40 [ 45.993627] dump_stack_lvl+0x120/0x18c [ 45.994113] dump_stack+0x1c/0x34 [ 45.994530] panic+0x3a4/0x7d8 [ 45.994930] end_report+0x194/0x198 [ 45.995380] kasan_report+0x134/0x200 [ 45.995850] __asan_report_load8_noabort+0x2c/0x50 [ 45.996453] bpf_xdp_link_release+0x3b8/0x3d0 [ 45.997007] bpf_link_free+0xd0/0x188 [ 45.997474] bpf_link_put+0x1d0/0x218 [ 45.997942] bpf_link_release+0x3c/0x58 [ 45.998429] __fput+0x20c/0x7e8 [ 45.998833] ____fput+0x24/0x30 [ 45.999247] task_work_run+0x104/0x258 [ 45.999731] do_notify_resume+0x894/0xaf8 [ 46.000236] work_pending ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Fix potential memory leak on unlikely error case If skb_linearize is needed and fails we could leak a msg on the error handling. To fix ensure we kfree the msg block before returning error. Found during code review.Show less

In the Linux kernel, the following vulnerability has been resolved: net: fix uninit-value in caif_seqpkt_sendmsg When nr_segs equal to zero in iovec_from_user, the object msg->msg_iter.iov is uninit stack memory in caif_seqpkt_sendmsg which is defined in ___sys_sendmsg. So we cann't just judge msg->msg_iter.iov->base directlly. We can use nr_segs to judge msg in caif_seqpkt_sendmsg whether has data buffers. ===================================================== BUG: KMSAN: uninit-value in caif_seqpkt_sendmsg+0x693/0xf60 net/caif/caif_socket.c:542 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 caif_seqpkt_sendmsg+0x693/0xf60 net/caif/caif_socket.c:542 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2343 ___sys_sendmsg net/socket.c:2397 [inline] __sys_sendmmsg+0x808/0xc90 net/socket.c:2480 __compat_sys_sendmmsg net/compat.c:656 [inline]Show less

In the Linux kernel, the following vulnerability has been resolved: KVM: PPC: Fix kvm_arch_vcpu_ioctl vcpu_load leak vcpu_put is not called if the user copy fails. This can result in preempt notifier corruption and crashes, among other issues.Show less

In the Linux kernel, the following vulnerability has been resolved: net: sched: fix memory leak in tcindex_partial_destroy_work Syzbot reported memory leak in tcindex_set_parms(). The problem was in non-freed perfect hash in tcindex_partial_destroy_work(). In tcindex_set_parms() new tcindex_data is allocated and some fields from old one are copied to new one, but not the perfect hash. Since tcindex_partial_destroy_work() is the destroy function for old tcindex_data, we need to free perfect hash to avoid memory leak.Show less

In the Linux kernel, the following vulnerability has been resolved: netrom: Decrease sock refcount when sock timers expire Commit 63346650c1a9 ("netrom: switch to sock timer API") switched to use sock timer API. It replaces mod_timer() by sk_reset_timer(), and del_timer() by sk_stop_timer(). Function sk_reset_timer() will increase the refcount of sock if it is called on an inactive timer, hence, in case the timer expires, we need to decrease the refcount ourselves in the handler, otherwise, the sock refcount will be unbalanced and the sock will never be freed.Show less

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_skbmod: Skip non-Ethernet packets Currently tcf_skbmod_act() assumes that packets use Ethernet as their L2 protocol, which is not always the case. As an example, for CAN devices: $ ip link add dev vcan0 type vcan $ ip link set up vcan0 $ tc qdisc add dev vcan0 root handle 1: htb $ tc filter add dev vcan0 parent 1: protocol ip prio 10 \ matchall action skbmod swap mac Doing the above silently corrupts all the packets. Do not perform skbmod actions for non-Ethernet packets.Show less

