Linux

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: free queued packets when closing socket As reported by syzbot [1], there is a memory leak while closing the socket. We partially solved this issue with commit ac03046ece2b ("vsock/virtio: free packets during the socket release"), but we forgot to drain the RX queue when the socket is definitely closed by the scheduled work. To avoid future issues, let's use the new virtio_transport_remove_sock() to drain the RX queue before removing the socket from the af_vsock lists calling vsock_remove_sock(). [1] https://syzkaller.appspot.com/bug?extid=24452624fc4c571eedd9Show less

In the Linux kernel, the following vulnerability has been resolved: net: marvell: prestera: fix port event handling on init For some reason there might be a crash during ports creation if port events are handling at the same time because fw may send initial port event with down state. The crash points to cancel_delayed_work() which is called when port went is down. Currently I did not find out the real cause of the issue, so fixed it by cancel port stats work only if previous port's state was up & runnig. The following is the crash which can be triggered: [ 28.311104] Unable to handle kernel paging request at virtual address 000071775f776600 [ 28.319097] Mem abort info: [ 28.321914] ESR = 0x96000004 [ 28.324996] EC = 0x25: DABT (current EL), IL = 32 bits [ 28.330350] SET = 0, FnV = 0 [ 28.333430] EA = 0, S1PTW = 0 [ 28.336597] Data abort info: [ 28.339499] ISV = 0, ISS = 0x00000004 [ 28.343362] CM = 0, WnR = 0 [ 28.346354] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000100bf7000 [ 28.352842] [000071775f776600] pgd=0000000000000000, p4d=0000000000000000 [ 28.359695] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 28.365310] Modules linked in: prestera_pci(+) prestera uio_pdrv_genirq [ 28.372005] CPU: 0 PID: 1291 Comm: kworker/0:1H Not tainted 5.11.0-rc4 #1 [ 28.378846] Hardware name: DNI AmazonGo1 A7040 board (DT) [ 28.384283] Workqueue: prestera_fw_wq prestera_fw_evt_work_fn [prestera_pci] [ 28.391413] pstate: 60000085 (nZCv daIf -PAN -UAO -TCO BTYPE=--) [ 28.397468] pc : get_work_pool+0x48/0x60 [ 28.401442] lr : try_to_grab_pending+0x6c/0x1b0 [ 28.406018] sp : ffff80001391bc60 [ 28.409358] x29: ffff80001391bc60 x28: 0000000000000000 [ 28.414725] x27: ffff000104fc8b40 x26: ffff80001127de88 [ 28.420089] x25: 0000000000000000 x24: ffff000106119760 [ 28.425452] x23: ffff00010775dd60 x22: ffff00010567e000 [ 28.430814] x21: 0000000000000000 x20: ffff80001391bcb0 [ 28.436175] x19: ffff00010775deb8 x18: 00000000000000c0 [ 28.441537] x17: 0000000000000000 x16: 000000008d9b0e88 [ 28.446898] x15: 0000000000000001 x14: 00000000000002ba [ 28.452261] x13: 80a3002c00000002 x12: 00000000000005f4 [ 28.457622] x11: 0000000000000030 x10: 000000000000000c [ 28.462985] x9 : 000000000000000c x8 : 0000000000000030 [ 28.468346] x7 : ffff800014400000 x6 : ffff000106119758 [ 28.473708] x5 : 0000000000000003 x4 : ffff00010775dc60 [ 28.479068] x3 : 0000000000000000 x2 : 0000000000000060 [ 28.484429] x1 : 000071775f776600 x0 : ffff00010775deb8 [ 28.489791] Call trace: [ 28.492259] get_work_pool+0x48/0x60 [ 28.495874] cancel_delayed_work+0x38/0xb0 [ 28.500011] prestera_port_handle_event+0x90/0xa0 [prestera] [ 28.505743] prestera_evt_recv+0x98/0xe0 [prestera] [ 28.510683] prestera_fw_evt_work_fn+0x180/0x228 [prestera_pci] [ 28.516660] process_one_work+0x1e8/0x360 [ 28.520710] worker_thread+0x44/0x480 [ 28.524412] kthread+0x154/0x160 [ 28.527670] ret_from_fork+0x10/0x38 [ 28.531290] Code: a8c17bfd d50323bf d65f03c0 9278dc21 (f9400020) [ 28.537429] ---[ end trace 5eced933df3a080b ]---Show less

