Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: ext4: fix bug_on in __es_tree_search Hulk Robot reported a BUG_ON: ================================================================== kernel BUG at fs/ext4/extents_status.c:199! [...] RIP: 0010:ext4_es_end fs/ext4/extents_status.c:199 [inline] RIP: 0010:__es_tree_search+0x1e0/0x260 fs/ext4/extents_status.c:217 [...] Call Trace: ext4_es_cache_extent+0x109/0x340 fs/ext4/extents_status.c:766 ext4_cache_extents+0x239/0x2e0 fs/ext4/extents.c:561 ext4_find_extent+0x6b7/0xa20 fs/ext4/extents.c:964 ext4_ext_map_blocks+0x16b/0x4b70 fs/ext4/extents.c:4384 ext4_map_blocks+0xe26/0x19f0 fs/ext4/inode.c:567 ext4_getblk+0x320/0x4c0 fs/ext4/inode.c:980 ext4_bread+0x2d/0x170 fs/ext4/inode.c:1031 ext4_quota_read+0x248/0x320 fs/ext4/super.c:6257 v2_read_header+0x78/0x110 fs/quota/quota_v2.c:63 v2_check_quota_file+0x76/0x230 fs/quota/quota_v2.c:82 vfs_load_quota_inode+0x5d1/0x1530 fs/quota/dquot.c:2368 dquot_enable+0x28a/0x330 fs/quota/dquot.c:2490 ext4_quota_enable fs/ext4/super.c:6137 [inline] ext4_enable_quotas+0x5d7/0x960 fs/ext4/super.c:6163 ext4_fill_super+0xa7c9/0xdc00 fs/ext4/super.c:4754 mount_bdev+0x2e9/0x3b0 fs/super.c:1158 mount_fs+0x4b/0x1e4 fs/super.c:1261 [...] ================================================================== Above issue may happen as follows: ------------------------------------- ext4_fill_super ext4_enable_quotas ext4_quota_enable ext4_iget __ext4_iget ext4_ext_check_inode ext4_ext_check __ext4_ext_check ext4_valid_extent_entries Check for overlapping extents does't take effect dquot_enable vfs_load_quota_inode v2_check_quota_file v2_read_header ext4_quota_read ext4_bread ext4_getblk ext4_map_blocks ext4_ext_map_blocks ext4_find_extent ext4_cache_extents ext4_es_cache_extent ext4_es_cache_extent __es_tree_search ext4_es_end BUG_ON(es->es_lblk + es->es_len < es->es_lblk) The error ext4 extents is as follows: 0af3 0300 0400 0000 00000000 extent_header 00000000 0100 0000 12000000 extent1 00000000 0100 0000 18000000 extent2 02000000 0400 0000 14000000 extent3 In the ext4_valid_extent_entries function, if prev is 0, no error is returned even if lblock<=prev. This was intended to skip the check on the first extent, but in the error image above, prev=0+1-1=0 when checking the second extent, so even though lblock<=prev, the function does not return an error. As a result, bug_ON occurs in __es_tree_search and the system panics. To solve this problem, we only need to check that: 1. The lblock of the first extent is not less than 0. 2. The lblock of the next extent is not less than the next block of the previous extent. The same applies to extent_idx.Show less

In the Linux kernel, the following vulnerability has been resolved: ext4: fix memory leak in parse_apply_sb_mount_options() If processing the on-disk mount options fails after any memory was allocated in the ext4_fs_context, e.g. s_qf_names, then this memory is leaked. Fix this by calling ext4_fc_free() instead of kfree() directly. Reproducer: mkfs.ext4 -F /dev/vdc tune2fs /dev/vdc -E mount_opts=usrjquota=file echo clear > /sys/kernel/debug/kmemleak mount /dev/vdc /vdc echo scan > /sys/kernel/debug/kmemleak sleep 5 echo scan > /sys/kernel/debug/kmemleak cat /sys/kernel/debug/kmemleakShow less