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix memleak in io_init_wq_offload() I got memory leak report when doing fuzz test: BUG: memory leak unreferenced object 0xffff888107310a80 (size 96): comm "syz-executor.6", pid 4610, jiffies 4295140240 (age 20.135s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... backtrace: [<000000001974933b>] kmalloc include/linux/slab.h:591 [inline] [<000000001974933b>] kzalloc include/linux/slab.h:721 [inline] [<000000001974933b>] io_init_wq_offload fs/io_uring.c:7920 [inline] [<000000001974933b>] io_uring_alloc_task_context+0x466/0x640 fs/io_uring.c:7955 [<0000000039d0800d>] __io_uring_add_tctx_node+0x256/0x360 fs/io_uring.c:9016 [<000000008482e78c>] io_uring_add_tctx_node fs/io_uring.c:9052 [inline] [<000000008482e78c>] __do_sys_io_uring_enter fs/io_uring.c:9354 [inline] [<000000008482e78c>] __se_sys_io_uring_enter fs/io_uring.c:9301 [inline] [<000000008482e78c>] __x64_sys_io_uring_enter+0xabc/0xc20 fs/io_uring.c:9301 [<00000000b875f18f>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<00000000b875f18f>] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 [<000000006b0a8484>] entry_SYSCALL_64_after_hwframe+0x44/0xae CPU0 CPU1 io_uring_enter io_uring_enter io_uring_add_tctx_node io_uring_add_tctx_node __io_uring_add_tctx_node __io_uring_add_tctx_node io_uring_alloc_task_context io_uring_alloc_task_context io_init_wq_offload io_init_wq_offload hash = kzalloc hash = kzalloc ctx->hash_map = hash ctx->hash_map = hash <- one of the hash is leaked When calling io_uring_enter() in parallel, the 'hash_map' will be leaked, add uring_lock to protect 'hash_map'.Show less

In the Linux kernel, the following vulnerability has been resolved: ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions While running the self-tests on a KASAN enabled kernel, I observed a slab-out-of-bounds splat very similar to the one reported in commit 821bbf79fe46 ("ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions"). We additionally need to take care of fib6_metrics initialization failure when the caller provides an nh. The fix is similar, explicitly free the route instead of calling fib6_info_release on a half-initialized object.Show less

In the Linux kernel, the following vulnerability has been resolved: scsi: target: Fix NULL dereference on XCOPY completion CPU affinity control added with commit 39ae3edda325 ("scsi: target: core: Make completion affinity configurable") makes target_complete_cmd() queue work on a CPU based on se_tpg->se_tpg_wwn->cmd_compl_affinity state. LIO's EXTENDED COPY worker is a special case in that read/write cmds are dispatched using the global xcopy_pt_tpg, which carries a NULL se_tpg_wwn pointer following initialization in target_xcopy_setup_pt(). The NULL xcopy_pt_tpg->se_tpg_wwn pointer is dereferenced on completion of any EXTENDED COPY initiated read/write cmds. E.g using the libiscsi SCSI.ExtendedCopy.Simple test: BUG: kernel NULL pointer dereference, address: 00000000000001a8 RIP: 0010:target_complete_cmd+0x9d/0x130 [target_core_mod] Call Trace: fd_execute_rw+0x148/0x42a [target_core_file] ? __dynamic_pr_debug+0xa7/0xe0 ? target_check_reservation+0x5b/0x940 [target_core_mod] __target_execute_cmd+0x1e/0x90 [target_core_mod] transport_generic_new_cmd+0x17c/0x330 [target_core_mod] target_xcopy_issue_pt_cmd+0x9/0x60 [target_core_mod] target_xcopy_read_source.isra.7+0x10b/0x1b0 [target_core_mod] ? target_check_fua+0x40/0x40 [target_core_mod] ? transport_complete_task_attr+0x130/0x130 [target_core_mod] target_xcopy_do_work+0x61f/0xc00 [target_core_mod] This fix makes target_complete_cmd() queue work on se_cmd->cpuid if se_tpg_wwn is NULL.Show less