In the Linux kernel, the following vulnerability has been resolved: mt76: mt7921: fix possible invalid register access Disable the interrupt and synchronze for the pending irq handlers to ensure the irq tasklet is not being scheduled after the suspend to avoid the possible invalid register access acts when the host pcie controller is suspended. [17932.910534] mt7921e 0000:01:00.0: pci_pm_suspend+0x0/0x22c returned 0 after 21375 usecs [17932.910590] pcieport 0000:00:00.0: calling pci_pm_suspend+0x0/0x22c @ 18565, parent: pci0000:00 [17932.910602] pcieport 0000:00:00.0: pci_pm_suspend+0x0/0x22c returned 0 after 8 usecs [17932.910671] mtk-pcie 11230000.pcie: calling platform_pm_suspend+0x0/0x60 @ 22783, parent: soc [17932.910674] mtk-pcie 11230000.pcie: platform_pm_suspend+0x0/0x60 returned 0 after 0 usecs ... 17933.615352] x1 : 00000000000d4200 x0 : ffffff8269ca2300 [17933.620666] Call trace: [17933.623127] mt76_mmio_rr+0x28/0xf0 [mt76] [17933.627234] mt7921_rr+0x38/0x44 [mt7921e] [17933.631339] mt7921_irq_tasklet+0x54/0x1d8 [mt7921e] [17933.636309] tasklet_action_common+0x12c/0x16c [17933.640754] tasklet_action+0x24/0x2c [17933.644418] __do_softirq+0x16c/0x344 [17933.648082] irq_exit+0xa8/0xac [17933.651224] scheduler_ipi+0xd4/0x148 [17933.654890] handle_IPI+0x164/0x2d4 [17933.658379] gic_handle_irq+0x140/0x178 [17933.662216] el1_irq+0xb8/0x180 [17933.665361] cpuidle_enter_state+0xf8/0x204 [17933.669544] cpuidle_enter+0x38/0x4c [17933.673122] do_idle+0x1a4/0x2a8 [17933.676352] cpu_startup_entry+0x24/0x28 [17933.680276] rest_init+0xd4/0xe0 [17933.683508] arch_call_rest_init+0x10/0x18 [17933.687606] start_kernel+0x340/0x3b4 [17933.691279] Code: aa0003f5 d503201f f953eaa8 8b344108 (b9400113) [17933.697373] ---[ end trace a24b8e26ffbda3c5 ]--- [17933.767846] Kernel panic - not syncing: Fatal exception in interruptShow less

In the Linux kernel, the following vulnerability has been resolved: powerpc/64: Fix the definition of the fixmap area At the time being, the fixmap area is defined at the top of the address space or just below KASAN. This definition is not valid for PPC64. For PPC64, use the top of the I/O space. Because of circular dependencies, it is not possible to include asm/fixmap.h in asm/book3s/64/pgtable.h , so define a fixed size AREA at the top of the I/O space for fixmap and ensure during build that the size is big enough.Show less

In the Linux kernel, the following vulnerability has been resolved: ath10k: Fix a use after free in ath10k_htc_send_bundle In ath10k_htc_send_bundle, the bundle_skb could be freed by dev_kfree_skb_any(bundle_skb). But the bundle_skb is used later by bundle_skb->len. As skb_len = bundle_skb->len, my patch replaces bundle_skb->len to skb_len after the bundle_skb was freed.Show less