In the Linux kernel, the following vulnerability has been resolved: dlm: fix plock invalid read This patch fixes an invalid read showed by KASAN. A unlock will allocate a "struct plock_op" and a followed send_op() will append it to a global send_list data structure. In some cases a followed dev_read() moves it to recv_list and dev_write() will cast it to "struct plock_xop" and access fields which are only available in those structures. At this point an invalid read happens by accessing those fields. To fix this issue the "callback" field is moved to "struct plock_op" to indicate that a cast to "plock_xop" is allowed and does the additional "plock_xop" handling if set. Example of the KASAN output which showed the invalid read: [ 2064.296453] ================================================================== [ 2064.304852] BUG: KASAN: slab-out-of-bounds in dev_write+0x52b/0x5a0 [dlm] [ 2064.306491] Read of size 8 at addr ffff88800ef227d8 by task dlm_controld/7484 [ 2064.308168] [ 2064.308575] CPU: 0 PID: 7484 Comm: dlm_controld Kdump: loaded Not tainted 5.14.0+ #9 [ 2064.310292] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 2064.311618] Call Trace: [ 2064.312218] dump_stack_lvl+0x56/0x7b [ 2064.313150] print_address_description.constprop.8+0x21/0x150 [ 2064.314578] ? dev_write+0x52b/0x5a0 [dlm] [ 2064.315610] ? dev_write+0x52b/0x5a0 [dlm] [ 2064.316595] kasan_report.cold.14+0x7f/0x11b [ 2064.317674] ? dev_write+0x52b/0x5a0 [dlm] [ 2064.318687] dev_write+0x52b/0x5a0 [dlm] [ 2064.319629] ? dev_read+0x4a0/0x4a0 [dlm] [ 2064.320713] ? bpf_lsm_kernfs_init_security+0x10/0x10 [ 2064.321926] vfs_write+0x17e/0x930 [ 2064.322769] ? __fget_light+0x1aa/0x220 [ 2064.323753] ksys_write+0xf1/0x1c0 [ 2064.324548] ? __ia32_sys_read+0xb0/0xb0 [ 2064.325464] do_syscall_64+0x3a/0x80 [ 2064.326387] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 2064.327606] RIP: 0033:0x7f807e4ba96f [ 2064.328470] Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 39 87 f8 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 7c 87 f8 ff 48 [ 2064.332902] RSP: 002b:00007ffd50cfe6e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 [ 2064.334658] RAX: ffffffffffffffda RBX: 000055cc3886eb30 RCX: 00007f807e4ba96f [ 2064.336275] RDX: 0000000000000040 RSI: 00007ffd50cfe7e0 RDI: 0000000000000010 [ 2064.337980] RBP: 00007ffd50cfe7e0 R08: 0000000000000000 R09: 0000000000000001 [ 2064.339560] R10: 000055cc3886eb30 R11: 0000000000000293 R12: 000055cc3886eb80 [ 2064.341237] R13: 000055cc3886eb00 R14: 000055cc3886f590 R15: 0000000000000001 [ 2064.342857] [ 2064.343226] Allocated by task 12438: [ 2064.344057] kasan_save_stack+0x1c/0x40 [ 2064.345079] __kasan_kmalloc+0x84/0xa0 [ 2064.345933] kmem_cache_alloc_trace+0x13b/0x220 [ 2064.346953] dlm_posix_unlock+0xec/0x720 [dlm] [ 2064.348811] do_lock_file_wait.part.32+0xca/0x1d0 [ 2064.351070] fcntl_setlk+0x281/0xbc0 [ 2064.352879] do_fcntl+0x5e4/0xfe0 [ 2064.354657] __x64_sys_fcntl+0x11f/0x170 [ 2064.356550] do_syscall_64+0x3a/0x80 [ 2064.358259] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 2064.360745] [ 2064.361511] Last potentially related work creation: [ 2064.363957] kasan_save_stack+0x1c/0x40 [ 2064.365811] __kasan_record_aux_stack+0xaf/0xc0 [ 2064.368100] call_rcu+0x11b/0xf70 [ 2064.369785] dlm_process_incoming_buffer+0x47d/0xfd0 [dlm] [ 2064.372404] receive_from_sock+0x290/0x770 [dlm] [ 2064.374607] process_recv_sockets+0x32/0x40 [dlm] [ 2064.377290] process_one_work+0x9a8/0x16e0 [ 2064.379357] worker_thread+0x87/0xbf0 [ 2064.381188] kthread+0x3ac/0x490 [ 2064.383460] ret_from_fork+0x22/0x30 [ 2064.385588] [ 2064.386518] Second to last potentially related work creation: [ 2064.389219] kasan_save_stack+0x1c/0x40 [ 2064.391043] __kasan_record_aux_stack+0xaf/0xc0 [ 2064.393303] call_rcu+0x11b/0xf70 [ 2064.394885] dlm_process_incoming_buffer+0x47d/0xfd0 [dlm] [ 2064.397694] receive_from_sock+0x290/0x770 ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: block: Fix potential deadlock in blk_ia_range_sysfs_show() When being read, a sysfs attribute is already protected against removal with the kobject node active reference counter. As a result, in blk_ia_range_sysfs_show(), there is no need to take the queue sysfs lock when reading the value of a range attribute. Using the queue sysfs lock in this function creates a potential deadlock situation with the disk removal, something that a lockdep signals with a splat when the device is removed: [ 760.703551] Possible unsafe locking scenario: [ 760.703551] [ 760.703554] CPU0 CPU1 [ 760.703556] ---- ---- [ 760.703558] lock(&q->sysfs_lock); [ 760.703565] lock(kn->active#385); [ 760.703573] lock(&q->sysfs_lock); [ 760.703579] lock(kn->active#385); [ 760.703587] [ 760.703587] *** DEADLOCK *** Solve this by removing the mutex_lock()/mutex_unlock() calls from blk_ia_range_sysfs_show().Show less

