Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix re-dirty process of tree-log nodes There is a report of a transaction abort of -EAGAIN with the following script. #!/bin/sh for d in sda sdb; do mkfs.btrfs -d single -m single -f /dev/\${d} done mount /dev/sda /mnt/test mount /dev/sdb /mnt/scratch for dir in test scratch; do echo 3 >/proc/sys/vm/drop_caches fio --directory=/mnt/\${dir} --name=fio.\${dir} --rw=read --size=50G --bs=64m \ --numjobs=$(nproc) --time_based --ramp_time=5 --runtime=480 \ --group_reporting |& tee /dev/shm/fio.\${dir} echo 3 >/proc/sys/vm/drop_caches done for d in sda sdb; do umount /dev/\${d} done The stack trace is shown in below. [3310.967991] BTRFS: error (device sda) in btrfs_commit_transaction:2341: errno=-11 unknown (Error while writing out transaction) [3310.968060] BTRFS info (device sda): forced readonly [3310.968064] BTRFS warning (device sda): Skipping commit of aborted transaction. [3310.968065] ------------[ cut here ]------------ [3310.968066] BTRFS: Transaction aborted (error -11) [3310.968074] WARNING: CPU: 14 PID: 1684 at fs/btrfs/transaction.c:1946 btrfs_commit_transaction.cold+0x209/0x2c8 [3310.968131] CPU: 14 PID: 1684 Comm: fio Not tainted 5.14.10-300.fc35.x86_64 #1 [3310.968135] Hardware name: DIAWAY Tartu/Tartu, BIOS V2.01.B10 04/08/2021 [3310.968137] RIP: 0010:btrfs_commit_transaction.cold+0x209/0x2c8 [3310.968144] RSP: 0018:ffffb284ce393e10 EFLAGS: 00010282 [3310.968147] RAX: 0000000000000026 RBX: ffff973f147b0f60 RCX: 0000000000000027 [3310.968149] RDX: ffff974ecf098a08 RSI: 0000000000000001 RDI: ffff974ecf098a00 [3310.968150] RBP: ffff973f147b0f08 R08: 0000000000000000 R09: ffffb284ce393c48 [3310.968151] R10: ffffb284ce393c40 R11: ffffffff84f47468 R12: ffff973f101bfc00 [3310.968153] R13: ffff971f20cf2000 R14: 00000000fffffff5 R15: ffff973f147b0e58 [3310.968154] FS: 00007efe65468740(0000) GS:ffff974ecf080000(0000) knlGS:0000000000000000 [3310.968157] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [3310.968158] CR2: 000055691bcbe260 CR3: 000000105cfa4001 CR4: 0000000000770ee0 [3310.968160] PKRU: 55555554 [3310.968161] Call Trace: [3310.968167] ? dput+0xd4/0x300 [3310.968174] btrfs_sync_file+0x3f1/0x490 [3310.968180] __x64_sys_fsync+0x33/0x60 [3310.968185] do_syscall_64+0x3b/0x90 [3310.968190] entry_SYSCALL_64_after_hwframe+0x44/0xae [3310.968194] RIP: 0033:0x7efe6557329b [3310.968200] RSP: 002b:00007ffe0236ebc0 EFLAGS: 00000293 ORIG_RAX: 000000000000004a [3310.968203] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007efe6557329b [3310.968204] RDX: 0000000000000000 RSI: 00007efe58d77010 RDI: 0000000000000006 [3310.968205] RBP: 0000000004000000 R08: 0000000000000000 R09: 00007efe58d77010 [3310.968207] R10: 0000000016cacc0c R11: 0000000000000293 R12: 00007efe5ce95980 [3310.968208] R13: 0000000000000000 R14: 00007efe6447c790 R15: 0000000c80000000 [3310.968212] ---[ end trace 1a346f4d3c0d96ba ]--- [3310.968214] BTRFS: error (device sda) in cleanup_transaction:1946: errno=-11 unknown The abort occurs because of a write hole while writing out freeing tree nodes of a tree-log tree. For zoned btrfs, we re-dirty a freed tree node to ensure btrfs can write the region and does not leave a hole on write on a zoned device. The current code fails to re-dirty a node when the tree-log tree's depth is greater or equal to 2. That leads to a transaction abort with -EAGAIN. Fix the issue by properly re-dirtying a node on walking up the tree.Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: oss: Limit the period size to 16MB Set the practical limit to the period size (the fragment shift in OSS) instead of a full 31bit; a too large value could lead to the exhaust of memory as we allocate temporary buffers of the period size, too. As of this patch, we set to 16MB limit, which should cover all use cases.Show less

