Loop with Unreachable Exit Condition ('Infinite Loop')

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_api: fix possible infinite loop in tcf_idr_check_alloc() syzbot found hanging tasks waiting on rtnl_lock [1] A reproducer is available in the syzbot bug. When a request to add multiple actions with the same index is sent, the second request will block forever on the first request. This holds rtnl_lock, and causes tasks to hang. Return -EAGAIN to prevent infinite looping, while keeping documented behavior. [1] INFO: task kworker/1:0:5088 blocked for more than 143 seconds. Not tainted 6.9.0-rc4-syzkaller-00173-g3cdb45594619 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:0 state:D stack:23744 pid:5088 tgid:5088 ppid:2 flags:0x00004000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: <TASK> context_switch kernel/sched/core.c:5409 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6838 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6895 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 wiphy_lock include/net/cfg80211.h:5953 [inline] reg_leave_invalid_chans net/wireless/reg.c:2466 [inline] reg_check_chans_work+0x10a/0x10e0 net/wireless/reg.c:2481Show less

A Denial of Service (DoS) vulnerability exists in the jaraco/zipp library, affecting all versions prior to 3.19.1. The vulnerability is triggered when processing a specially crafted zip file that leads to an infinite loop. This issue also impacts the zipfile module of CPython, as features from the third-party zipp library are later merged into CPython, and the affected code is identical in both projects. The infinite loop can be initiated through the use of functions affecting the `Path` module in both zipp and zipfile, such as `joinpath`, the overloaded division operator, and `iterdir`. Although the infinite loop is not resource exhaustive, it prevents the application from responding. The vulnerability was addressed in version 3.19.1 of jaraco/zipp.Show less

A vulnerability in aimhubio/aim version 3.19.3 allows an attacker to cause an infinite loop by configuring the remote tracking server to point at itself. This results in the server endlessly connecting to itself, rendering it unable to respond to other connections.Show less

In Splunk Enterprise versions below 9.2.2, 9.1.5, and 9.0.10 and Splunk Cloud Platform versions below 9.2.2403.100, an authenticated, low-privileged user that does not hold the admin or power Splunk roles could send a specially crafted HTTP POST request to the datamodel/web REST endpoint in Splunk Enterprise, potentially causing a denial of service.Show less

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: Fix loop termination condition in gss_free_in_token_pages() The in_token->pages[] array is not NULL terminated. This results in the following KASAN splat: KASAN: maybe wild-memory-access in range [0x04a2013400000008-0x04a201340000000f]Show less

In the Linux kernel, the following vulnerability has been resolved: PCI: pciehp: Fix infinite loop in IRQ handler upon power fault The Power Fault Detected bit in the Slot Status register differs from all other hotplug events in that it is sticky: It can only be cleared after turning off slot power. Per PCIe r5.0, sec. 6.7.1.8: If a power controller detects a main power fault on the hot-plug slot, it must automatically set its internal main power fault latch [...]. The main power fault latch is cleared when software turns off power to the hot-plug slot. The stickiness used to cause interrupt storms and infinite loops which were fixed in 2009 by commits 5651c48cfafe ("PCI pciehp: fix power fault interrupt storm problem") and 99f0169c17f3 ("PCI: pciehp: enable software notification on empty slots"). Unfortunately in 2020 the infinite loop issue was inadvertently reintroduced by commit 8edf5332c393 ("PCI: pciehp: Fix MSI interrupt race"): The hardirq handler pciehp_isr() clears the PFD bit until pciehp's power_fault_detected flag is set. That happens in the IRQ thread pciehp_ist(), which never learns of the event because the hardirq handler is stuck in an infinite loop. Fix by setting the power_fault_detected flag already in the hardirq handler.Show less

A vulnerability has been found in GPAC 2.5-DEV-rev228-g11067ea92-master and classified as problematic. Affected by this vulnerability is the function isoffin_process of the file src/filters/isoffin_read.c of the component MP4Box. The manipulation leads to infinite loop. It is possible to launch the attack on the local host. The exploit has been disclosed to the public and may be used. The identifier of the patch is 20c0f29139a82779b86453ce7f68d0681ec7624c. It is recommended to apply a patch to fix this issue. The identifier VDB-268789 was assigned to this vulnerability.Show less