In the Linux kernel, the following vulnerability has been resolved: staging: r8188eu: prevent ->Ssid overflow in rtw_wx_set_scan() This code has a check to prevent read overflow but it needs another check to prevent writing beyond the end of the ->Ssid[] array.Show less

In the Linux kernel, the following vulnerability has been resolved: RDMA/hfi1: Fix potential integer multiplication overflow errors When multiplying of different types, an overflow is possible even when storing the result in a larger type. This is because the conversion is done after the multiplication. So arithmetic overflow and thus in incorrect value is possible. Correct an instance of this in the inter packet delay calculation. Fix by ensuring one of the operands is u64 which will promote the other to u64 as well ensuring no overflow.Show less

In the Linux kernel, the following vulnerability has been resolved: lib/string_helpers: fix not adding strarray to device's resource list Add allocated strarray to device's resource list. This is a must to automatically release strarray when the device disappears. Without this fix we have a memory leak in the few drivers which use devm_kasprintf_strarray().Show less

In the Linux kernel, the following vulnerability has been resolved: ftrace: Clean up hash direct_functions on register failures We see the following GPF when register_ftrace_direct fails: [ ] general protection fault, probably for non-canonical address \ 0x200000000000010: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI [...] [ ] RIP: 0010:ftrace_find_rec_direct+0x53/0x70 [ ] Code: 48 c1 e0 03 48 03 42 08 48 8b 10 31 c0 48 85 d2 74 [...] [ ] RSP: 0018:ffffc9000138bc10 EFLAGS: 00010206 [ ] RAX: 0000000000000000 RBX: ffffffff813e0df0 RCX: 000000000000003b [ ] RDX: 0200000000000000 RSI: 000000000000000c RDI: ffffffff813e0df0 [ ] RBP: ffffffffa00a3000 R08: ffffffff81180ce0 R09: 0000000000000001 [ ] R10: ffffc9000138bc18 R11: 0000000000000001 R12: ffffffff813e0df0 [ ] R13: ffffffff813e0df0 R14: ffff888171b56400 R15: 0000000000000000 [ ] FS: 00007fa9420c7780(0000) GS:ffff888ff6a00000(0000) knlGS:000000000 [ ] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ ] CR2: 000000000770d000 CR3: 0000000107d50003 CR4: 0000000000370ee0 [ ] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ ] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ ] Call Trace: [ ] <TASK> [ ] register_ftrace_direct+0x54/0x290 [ ] ? render_sigset_t+0xa0/0xa0 [ ] bpf_trampoline_update+0x3f5/0x4a0 [ ] ? 0xffffffffa00a3000 [ ] bpf_trampoline_link_prog+0xa9/0x140 [ ] bpf_tracing_prog_attach+0x1dc/0x450 [ ] bpf_raw_tracepoint_open+0x9a/0x1e0 [ ] ? find_held_lock+0x2d/0x90 [ ] ? lock_release+0x150/0x430 [ ] __sys_bpf+0xbd6/0x2700 [ ] ? lock_is_held_type+0xd8/0x130 [ ] __x64_sys_bpf+0x1c/0x20 [ ] do_syscall_64+0x3a/0x80 [ ] entry_SYSCALL_64_after_hwframe+0x44/0xae [ ] RIP: 0033:0x7fa9421defa9 [ ] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 9 f8 [...] [ ] RSP: 002b:00007ffed743bd78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 [ ] RAX: ffffffffffffffda RBX: 00000000069d2480 RCX: 00007fa9421defa9 [ ] RDX: 0000000000000078 RSI: 00007ffed743bd80 RDI: 0000000000000011 [ ] RBP: 00007ffed743be00 R08: 0000000000bb7270 R09: 0000000000000000 [ ] R10: 00000000069da210 R11: 0000000000000246 R12: 0000000000000001 [ ] R13: 00007ffed743c4b0 R14: 00000000069d2480 R15: 0000000000000001 [ ] </TASK> [ ] Modules linked in: klp_vm(OK) [ ] ---[ end trace 0000000000000000 ]--- One way to trigger this is: 1. load a livepatch that patches kernel function xxx; 2. run bpftrace -e 'kfunc:xxx {}', this will fail (expected for now); 3. repeat #2 => gpf. This is because the entry is added to direct_functions, but not removed. Fix this by remove the entry from direct_functions when register_ftrace_direct fails. Also remove the last trailing space from ftrace.c, so we don't have to worry about it anymore.Show less