In the Linux kernel, the following vulnerability has been resolved: bnxt_en: Fix RX consumer index logic in the error path. In bnxt_rx_pkt(), the RX buffers are expected to complete in order. If the RX consumer index indicates an out of order buffer completion, it means we are hitting a hardware bug and the driver will abort all remaining RX packets and reset the RX ring. The RX consumer index that we pass to bnxt_discard_rx() is not correct. We should be passing the current index (tmp_raw_cons) instead of the old index (raw_cons). This bug can cause us to be at the wrong index when trying to abort the next RX packet. It can crash like this: #0 [ffff9bbcdf5c39a8] machine_kexec at ffffffff9b05e007 #1 [ffff9bbcdf5c3a00] __crash_kexec at ffffffff9b111232 #2 [ffff9bbcdf5c3ad0] panic at ffffffff9b07d61e #3 [ffff9bbcdf5c3b50] oops_end at ffffffff9b030978 #4 [ffff9bbcdf5c3b78] no_context at ffffffff9b06aaf0 #5 [ffff9bbcdf5c3bd8] __bad_area_nosemaphore at ffffffff9b06ae2e #6 [ffff9bbcdf5c3c28] bad_area_nosemaphore at ffffffff9b06af24 #7 [ffff9bbcdf5c3c38] __do_page_fault at ffffffff9b06b67e #8 [ffff9bbcdf5c3cb0] do_page_fault at ffffffff9b06bb12 #9 [ffff9bbcdf5c3ce0] page_fault at ffffffff9bc015c5 [exception RIP: bnxt_rx_pkt+237] RIP: ffffffffc0259cdd RSP: ffff9bbcdf5c3d98 RFLAGS: 00010213 RAX: 000000005dd8097f RBX: ffff9ba4cb11b7e0 RCX: ffffa923cf6e9000 RDX: 0000000000000fff RSI: 0000000000000627 RDI: 0000000000001000 RBP: ffff9bbcdf5c3e60 R8: 0000000000420003 R9: 000000000000020d R10: ffffa923cf6ec138 R11: ffff9bbcdf5c3e83 R12: ffff9ba4d6f928c0 R13: ffff9ba4cac28080 R14: ffff9ba4cb11b7f0 R15: ffff9ba4d5a30000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018Show less

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: fix wild memory access when clearing fragments while testing re-assembly/re-fragmentation using act_ct, it's possible to observe a crash like the following one: KASAN: maybe wild-memory-access in range [0x0001000000000448-0x000100000000044f] CPU: 50 PID: 0 Comm: swapper/50 Tainted: G S 5.12.0-rc7+ #424 Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017 RIP: 0010:inet_frag_rbtree_purge+0x50/0xc0 Code: 00 fc ff df 48 89 c3 31 ed 48 89 df e8 a9 7a 38 ff 4c 89 fe 48 89 df 49 89 c6 e8 5b 3a 38 ff 48 8d 7b 40 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 75 59 48 8d bb d0 00 00 00 4c 8b 6b 40 48 89 f8 48 RSP: 0018:ffff888c31449db8 EFLAGS: 00010203 RAX: 0000200000000089 RBX: 000100000000040e RCX: ffffffff989eb960 RDX: 0000000000000140 RSI: ffffffff97cfb977 RDI: 000100000000044e RBP: 0000000000000900 R08: 0000000000000000 R09: ffffed1186289350 R10: 0000000000000003 R11: ffffed1186289350 R12: dffffc0000000000 R13: 000100000000040e R14: 0000000000000000 R15: ffff888155e02160 FS: 0000000000000000(0000) GS:ffff888c31440000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005600cb70a5b8 CR3: 0000000a2c014005 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> inet_frag_destroy+0xa9/0x150 call_timer_fn+0x2d/0x180 run_timer_softirq+0x4fe/0xe70 __do_softirq+0x197/0x5a0 irq_exit_rcu+0x1de/0x200 sysvec_apic_timer_interrupt+0x6b/0x80 </IRQ> when act_ct temporarily stores an IP fragment, restoring the skb qdisc cb results in putting random data in FRAG_CB(), and this causes those "wild" memory accesses later, when the rbtree is purged. Never overwrite the skb cb in case tcf_ct_handle_fragments() returns -EINPROGRESS.Show less

In the Linux kernel, the following vulnerability has been resolved: net:emac/emac-mac: Fix a use after free in emac_mac_tx_buf_send In emac_mac_tx_buf_send, it calls emac_tx_fill_tpd(..,skb,..). If some error happens in emac_tx_fill_tpd(), the skb will be freed via dev_kfree_skb(skb) in error branch of emac_tx_fill_tpd(). But the freed skb is still used via skb->len by netdev_sent_queue(,skb->len). As i observed that emac_tx_fill_tpd() haven't modified the value of skb->len, thus my patch assigns skb->len to 'len' before the possible free and use 'len' instead of skb->len later.Show less

In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: Fix a use after free in siw_alloc_mr Our code analyzer reported a UAF. In siw_alloc_mr(), it calls siw_mr_add_mem(mr,..). In the implementation of siw_mr_add_mem(), mem is assigned to mr->mem and then mem is freed via kfree(mem) if xa_alloc_cyclic() failed. Here, mr->mem still point to a freed object. After, the execution continue up to the err_out branch of siw_alloc_mr, and the freed mr->mem is used in siw_mr_drop_mem(mr). My patch moves "mr->mem = mem" behind the if (xa_alloc_cyclic(..)<0) {} section, to avoid the uaf.Show less