Deep Sea Electronics DSE855 Multipart Boundary Infinite Loop Denial-of-Service Vulnerability. This vulnerability allows network-adjacent attackers to create a denial-of-service condition on affected installations of Deep Sea Electronics DSE855 devices. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of multipart boundaries. The issue results from a logic error that can lead to an infinite loop. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-23171.Show less

A vulnerability has been identified in SIMATIC CP 1542SP-1 (6GK7542-6UX00-0XE0) (All versions < V2.3), SIMATIC CP 1542SP-1 IRC (6GK7542-6VX00-0XE0) (All versions < V2.3), SIMATIC CP 1543SP-1 (6GK7543-6WX00-0XE0) (All versions < V2.3), SIPLUS ET 200SP CP 1542SP-1 IRC TX RAIL (6AG2542-6VX00-4XE0) (All versions < V2.3), SIPLUS ET 200SP CP 1543SP-1 ISEC (6AG1543-6WX00-7XE0) (All versions < V2.3), SIPLUS ET 200SP CP 1543SP-1 ISEC TX RAIL (6AG2543-6WX00-4XE0) (All versions < V2.3), SIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0) (All versions < V2.4.8), TIM 1531 IRC (6GK7543-1MX00-0XE0) (All versions < V2.4.8). The web server of affected products, if configured to allow the import of PKCS12 containers, could end up in an infinite loop when processing incomplete certificate chains. This could allow an authenticated remote attacker to create a denial of service condition by importing specially crafted PKCS12 containers.Show less

In the Linux kernel, the following vulnerability has been resolved: mptcp: fix possible stall on recvmsg() recvmsg() can enter an infinite loop if the caller provides the MSG_WAITALL, the data present in the receive queue is not sufficient to fulfill the request, and no more data is received by the peer. When the above happens, mptcp_wait_data() will always return with no wait, as the MPTCP_DATA_READY flag checked by such function is set and never cleared in such code path. Leveraging the above syzbot was able to trigger an RCU stall: rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=0af/1/0x4000000000000000 softirq=10678/10678 fqs=1 (t=10500 jiffies g=13089 q=109) rcu: rcu_preempt kthread starved for 10497 jiffies! g13089 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4955 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6236 schedule+0xd3/0x270 kernel/sched/core.c:6315 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8510 Comm: syz-executor827 Not tainted 5.15.0-rc2-next-20210920-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0xc8/0x180 mm/kasan/generic.c:189 Code: 38 00 74 ed 48 8d 50 08 eb 09 48 83 c0 01 48 39 d0 74 7a 80 38 00 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 <48> 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 80 38 00 RSP: 0018:ffffc9000cd676c8 EFLAGS: 00000283 RAX: ffffed100e9a110e RBX: ffffed100e9a110f RCX: ffffffff88ea062a RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888074d08870 RBP: ffffed100e9a110e R08: 0000000000000001 R09: ffff888074d08877 R10: ffffed100e9a110e R11: 0000000000000000 R12: ffff888074d08000 R13: ffff888074d08000 R14: ffff888074d08088 R15: ffff888074d08000 FS: 0000555556d8e300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 S: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000180 CR3: 0000000068909000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:101 [inline] test_and_clear_bit include/asm-generic/bitops/instrumented-atomic.h:83 [inline] mptcp_release_cb+0x14a/0x210 net/mptcp/protocol.c:3016 release_sock+0xb4/0x1b0 net/core/sock.c:3204 mptcp_wait_data net/mptcp/protocol.c:1770 [inline] mptcp_recvmsg+0xfd1/0x27b0 net/mptcp/protocol.c:2080 inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:659 sock_recvmsg_nosec net/socket.c:944 [inline] ____sys_recvmsg+0x527/0x600 net/socket.c:2626 ___sys_recvmsg+0x127/0x200 net/socket.c:2670 do_recvmmsg+0x24d/0x6d0 net/socket.c:2764 __sys_recvmmsg net/socket.c:2843 [inline] __do_sys_recvmmsg net/socket.c:2866 [inline] __se_sys_recvmmsg net/socket.c:2859 [inline] __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2859 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc200d2 ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: ext4: add error checking to ext4_ext_replay_set_iblocks() If the call to ext4_map_blocks() fails due to an corrupted file system, ext4_ext_replay_set_iblocks() can get stuck in an infinite loop. This could be reproduced by running generic/526 with a file system that has inline_data and fast_commit enabled. The system will repeatedly log to the console: EXT4-fs warning (device dm-3): ext4_block_to_path:105: block 1074800922 > max in inode 131076 and the stack that it gets stuck in is: ext4_block_to_path+0xe3/0x130 ext4_ind_map_blocks+0x93/0x690 ext4_map_blocks+0x100/0x660 skip_hole+0x47/0x70 ext4_ext_replay_set_iblocks+0x223/0x440 ext4_fc_replay_inode+0x29e/0x3b0 ext4_fc_replay+0x278/0x550 do_one_pass+0x646/0xc10 jbd2_journal_recover+0x14a/0x270 jbd2_journal_load+0xc4/0x150 ext4_load_journal+0x1f3/0x490 ext4_fill_super+0x22d4/0x2c00 With this patch, generic/526 still fails, but system is no longer locking up in a tight loop. It's likely the root casue is that fast_commit replay is corrupting file systems with inline_data, and we probably need to add better error handling in the fast commit replay code path beyond what is done here, which essentially just breaks the infinite loop without reporting the to the higher levels of the code.Show less