In the Linux kernel, the following vulnerability has been resolved: mm/page_owner: use strscpy() instead of strlcpy() current->comm[] is not a string (no guarantee for a zero byte in it). strlcpy(s1, s2, l) is calling strlen(s2), potentially causing out-of-bound access, as reported by syzbot: detected buffer overflow in __fortify_strlen ------------[ cut here ]------------ kernel BUG at lib/string_helpers.c:980! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 4087 Comm: dhcpcd-run-hooks Not tainted 5.18.0-rc3-syzkaller-01537-g20b87e7c29df #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:fortify_panic+0x18/0x1a lib/string_helpers.c:980 Code: 8c e8 c5 ba e1 fa e9 23 0f bf fa e8 0b 5d 8c f8 eb db 55 48 89 fd e8 e0 49 40 f8 48 89 ee 48 c7 c7 80 f5 26 8a e8 99 09 f1 ff <0f> 0b e8 ca 49 40 f8 48 8b 54 24 18 4c 89 f1 48 c7 c7 00 00 27 8a RSP: 0018:ffffc900000074a8 EFLAGS: 00010286 RAX: 000000000000002c RBX: ffff88801226b728 RCX: 0000000000000000 RDX: ffff8880198e0000 RSI: ffffffff81600458 RDI: fffff52000000e87 RBP: ffffffff89da2aa0 R08: 000000000000002c R09: 0000000000000000 R10: ffffffff815fae2e R11: 0000000000000000 R12: ffff88801226b700 R13: ffff8880198e0830 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5876ad6ff8 CR3: 000000001a48c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: <IRQ> __fortify_strlen include/linux/fortify-string.h:128 [inline] strlcpy include/linux/fortify-string.h:143 [inline] __set_page_owner_handle+0x2b1/0x3e0 mm/page_owner.c:171 __set_page_owner+0x3e/0x50 mm/page_owner.c:190 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x8df/0xf20 mm/slub.c:3005 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092 slab_alloc_node mm/slub.c:3183 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x360/0x3b0 mm/slub.c:3242 dst_alloc+0x146/0x1f0 net/core/dst.c:92Show less