In the Linux kernel, the following vulnerability has been resolved: mm: memcontrol: slab: fix obtain a reference to a freeing memcg Patch series "Use obj_cgroup APIs to charge kmem pages", v5. Since Roman's series "The new cgroup slab memory controller" applied. All slab objects are charged with the new APIs of obj_cgroup. The new APIs introduce a struct obj_cgroup to charge slab objects. It prevents long-living objects from pinning the original memory cgroup in the memory. But there are still some corner objects (e.g. allocations larger than order-1 page on SLUB) which are not charged with the new APIs. Those objects (include the pages which are allocated from buddy allocator directly) are charged as kmem pages which still hold a reference to the memory cgroup. E.g. We know that the kernel stack is charged as kmem pages because the size of the kernel stack can be greater than 2 pages (e.g. 16KB on x86_64 or arm64). If we create a thread (suppose the thread stack is charged to memory cgroup A) and then move it from memory cgroup A to memory cgroup B. Because the kernel stack of the thread hold a reference to the memory cgroup A. The thread can pin the memory cgroup A in the memory even if we remove the cgroup A. If we want to see this scenario by using the following script. We can see that the system has added 500 dying cgroups (This is not a real world issue, just a script to show that the large kmallocs are charged as kmem pages which can pin the memory cgroup in the memory). #!/bin/bash cat /proc/cgroups | grep memory cd /sys/fs/cgroup/memory echo 1 > memory.move_charge_at_immigrate for i in range{1..500} do mkdir kmem_test echo $$ > kmem_test/cgroup.procs sleep 3600 & echo $$ > cgroup.procs echo `cat kmem_test/cgroup.procs` > cgroup.procs rmdir kmem_test done cat /proc/cgroups | grep memory This patchset aims to make those kmem pages to drop the reference to memory cgroup by using the APIs of obj_cgroup. Finally, we can see that the number of the dying cgroups will not increase if we run the above test script. This patch (of 7): The rcu_read_lock/unlock only can guarantee that the memcg will not be freed, but it cannot guarantee the success of css_get (which is in the refill_stock when cached memcg changed) to memcg. rcu_read_lock() memcg = obj_cgroup_memcg(old) __memcg_kmem_uncharge(memcg) refill_stock(memcg) if (stock->cached != memcg) // css_get can change the ref counter from 0 back to 1. css_get(&memcg->css) rcu_read_unlock() This fix is very like the commit: eefbfa7fd678 ("mm: memcg/slab: fix use after free in obj_cgroup_charge") Fix this by holding a reference to the memcg which is passed to the __memcg_kmem_uncharge() before calling __memcg_kmem_uncharge().Show less

In the Linux kernel, the following vulnerability has been resolved: net: Only allow init netns to set default tcp cong to a restricted algo tcp_set_default_congestion_control() is netns-safe in that it writes to &net->ipv4.tcp_congestion_control, but it also sets ca->flags |= TCP_CONG_NON_RESTRICTED which is not namespaced. This has the unintended side-effect of changing the global net.ipv4.tcp_allowed_congestion_control sysctl, despite the fact that it is read-only: 97684f0970f6 ("net: Make tcp_allowed_congestion_control readonly in non-init netns") Resolve this netns "leak" by only allowing the init netns to set the default algorithm to one that is restricted. This restriction could be removed if tcp_allowed_congestion_control were namespace-ified in the future. This bug was uncovered with https://github.com/JonathonReinhart/linux-netns-sysctl-verifyShow less

In the Linux kernel, the following vulnerability has been resolved: KEYS: trusted: Fix memory leak on object td Two error return paths are neglecting to free allocated object td, causing a memory leak. Fix this by returning via the error return path that securely kfree's td. Fixes clang scan-build warning: security/keys/trusted-keys/trusted_tpm1.c:496:10: warning: Potential memory leak [unix.Malloc]Show less

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Make sure GHCB is mapped before updating Access to the GHCB is mainly in the VMGEXIT path and it is known that the GHCB will be mapped. But there are two paths where it is possible the GHCB might not be mapped. The sev_vcpu_deliver_sipi_vector() routine will update the GHCB to inform the caller of the AP Reset Hold NAE event that a SIPI has been delivered. However, if a SIPI is performed without a corresponding AP Reset Hold, then the GHCB might not be mapped (depending on the previous VMEXIT), which will result in a NULL pointer dereference. The svm_complete_emulated_msr() routine will update the GHCB to inform the caller of a RDMSR/WRMSR operation about any errors. While it is likely that the GHCB will be mapped in this situation, add a safe guard in this path to be certain a NULL pointer dereference is not encountered.Show less