In the Linux kernel, the following vulnerability has been resolved: ACPI: fix NULL pointer dereference Commit 71f642833284 ("ACPI: utils: Fix reference counting in for_each_acpi_dev_match()") started doing "acpi_dev_put()" on a pointer that was possibly NULL. That fails miserably, because that helper inline function is not set up to handle that case. Just make acpi_dev_put() silently accept a NULL pointer, rather than calling down to put_device() with an invalid offset off that NULL pointer.Show less

In the Linux kernel, the following vulnerability has been resolved: media: ngene: Fix out-of-bounds bug in ngene_command_config_free_buf() Fix an 11-year old bug in ngene_command_config_free_buf() while addressing the following warnings caught with -Warray-bounds: arch/alpha/include/asm/string.h:22:16: warning: '__builtin_memcpy' offset [12, 16] from the object at 'com' is out of the bounds of referenced subobject 'config' with type 'unsigned char' at offset 10 [-Warray-bounds] arch/x86/include/asm/string_32.h:182:25: warning: '__builtin_memcpy' offset [12, 16] from the object at 'com' is out of the bounds of referenced subobject 'config' with type 'unsigned char' at offset 10 [-Warray-bounds] The problem is that the original code is trying to copy 6 bytes of data into a one-byte size member _config_ of the wrong structue FW_CONFIGURE_BUFFERS, in a single call to memcpy(). This causes a legitimate compiler warning because memcpy() overruns the length of &com.cmd.ConfigureBuffers.config. It seems that the right structure is FW_CONFIGURE_FREE_BUFFERS, instead, because it contains 6 more members apart from the header _hdr_. Also, the name of the function ngene_command_config_free_buf() suggests that the actual intention is to ConfigureFreeBuffers, instead of ConfigureBuffers (which takes place in the function ngene_command_config_buf(), above). Fix this by enclosing those 6 members of struct FW_CONFIGURE_FREE_BUFFERS into new struct config, and use &com.cmd.ConfigureFreeBuffers.config as the destination address, instead of &com.cmd.ConfigureBuffers.config, when calling memcpy(). This also helps with the ongoing efforts to globally enable -Warray-bounds and get us closer to being able to tighten the FORTIFY_SOURCE routines on memcpy().Show less

In the Linux kernel, the following vulnerability has been resolved: driver core: auxiliary bus: Fix memory leak when driver_register() fail If driver_register() returns with error we need to free the memory allocated for auxdrv->driver.name before returning from __auxiliary_driver_register()Show less

In the Linux kernel, the following vulnerability has been resolved: bus: mhi: core: Validate channel ID when processing command completions MHI reads the channel ID from the event ring element sent by the device which can be any value between 0 and 255. In order to prevent any out of bound accesses, add a check against the maximum number of channels supported by the controller and those channels not configured yet so as to skip processing of that event ring element.Show less