In the Linux kernel, the following vulnerability has been resolved: md: Don't set mddev private to NULL in raid0 pers->free In normal stop process, it does like this: do_md_stop | __md_stop (pers->free(); mddev->private=NULL) | md_free (free mddev) __md_stop sets mddev->private to NULL after pers->free. The raid device will be stopped and mddev memory is free. But in reshape, it doesn't free the mddev and mddev will still be used in new raid. In reshape, it first sets mddev->private to new_pers and then runs old_pers->free(). Now raid0 sets mddev->private to NULL in raid0_free. The new raid can't work anymore. It will panic when dereference mddev->private because of NULL pointer dereference. It can panic like this: [63010.814972] kernel BUG at drivers/md/raid10.c:928! [63010.819778] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [63010.825011] CPU: 3 PID: 44437 Comm: md0_resync Kdump: loaded Not tainted 5.14.0-86.el9.x86_64 #1 [63010.833789] Hardware name: Dell Inc. PowerEdge R6415/07YXFK, BIOS 1.15.0 09/11/2020 [63010.841440] RIP: 0010:raise_barrier+0x161/0x170 [raid10] [63010.865508] RSP: 0018:ffffc312408bbc10 EFLAGS: 00010246 [63010.870734] RAX: 0000000000000000 RBX: ffffa00bf7d39800 RCX: 0000000000000000 [63010.877866] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffa00bf7d39800 [63010.884999] RBP: 0000000000000000 R08: fffffa4945e74400 R09: 0000000000000000 [63010.892132] R10: ffffa00eed02f798 R11: 0000000000000000 R12: ffffa00bbc435200 [63010.899266] R13: ffffa00bf7d39800 R14: 0000000000000400 R15: 0000000000000003 [63010.906399] FS: 0000000000000000(0000) GS:ffffa00eed000000(0000) knlGS:0000000000000000 [63010.914485] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [63010.920229] CR2: 00007f5cfbe99828 CR3: 0000000105efe000 CR4: 00000000003506e0 [63010.927363] Call Trace: [63010.929822] ? bio_reset+0xe/0x40 [63010.933144] ? raid10_alloc_init_r10buf+0x60/0xa0 [raid10] [63010.938629] raid10_sync_request+0x756/0x1610 [raid10] [63010.943770] md_do_sync.cold+0x3e4/0x94c [63010.947698] md_thread+0xab/0x160 [63010.951024] ? md_write_inc+0x50/0x50 [63010.954688] kthread+0x149/0x170 [63010.957923] ? set_kthread_struct+0x40/0x40 [63010.962107] ret_from_fork+0x22/0x30 Removing the code that sets mddev->private to NULL in raid0 can fix problem.Show less

In the Linux kernel, the following vulnerability has been resolved: tty: goldfish: Use tty_port_destroy() to destroy port In goldfish_tty_probe(), the port initialized through tty_port_init() should be destroyed in error paths.In goldfish_tty_remove(), qtty->port also should be destroyed or else might leak resources. Fix the above by calling tty_port_destroy().Show less

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: gadget: Replace list_for_each_entry_safe() if using giveback The list_for_each_entry_safe() macro saves the current item (n) and the item after (n+1), so that n can be safely removed without corrupting the list. However, when traversing the list and removing items using gadget giveback, the DWC3 lock is briefly released, allowing other routines to execute. There is a situation where, while items are being removed from the cancelled_list using dwc3_gadget_ep_cleanup_cancelled_requests(), the pullup disable routine is running in parallel (due to UDC unbind). As the cleanup routine removes n, and the pullup disable removes n+1, once the cleanup retakes the DWC3 lock, it references a request who was already removed/handled. With list debug enabled, this leads to a panic. Ensure all instances of the macro are replaced where gadget giveback is used. Example call stack: Thread#1: __dwc3_gadget_ep_set_halt() - CLEAR HALT -> dwc3_gadget_ep_cleanup_cancelled_requests() ->list_for_each_entry_safe() ->dwc3_gadget_giveback(n) ->dwc3_gadget_del_and_unmap_request()- n deleted[cancelled_list] ->spin_unlock ->Thread#2 executes ... ->dwc3_gadget_giveback(n+1) ->Already removed! Thread#2: dwc3_gadget_pullup() ->waiting for dwc3 spin_lock ... ->Thread#1 released lock ->dwc3_stop_active_transfers() ->dwc3_remove_requests() ->fetches n+1 item from cancelled_list (n removed by Thread#1) ->dwc3_gadget_giveback() ->dwc3_gadget_del_and_unmap_request()- n+1 deleted[cancelled_list] ->spin_unlockShow less