In the Linux kernel, the following vulnerability has been resolved: btrfs: free exchange changeset on failures Fstests runs on my VMs have show several kmemleak reports like the following. unreferenced object 0xffff88811ae59080 (size 64): comm "xfs_io", pid 12124, jiffies 4294987392 (age 6.368s) hex dump (first 32 bytes): 00 c0 1c 00 00 00 00 00 ff cf 1c 00 00 00 00 00 ................ 90 97 e5 1a 81 88 ff ff 90 97 e5 1a 81 88 ff ff ................ backtrace: [<00000000ac0176d2>] ulist_add_merge+0x60/0x150 [btrfs] [<0000000076e9f312>] set_state_bits+0x86/0xc0 [btrfs] [<0000000014fe73d6>] set_extent_bit+0x270/0x690 [btrfs] [<000000004f675208>] set_record_extent_bits+0x19/0x20 [btrfs] [<00000000b96137b1>] qgroup_reserve_data+0x274/0x310 [btrfs] [<0000000057e9dcbb>] btrfs_check_data_free_space+0x5c/0xa0 [btrfs] [<0000000019c4511d>] btrfs_delalloc_reserve_space+0x1b/0xa0 [btrfs] [<000000006d37e007>] btrfs_dio_iomap_begin+0x415/0x970 [btrfs] [<00000000fb8a74b8>] iomap_iter+0x161/0x1e0 [<0000000071dff6ff>] __iomap_dio_rw+0x1df/0x700 [<000000002567ba53>] iomap_dio_rw+0x5/0x20 [<0000000072e555f8>] btrfs_file_write_iter+0x290/0x530 [btrfs] [<000000005eb3d845>] new_sync_write+0x106/0x180 [<000000003fb505bf>] vfs_write+0x24d/0x2f0 [<000000009bb57d37>] __x64_sys_pwrite64+0x69/0xa0 [<000000003eba3fdf>] do_syscall_64+0x43/0x90 In case brtfs_qgroup_reserve_data() or btrfs_delalloc_reserve_metadata() fail the allocated extent_changeset will not be freed. So in btrfs_check_data_free_space() and btrfs_delalloc_reserve_space() free the allocated extent_changeset to get rid of the allocated memory. The issue currently only happens in the direct IO write path, but only after 65b3c08606e5 ("btrfs: fix ENOSPC failure when attempting direct IO write into NOCOW range"), and also at defrag_one_locked_target(). Every other place is always calling extent_changeset_free() even if its call to btrfs_delalloc_reserve_space() or btrfs_check_data_free_space() has failed.Show less

In the Linux kernel, the following vulnerability has been resolved: nfsd: Fix nsfd startup race (again) Commit bd5ae9288d64 ("nfsd: register pernet ops last, unregister first") has re-opened rpc_pipefs_event() race against nfsd_net_id registration (register_pernet_subsys()) which has been fixed by commit bb7ffbf29e76 ("nfsd: fix nsfd startup race triggering BUG_ON"). Restore the order of register_pernet_subsys() vs register_cld_notifier(). Add WARN_ON() to prevent a future regression. Crash info: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000012 CPU: 8 PID: 345 Comm: mount Not tainted 5.4.144-... #1 pc : rpc_pipefs_event+0x54/0x120 [nfsd] lr : rpc_pipefs_event+0x48/0x120 [nfsd] Call trace: rpc_pipefs_event+0x54/0x120 [nfsd] blocking_notifier_call_chain rpc_fill_super get_tree_keyed rpc_fs_get_tree vfs_get_tree do_mount ksys_mount __arm64_sys_mount el0_svc_handler el0_svcShow less