In the Linux kernel, the following vulnerability has been resolved: batman-adv: Avoid infinite loop trying to resize local TT If the MTU of one of an attached interface becomes too small to transmit the local translation table then it must be resized to fit inside all fragments (when enabled) or a single packet. But if the MTU becomes too low to transmit even the header + the VLAN specific part then the resizing of the local TT will never succeed. This can for example happen when the usable space is 110 bytes and 11 VLANs are on top of batman-adv. In this case, at least 116 byte would be needed. There will just be an endless spam of batman_adv: batadv0: Forced to purge local tt entries to fit new maximum fragment MTU (110) in the log but the function will never finish. Problem here is that the timeout will be halved all the time and will then stagnate at 0 and therefore never be able to reduce the table even more. There are other scenarios possible with a similar result. The number of BATADV_TT_CLIENT_NOPURGE entries in the local TT can for example be too high to fit inside a packet. Such a scenario can therefore happen also with only a single VLAN + 7 non-purgable addresses - requiring at least 120 bytes. While this should be handled proactively when: * interface with too low MTU is added * VLAN is added * non-purgeable local mac is added * MTU of an attached interface is reduced * fragmentation setting gets disabled (which most likely requires dropping attached interfaces) not all of these scenarios can be prevented because batman-adv is only consuming events without the the possibility to prevent these actions (non-purgable MAC address added, MTU of an attached interface is reduced). It is therefore necessary to also make sure that the code is able to handle also the situations when there were already incompatible system configuration are present.Show less

In the Linux kernel, the following vulnerability has been resolved: virtio_net: Do not send RSS key if it is not supported There is a bug when setting the RSS options in virtio_net that can break the whole machine, getting the kernel into an infinite loop. Running the following command in any QEMU virtual machine with virtionet will reproduce this problem: # ethtool -X eth0 hfunc toeplitz This is how the problem happens: 1) ethtool_set_rxfh() calls virtnet_set_rxfh() 2) virtnet_set_rxfh() calls virtnet_commit_rss_command() 3) virtnet_commit_rss_command() populates 4 entries for the rss scatter-gather 4) Since the command above does not have a key, then the last scatter-gatter entry will be zeroed, since rss_key_size == 0. sg_buf_size = vi->rss_key_size; 5) This buffer is passed to qemu, but qemu is not happy with a buffer with zero length, and do the following in virtqueue_map_desc() (QEMU function): if (!sz) { virtio_error(vdev, "virtio: zero sized buffers are not allowed"); 6) virtio_error() (also QEMU function) set the device as broken vdev->broken = true; 7) Qemu bails out, and do not repond this crazy kernel. 8) The kernel is waiting for the response to come back (function virtnet_send_command()) 9) The kernel is waiting doing the following : while (!virtqueue_get_buf(vi->cvq, &tmp) && !virtqueue_is_broken(vi->cvq)) cpu_relax(); 10) None of the following functions above is true, thus, the kernel loops here forever. Keeping in mind that virtqueue_is_broken() does not look at the qemu `vdev->broken`, so, it never realizes that the vitio is broken at QEMU side. Fix it by not sending RSS commands if the feature is not available in the device.Show less

Vitess is a database clustering system for horizontal scaling of MySQL. When executing the following simple query, the `vtgate` will go into an endless loop that also keeps consuming memory and eventually will run out of memory. This vulnerability is fixed in 19.0.4, 18.0.5, and 17.0.7.Show less