In the Linux kernel, the following vulnerability has been resolved: phy: qcom-qmp: fix reset-controller leak on probe errors Make sure to release the lane reset controller in case of a late probe error (e.g. probe deferral). Note that due to the reset controller being defined in devicetree in "lane" child nodes, devm_reset_control_get_exclusive() cannot be used directly.Show less

In the Linux kernel, the following vulnerability has been resolved: um: Fix out-of-bounds read in LDT setup syscall_stub_data() expects the data_count parameter to be the number of longs, not bytes. ================================================================== BUG: KASAN: stack-out-of-bounds in syscall_stub_data+0x70/0xe0 Read of size 128 at addr 000000006411f6f0 by task swapper/1 CPU: 0 PID: 1 Comm: swapper Not tainted 5.18.0+ #18 Call Trace: show_stack.cold+0x166/0x2a7 __dump_stack+0x3a/0x43 dump_stack_lvl+0x1f/0x27 print_report.cold+0xdb/0xf81 kasan_report+0x119/0x1f0 kasan_check_range+0x3a3/0x440 memcpy+0x52/0x140 syscall_stub_data+0x70/0xe0 write_ldt_entry+0xac/0x190 init_new_ldt+0x515/0x960 init_new_context+0x2c4/0x4d0 mm_init.constprop.0+0x5ed/0x760 mm_alloc+0x118/0x170 0x60033f48 do_one_initcall+0x1d7/0x860 0x60003e7b kernel_init+0x6e/0x3d4 new_thread_handler+0x1e7/0x2c0 The buggy address belongs to stack of task swapper/1 and is located at offset 64 in frame: init_new_ldt+0x0/0x960 This frame has 2 objects: [32, 40) 'addr' [64, 80) 'desc' ==================================================================Show less

In the Linux kernel, the following vulnerability has been resolved: blk-iolatency: Fix inflight count imbalances and IO hangs on offline iolatency needs to track the number of inflight IOs per cgroup. As this tracking can be expensive, it is disabled when no cgroup has iolatency configured for the device. To ensure that the inflight counters stay balanced, iolatency_set_limit() freezes the request_queue while manipulating the enabled counter, which ensures that no IO is in flight and thus all counters are zero. Unfortunately, iolatency_set_limit() isn't the only place where the enabled counter is manipulated. iolatency_pd_offline() can also dec the counter and trigger disabling. As this disabling happens without freezing the q, this can easily happen while some IOs are in flight and thus leak the counts. This can be easily demonstrated by turning on iolatency on an one empty cgroup while IOs are in flight in other cgroups and then removing the cgroup. Note that iolatency shouldn't have been enabled elsewhere in the system to ensure that removing the cgroup disables iolatency for the whole device. The following keeps flipping on and off iolatency on sda: echo +io > /sys/fs/cgroup/cgroup.subtree_control while true; do mkdir -p /sys/fs/cgroup/test echo '8:0 target=100000' > /sys/fs/cgroup/test/io.latency sleep 1 rmdir /sys/fs/cgroup/test sleep 1 done and there's concurrent fio generating direct rand reads: fio --name test --filename=/dev/sda --direct=1 --rw=randread \ --runtime=600 --time_based --iodepth=256 --numjobs=4 --bs=4k while monitoring with the following drgn script: while True: for css in css_for_each_descendant_pre(prog['blkcg_root'].css.address_of_()): for pos in hlist_for_each(container_of(css, 'struct blkcg', 'css').blkg_list): blkg = container_of(pos, 'struct blkcg_gq', 'blkcg_node') pd = blkg.pd[prog['blkcg_policy_iolatency'].plid] if pd.value_() == 0: continue iolat = container_of(pd, 'struct iolatency_grp', 'pd') inflight = iolat.rq_wait.inflight.counter.value_() if inflight: print(f'inflight={inflight} {disk_name(blkg.q.disk).decode("utf-8")} ' f'{cgroup_path(css.cgroup).decode("utf-8")}') time.sleep(1) The monitoring output looks like the following: inflight=1 sda /user.slice inflight=1 sda /user.slice ... inflight=14 sda /user.slice inflight=13 sda /user.slice inflight=17 sda /user.slice inflight=15 sda /user.slice inflight=18 sda /user.slice inflight=17 sda /user.slice inflight=20 sda /user.slice inflight=19 sda /user.slice <- fio stopped, inflight stuck at 19 inflight=19 sda /user.slice inflight=19 sda /user.slice If a cgroup with stuck inflight ends up getting throttled, the throttled IOs will never get issued as there's no completion event to wake it up leading to an indefinite hang. This patch fixes the bug by unifying enable handling into a work item which is automatically kicked off from iolatency_set_min_lat_nsec() which is called from both iolatency_set_limit() and iolatency_pd_offline() paths. Punting to a work item is necessary as iolatency_pd_offline() is called under spinlocks while freezing a request_queue requires a sleepable context. This also simplifies the code reducing LOC sans the comments and avoids the unnecessary freezes which were happening whenever a cgroup's latency target is newly set or cleared.Show less