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.Show less

In the Linux kernel, the following vulnerability has been resolved: aio: fix use-after-free due to missing POLLFREE handling signalfd_poll() and binder_poll() are special in that they use a waitqueue whose lifetime is the current task, rather than the struct file as is normally the case. This is okay for blocking polls, since a blocking poll occurs within one task; however, non-blocking polls require another solution. This solution is for the queue to be cleared before it is freed, by sending a POLLFREE notification to all waiters. Unfortunately, only eventpoll handles POLLFREE. A second type of non-blocking poll, aio poll, was added in kernel v4.18, and it doesn't handle POLLFREE. This allows a use-after-free to occur if a signalfd or binder fd is polled with aio poll, and the waitqueue gets freed. Fix this by making aio poll handle POLLFREE. A patch by Ramji Jiyani <ramjiyani@google.com> (https://lore.kernel.org/r/20211027011834.2497484-1-ramjiyani@google.com) tried to do this by making aio_poll_wake() always complete the request inline if POLLFREE is seen. However, that solution had two bugs. First, it introduced a deadlock, as it unconditionally locked the aio context while holding the waitqueue lock, which inverts the normal locking order. Second, it didn't consider that POLLFREE notifications are missed while the request has been temporarily de-queued. The second problem was solved by my previous patch. This patch then properly fixes the use-after-free by handling POLLFREE in a deadlock-free way. It does this by taking advantage of the fact that freeing of the waitqueue is RCU-delayed, similar to what eventpoll does.Show less

In the Linux kernel, the following vulnerability has been resolved: io_uring: ensure task_work gets run as part of cancelations If we successfully cancel a work item but that work item needs to be processed through task_work, then we can be sleeping uninterruptibly in io_uring_cancel_generic() and never process it. Hence we don't make forward progress and we end up with an uninterruptible sleep warning. While in there, correct a comment that should be IFF, not IIF.Show less

In the Linux kernel, the following vulnerability has been resolved: scsi: pm80xx: Do not call scsi_remove_host() in pm8001_alloc() Calling scsi_remove_host() before scsi_add_host() results in a crash: BUG: kernel NULL pointer dereference, address: 0000000000000108 RIP: 0010:device_del+0x63/0x440 Call Trace: device_unregister+0x17/0x60 scsi_remove_host+0xee/0x2a0 pm8001_pci_probe+0x6ef/0x1b90 [pm80xx] local_pci_probe+0x3f/0x90 We cannot call scsi_remove_host() in pm8001_alloc() because scsi_add_host() has not been called yet at that point in time. Function call tree: pm8001_pci_probe() | `- pm8001_pci_alloc() | | | `- pm8001_alloc() | | | `- scsi_remove_host() | `- scsi_add_host()Show less

In the Linux kernel, the following vulnerability has been resolved: ASoC: codecs: wcd934x: handle channel mappping list correctly Currently each channel is added as list to dai channel list, however there is danger of adding same channel to multiple dai channel list which endups corrupting the other list where its already added. This patch ensures that the channel is actually free before adding to the dai channel list and also ensures that the channel is on the list before deleting it. This check was missing previously, and we did not hit this issue as we were testing very simple usecases with sequence of amixer commands.Show less

In the Linux kernel, the following vulnerability has been resolved: i40e: Fix NULL pointer dereference in i40e_dbg_dump_desc When trying to dump VFs VSI RX/TX descriptors using debugfs there was a crash due to NULL pointer dereference in i40e_dbg_dump_desc. Added a check to i40e_dbg_dump_desc that checks if VSI type is correct for dumping RX/TX descriptors.Show less

In the Linux kernel, the following vulnerability has been resolved: iio: mma8452: Fix trigger reference couting The mma8452 driver directly assigns a trigger to the struct iio_dev. The IIO core when done using this trigger will call `iio_trigger_put()` to drop the reference count by 1. Without the matching `iio_trigger_get()` in the driver the reference count can reach 0 too early, the trigger gets freed while still in use and a use-after-free occurs. Fix this by getting a reference to the trigger before assigning it to the IIO device.Show less