In the Linux kernel, the following vulnerability has been resolved: isdn: mISDN: netjet: Fix crash in nj_probe: 'nj_setup' in netjet.c might fail with -EIO and in this case 'card->irq' is initialized and is bigger than zero. A subsequent call to 'nj_release' will free the irq that has not been requested. Fix this bug by deleting the previous assignment to 'card->irq' and just keep the assignment before 'request_irq'. The KASAN's log reveals it: [ 3.354615 ] WARNING: CPU: 0 PID: 1 at kernel/irq/manage.c:1826 free_irq+0x100/0x480 [ 3.355112 ] Modules linked in: [ 3.355310 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.355816 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 3.356552 ] RIP: 0010:free_irq+0x100/0x480 [ 3.356820 ] Code: 6e 08 74 6f 4d 89 f4 e8 5e ac 09 00 4d 8b 74 24 18 4d 85 f6 75 e3 e8 4f ac 09 00 8b 75 c8 48 c7 c7 78 c1 2e 85 e8 e0 cf f5 ff <0f> 0b 48 8b 75 c0 4c 89 ff e8 72 33 0b 03 48 8b 43 40 4c 8b a0 80 [ 3.358012 ] RSP: 0000:ffffc90000017b48 EFLAGS: 00010082 [ 3.358357 ] RAX: 0000000000000000 RBX: ffff888104dc8000 RCX: 0000000000000000 [ 3.358814 ] RDX: ffff8881003c8000 RSI: ffffffff8124a9e6 RDI: 00000000ffffffff [ 3.359272 ] RBP: ffffc90000017b88 R08: 0000000000000000 R09: 0000000000000000 [ 3.359732 ] R10: ffffc900000179f0 R11: 0000000000001d04 R12: 0000000000000000 [ 3.360195 ] R13: ffff888107dc6000 R14: ffff888107dc6928 R15: ffff888104dc80a8 [ 3.360652 ] FS: 0000000000000000(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 [ 3.361170 ] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.361538 ] CR2: 0000000000000000 CR3: 000000000582e000 CR4: 00000000000006f0 [ 3.362003 ] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3.362175 ] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3.362175 ] Call Trace: [ 3.362175 ] nj_release+0x51/0x1e0 [ 3.362175 ] nj_probe+0x450/0x950 [ 3.362175 ] ? pci_device_remove+0x110/0x110 [ 3.362175 ] local_pci_probe+0x45/0xa0 [ 3.362175 ] pci_device_probe+0x12b/0x1d0 [ 3.362175 ] really_probe+0x2a9/0x610 [ 3.362175 ] driver_probe_device+0x90/0x1d0 [ 3.362175 ] ? mutex_lock_nested+0x1b/0x20 [ 3.362175 ] device_driver_attach+0x68/0x70 [ 3.362175 ] __driver_attach+0x124/0x1b0 [ 3.362175 ] ? device_driver_attach+0x70/0x70 [ 3.362175 ] bus_for_each_dev+0xbb/0x110 [ 3.362175 ] ? rdinit_setup+0x45/0x45 [ 3.362175 ] driver_attach+0x27/0x30 [ 3.362175 ] bus_add_driver+0x1eb/0x2a0 [ 3.362175 ] driver_register+0xa9/0x180 [ 3.362175 ] __pci_register_driver+0x82/0x90 [ 3.362175 ] ? w6692_init+0x38/0x38 [ 3.362175 ] nj_init+0x36/0x38 [ 3.362175 ] do_one_initcall+0x7f/0x3d0 [ 3.362175 ] ? rdinit_setup+0x45/0x45 [ 3.362175 ] ? rcu_read_lock_sched_held+0x4f/0x80 [ 3.362175 ] kernel_init_freeable+0x2aa/0x301 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] kernel_init+0x18/0x190 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] ? rest_init+0x2c0/0x2c0 [ 3.362175 ] ret_from_fork+0x1f/0x30 [ 3.362175 ] Kernel panic - not syncing: panic_on_warn set ... [ 3.362175 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.362175 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [ 3.362175 ] Call Trace: [ 3.362175 ] dump_stack+0xba/0xf5 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] panic+0x15a/0x3f2 [ 3.362175 ] ? __warn+0xf2/0x150 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] __warn+0x108/0x150 [ 3.362175 ] ? free_irq+0x100/0x480 [ 3.362175 ] report_bug+0x119/0x1c0 [ 3.362175 ] handle_bug+0x3b/0x80 [ 3.362175 ] exc_invalid_op+0x18/0x70 [ 3.362175 ] asm_exc_invalid_op+0x12/0x20 [ 3.362175 ] RIP: 0010:free_irq+0x100 ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: net:sfc: fix non-freed irq in legacy irq mode SFC driver can be configured via modparam to work using MSI-X, MSI or legacy IRQ interrupts. In the last one, the interrupt was not properly released on module remove. It was not freed because the flag irqs_hooked was not set during initialization in the case of using legacy IRQ. Example of (trimmed) trace during module remove without this fix: remove_proc_entry: removing non-empty directory 'irq/125', leaking at least '0000:3b:00.1' WARNING: CPU: 39 PID: 3658 at fs/proc/generic.c:715 remove_proc_entry+0x15c/0x170 ...trimmed... Call Trace: unregister_irq_proc+0xe3/0x100 free_desc+0x29/0x70 irq_free_descs+0x47/0x70 mp_unmap_irq+0x58/0x60 acpi_unregister_gsi_ioapic+0x2a/0x40 acpi_pci_irq_disable+0x78/0xb0 pci_disable_device+0xd1/0x100 efx_pci_remove+0xa1/0x1e0 [sfc] pci_device_remove+0x38/0xa0 __device_release_driver+0x177/0x230 driver_detach+0xcb/0x110 bus_remove_driver+0x58/0xd0 pci_unregister_driver+0x2a/0xb0 efx_exit_module+0x24/0xf40 [sfc] __do_sys_delete_module.constprop.0+0x171/0x280 ? exit_to_user_mode_prepare+0x83/0x1d0 do_syscall_64+0x3d/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9f9385800b ...trimmed...Show less