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix panic during f2fs_resize_fs() f2fs_resize_fs() hangs in below callstack with testcase: - mkfs 16GB image & mount image - dd 8GB fileA - dd 8GB fileB - sync - rm fileA - sync - resize filesystem to 8GB kernel BUG at segment.c:2484! Call Trace: allocate_segment_by_default+0x92/0xf0 [f2fs] f2fs_allocate_data_block+0x44b/0x7e0 [f2fs] do_write_page+0x5a/0x110 [f2fs] f2fs_outplace_write_data+0x55/0x100 [f2fs] f2fs_do_write_data_page+0x392/0x850 [f2fs] move_data_page+0x233/0x320 [f2fs] do_garbage_collect+0x14d9/0x1660 [f2fs] free_segment_range+0x1f7/0x310 [f2fs] f2fs_resize_fs+0x118/0x330 [f2fs] __f2fs_ioctl+0x487/0x3680 [f2fs] __x64_sys_ioctl+0x8e/0xd0 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The root cause is we forgot to check that whether we have enough space in resized filesystem to store all valid blocks in before-resizing filesystem, then allocator will run out-of-space during block migration in free_segment_range().Show less

In the Linux kernel, the following vulnerability has been resolved: ARM: 9064/1: hw_breakpoint: Do not directly check the event's overflow_handler hook The commit 1879445dfa7b ("perf/core: Set event's default ::overflow_handler()") set a default event->overflow_handler in perf_event_alloc(), and replace the check event->overflow_handler with is_default_overflow_handler(), but one is missing. Currently, the bp->overflow_handler can not be NULL. As a result, enable_single_step() is always not invoked. Comments from Zhen Lei: https://patchwork.kernel.org/project/linux-arm-kernel/patch/20210207105934.2001-1-thunder.leizhen@huawei.com/Show less

In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: Fix NULL pointer dereference for ->get_features() get_features ops of pci_epc_ops may return NULL, causing NULL pointer dereference in pci_epf_test_alloc_space function. Let us add a check for pci_epc_feature pointer in pci_epf_test_bind before we access it to avoid any such NULL pointer dereference and return -ENOTSUPP in case pci_epc_feature is not found. When the patch is not applied and EPC features is not implemented in the platform driver, we see the following dump due to kernel NULL pointer dereference. Call trace: pci_epf_test_bind+0xf4/0x388 pci_epf_bind+0x3c/0x80 pci_epc_epf_link+0xa8/0xcc configfs_symlink+0x1a4/0x48c vfs_symlink+0x104/0x184 do_symlinkat+0x80/0xd4 __arm64_sys_symlinkat+0x1c/0x24 el0_svc_common.constprop.3+0xb8/0x170 el0_svc_handler+0x70/0x88 el0_svc+0x8/0x640 Code: d2800581 b9403ab9 f9404ebb 8b394f60 (f9400400) ---[ end trace a438e3c5a24f9df0 ]---Show less

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid touching checkpointed data in get_victim() In CP disabling mode, there are two issues when using LFS or SSR | AT_SSR mode to select victim: 1. LFS is set to find source section during GC, the victim should have no checkpointed data, since after GC, section could not be set free for reuse. Previously, we only check valid chpt blocks in current segment rather than section, fix it. 2. SSR | AT_SSR are set to find target segment for writes which can be fully filled by checkpointed and newly written blocks, we should never select such segment, otherwise it can cause panic or data corruption during allocation, potential case is described as below: a) target segment has 'n' (n < 512) ckpt valid blocks b) GC migrates 'n' valid blocks to other segment (segment is still in dirty list) c) GC migrates '512 - n' blocks to target segment (segment has 'n' cp_vblocks and '512 - n' vblocks) d) If GC selects target segment via {AT,}SSR allocator, however there is no free space in targe segment.Show less

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: Fix potential null dereference on pointer status There are calls to idxd_cmd_exec that pass a null status pointer however a recent commit has added an assignment to *status that can end up with a null pointer dereference. The function expects a null status pointer sometimes as there is a later assignment to *status where status is first null checked. Fix the issue by null checking status before making the assignment. Addresses-Coverity: ("Explicit null dereferenced")Show less