In the Linux kernel, the following vulnerability has been resolved: iio: accel: kxcjk-1013: Fix possible memory leak in probe and remove When ACPI type is ACPI_SMO8500, the data->dready_trig will not be set, the memory allocated by iio_triggered_buffer_setup() will not be freed, and cause memory leak as follows: unreferenced object 0xffff888009551400 (size 512): comm "i2c-SMO8500-125", pid 911, jiffies 4294911787 (age 83.852s) hex dump (first 32 bytes): 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 20 e2 e5 c0 ff ff ff ff ........ ....... backtrace: [<0000000041ce75ee>] kmem_cache_alloc_trace+0x16d/0x360 [<000000000aeb17b0>] iio_kfifo_allocate+0x41/0x130 [kfifo_buf] [<000000004b40c1f5>] iio_triggered_buffer_setup_ext+0x2c/0x210 [industrialio_triggered_buffer] [<000000004375b15f>] kxcjk1013_probe+0x10c3/0x1d81 [kxcjk_1013] Fix it by remove data->dready_trig condition in probe and remove.Show less

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix slab-use-after-free in l2cap_connect() Extend a critical section to prevent chan from early freeing. Also make the l2cap_connect() return type void. Nothing is using the returned value but it is ugly to return a potentially freed pointer. Making it void will help with backports because earlier kernels did use the return value. Now the compile will break for kernels where this patch is not a complete fix. Call stack summary: [use] l2cap_bredr_sig_cmd l2cap_connect ┌ mutex_lock(&conn->chan_lock); │ chan = pchan->ops->new_connection(pchan); <- alloc chan │ __l2cap_chan_add(conn, chan); │ l2cap_chan_hold(chan); │ list_add(&chan->list, &conn->chan_l); ... (1) └ mutex_unlock(&conn->chan_lock); chan->conf_state ... (4) <- use after free [free] l2cap_conn_del ┌ mutex_lock(&conn->chan_lock); │ foreach chan in conn->chan_l: ... (2) │ l2cap_chan_put(chan); │ l2cap_chan_destroy │ kfree(chan) ... (3) <- chan freed └ mutex_unlock(&conn->chan_lock); ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: slab-use-after-free in l2cap_connect+0xa67/0x11a0 net/bluetooth/l2cap_core.c:4260 Read of size 8 at addr ffff88810bf040a0 by task kworker/u3:1/311Show less

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: msft: fix slab-use-after-free in msft_do_close() Tying the msft->data lifetime to hdev by freeing it in hci_release_dev() to fix the following case: [use] msft_do_close() msft = hdev->msft_data; if (!msft) ...(1) <- passed. return; mutex_lock(&msft->filter_lock); ...(4) <- used after freed. [free] msft_unregister() msft = hdev->msft_data; hdev->msft_data = NULL; ...(2) kfree(msft); ...(3) <- msft is freed. ================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:587 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x8f/0xc30 kernel/locking/mutex.c:752 Read of size 8 at addr ffff888106cbbca8 by task kworker/u5:2/309Show less

In the Linux kernel, the following vulnerability has been resolved: igb: Fix string truncation warnings in igb_set_fw_version Commit 1978d3ead82c ("intel: fix string truncation warnings") fixes '-Wformat-truncation=' warnings in igb_main.c by using kasprintf. drivers/net/ethernet/intel/igb/igb_main.c:3092:53: warning：‘%d’ directive output may be truncated writing between 1 and 5 bytes into a region of size between 1 and 13 [-Wformat-truncation=] 3092 | "%d.%d, 0x%08x, %d.%d.%d", | ^~ drivers/net/ethernet/intel/igb/igb_main.c:3092:34: note：directive argument in the range [0, 65535] 3092 | "%d.%d, 0x%08x, %d.%d.%d", | ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/intel/igb/igb_main.c:3092:34: note：directive argument in the range [0, 65535] drivers/net/ethernet/intel/igb/igb_main.c:3090:25: note：‘snprintf’ output between 23 and 43 bytes into a destination of size 32 kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Fix this warning by using a larger space for adapter->fw_version, and then fall back and continue to use snprintf.Show less