In the Linux kernel, the following vulnerability has been resolved: spi: bcm2835: Fix out-of-bounds access with more than 4 slaves Commit 571e31fa60b3 ("spi: bcm2835: Cache CS register value for ->prepare_message()") limited the number of slaves to 3 at compile-time. The limitation was necessitated by a statically-sized array prepare_cs[] in the driver private data which contains a per-slave register value. The commit sought to enforce the limitation at run-time by setting the controller's num_chipselect to 3: Slaves with a higher chipselect are rejected by spi_add_device(). However the commit neglected that num_chipselect only limits the number of *native* chipselects. If GPIO chipselects are specified in the device tree for more than 3 slaves, num_chipselect is silently raised by of_spi_get_gpio_numbers() and the result are out-of-bounds accesses to the statically-sized array prepare_cs[]. As a bandaid fix which is backportable to stable, raise the number of allowed slaves to 24 (which "ought to be enough for anybody"), enforce the limitation on slave ->setup and revert num_chipselect to 3 (which is the number of native chipselects supported by the controller). An upcoming for-next commit will allow an arbitrary number of slaves.Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: seq: Fix race of snd_seq_timer_open() The timer instance per queue is exclusive, and snd_seq_timer_open() should have managed the concurrent accesses. It looks as if it's checking the already existing timer instance at the beginning, but it's not right, because there is no protection, hence any later concurrent call of snd_seq_timer_open() may override the timer instance easily. This may result in UAF, as the leftover timer instance can keep running while the queue itself gets closed, as spotted by syzkaller recently. For avoiding the race, add a proper check at the assignment of tmr->timeri again, and return -EBUSY if it's been already registered.Show less

In the Linux kernel, the following vulnerability has been resolved: drm: Fix use-after-free read in drm_getunique() There is a time-of-check-to-time-of-use error in drm_getunique() due to retrieving file_priv->master prior to locking the device's master mutex. An example can be seen in the crash report of the use-after-free error found by Syzbot: https://syzkaller.appspot.com/bug?id=148d2f1dfac64af52ffd27b661981a540724f803 In the report, the master pointer was used after being freed. This is because another process had acquired the device's master mutex in drm_setmaster_ioctl(), then overwrote fpriv->master in drm_new_set_master(). The old value of fpriv->master was subsequently freed before the mutex was unlocked. To fix this, we lock the device's master mutex before retrieving the pointer from from fpriv->master. This patch passes the Syzbot reproducer test.Show less

In the Linux kernel, the following vulnerability has been resolved: usb: misc: brcmstb-usb-pinmap: check return value after calling platform_get_resource() It will cause null-ptr-deref if platform_get_resource() returns NULL, we need check the return value.Show less