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: fix list iterator in fastrpc_req_mem_unmap_impl This is another instance of incorrect use of list iterator and checking it for NULL. The list iterator value 'map' will *always* be set and non-NULL by list_for_each_entry(), so it is incorrect to assume that the iterator value will be NULL if the list is empty (in this case, the check 'if (!map) {' will always be false and never exit as expected). To fix the bug, use a new variable 'iter' as the list iterator, while use the original variable 'map' as a dedicated pointer to point to the found element. Without this patch, Kernel crashes with below trace: Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000ffff7fb03750 ... Call trace: fastrpc_map_create+0x70/0x290 [fastrpc] fastrpc_req_mem_map+0xf0/0x2dc [fastrpc] fastrpc_device_ioctl+0x138/0xc60 [fastrpc] __arm64_sys_ioctl+0xa8/0xec invoke_syscall+0x48/0x114 el0_svc_common.constprop.0+0xd4/0xfc do_el0_svc+0x28/0x90 el0_svc+0x3c/0x130 el0t_64_sync_handler+0xa4/0x130 el0t_64_sync+0x18c/0x190 Code: 14000016 f94000a5 eb05029f 54000260 (b94018a6) ---[ end trace 0000000000000000 ]---Show less

In the Linux kernel, the following vulnerability has been resolved: serial: 8250_aspeed_vuart: Fix potential NULL dereference in aspeed_vuart_probe platform_get_resource() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference.Show less

In the Linux kernel, the following vulnerability has been resolved: remoteproc: mtk_scp: Fix a potential double free 'scp->rproc' is allocated using devm_rproc_alloc(), so there is no need to free it explicitly in the remove function.Show less

In the Linux kernel, the following vulnerability has been resolved: macsec: fix UAF bug for real_dev Create a new macsec device but not get reference to real_dev. That can not ensure that real_dev is freed after macsec. That will trigger the UAF bug for real_dev as following: ================================================================== BUG: KASAN: use-after-free in macsec_get_iflink+0x5f/0x70 drivers/net/macsec.c:3662 Call Trace: ... macsec_get_iflink+0x5f/0x70 drivers/net/macsec.c:3662 dev_get_iflink+0x73/0xe0 net/core/dev.c:637 default_operstate net/core/link_watch.c:42 [inline] rfc2863_policy+0x233/0x2d0 net/core/link_watch.c:54 linkwatch_do_dev+0x2a/0x150 net/core/link_watch.c:161 Allocated by task 22209: ... alloc_netdev_mqs+0x98/0x1100 net/core/dev.c:10549 rtnl_create_link+0x9d7/0xc00 net/core/rtnetlink.c:3235 veth_newlink+0x20e/0xa90 drivers/net/veth.c:1748 Freed by task 8: ... kfree+0xd6/0x4d0 mm/slub.c:4552 kvfree+0x42/0x50 mm/util.c:615 device_release+0x9f/0x240 drivers/base/core.c:2229 kobject_cleanup lib/kobject.c:673 [inline] kobject_release lib/kobject.c:704 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x540 lib/kobject.c:721 netdev_run_todo+0x72e/0x10b0 net/core/dev.c:10327 After commit faab39f63c1f ("net: allow out-of-order netdev unregistration") and commit e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"), we can add dev_hold_track() in macsec_dev_init() and dev_put_track() in macsec_free_netdev() to fix the problem.Show less