In the Linux kernel, the following vulnerability has been resolved: dm rq: don't queue request to blk-mq during DM suspend DM uses blk-mq's quiesce/unquiesce to stop/start device mapper queue. But blk-mq's unquiesce may come from outside events, such as elevator switch, updating nr_requests or others, and request may come during suspend, so simply ask for blk-mq to requeue it. Fixes one kernel panic issue when running updating nr_requests and dm-mpath suspend/resume stress test.Show less

In the Linux kernel, the following vulnerability has been resolved: nvmem: Fix shift-out-of-bound (UBSAN) with byte size cells If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0); will become undefined behavior because nbits modulo BITS_PER_BYTE is 0, and we subtract one from that making a large number that is then shifted more than the number of bits that fit into an unsigned long. UBSAN reports this problem: UBSAN: shift-out-of-bounds in drivers/nvmem/core.c:1386:8 shift exponent 64 is too large for 64-bit type 'unsigned long' CPU: 6 PID: 7 Comm: kworker/u16:0 Not tainted 5.15.0-rc3+ #9 Hardware name: Google Lazor (rev3+) with KB Backlight (DT) Workqueue: events_unbound deferred_probe_work_func Call trace: dump_backtrace+0x0/0x170 show_stack+0x24/0x30 dump_stack_lvl+0x64/0x7c dump_stack+0x18/0x38 ubsan_epilogue+0x10/0x54 __ubsan_handle_shift_out_of_bounds+0x180/0x194 __nvmem_cell_read+0x1ec/0x21c nvmem_cell_read+0x58/0x94 nvmem_cell_read_variable_common+0x4c/0xb0 nvmem_cell_read_variable_le_u32+0x40/0x100 a6xx_gpu_init+0x170/0x2f4 adreno_bind+0x174/0x284 component_bind_all+0xf0/0x264 msm_drm_bind+0x1d8/0x7a0 try_to_bring_up_master+0x164/0x1ac __component_add+0xbc/0x13c component_add+0x20/0x2c dp_display_probe+0x340/0x384 platform_probe+0xc0/0x100 really_probe+0x110/0x304 __driver_probe_device+0xb8/0x120 driver_probe_device+0x4c/0xfc __device_attach_driver+0xb0/0x128 bus_for_each_drv+0x90/0xdc __device_attach+0xc8/0x174 device_initial_probe+0x20/0x2c bus_probe_device+0x40/0xa4 deferred_probe_work_func+0x7c/0xb8 process_one_work+0x128/0x21c process_scheduled_works+0x40/0x54 worker_thread+0x1ec/0x2a8 kthread+0x138/0x158 ret_from_fork+0x10/0x20 Fix it by making sure there are any bits to mask out.Show less

In the Linux kernel, the following vulnerability has been resolved: net/tls: Fix flipped sign in tls_err_abort() calls sk->sk_err appears to expect a positive value, a convention that ktls doesn't always follow and that leads to memory corruption in other code. For instance, [kworker] tls_encrypt_done(..., err=<negative error from crypto request>) tls_err_abort(.., err) sk->sk_err = err; [task] splice_from_pipe_feed ... tls_sw_do_sendpage if (sk->sk_err) { ret = -sk->sk_err; // ret is positive splice_from_pipe_feed (continued) ret = actor(...) // ret is still positive and interpreted as bytes // written, resulting in underflow of buf->len and // sd->len, leading to huge buf->offset and bogus // addresses computed in later calls to actor() Fix all tls_err_abort() callers to pass a negative error code consistently and centralize the error-prone sign flip there, throwing in a warning to catch future misuse and uninlining the function so it really does only warn once.Show less

In the Linux kernel, the following vulnerability has been resolved: usbnet: sanity check for maxpacket maxpacket of 0 makes no sense and oopses as we need to divide by it. Give up. V2: fixed typo in log and stylistic issuesShow less