CVE Database

A vulnerability was found in Undertow where the ProxyProtocolReadListener reuses the same StringBuilder instance across multiple requests. This issue occurs when the parseProxyProtocolV1 method processes multiple requests on the same HTTP connection. As a result, different requests may share the same StringBuilder instance, potentially leading to information leakage between requests or responses. In some cases, a value from a previous request or response may be erroneously reused, which could lead to unintended data exposure. This issue primarily results in errors and connection termination but creates a risk of data leakage in multi-request environments.

In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: Fix race between namespace cleanup and gc in the list:set type Lion Ackermann reported that there is a race condition between namespace cleanup in ipset and the garbage collection of the list:set type. The namespace cleanup can destroy the list:set type of sets while the gc of the set type is waiting to run in rcu cleanup. The latter uses data from the destroyed set which thus leads use after free. The patch contains the following parts: - When destroying all sets, first remove the garbage collectors, then wait if needed and then destroy the sets. - Fix the badly ordered "wait then remove gc" for the destroy a single set case. - Fix the missing rcu locking in the list:set type in the userspace test case. - Use proper RCU list handlings in the list:set type. The patch depends on c1193d9bbbd3 (netfilter: ipset: Add list flush to cancel_gc).

A security regression (CVE-2006-5051) was discovered in OpenSSH's server (sshd). There is a race condition which can lead sshd to handle some signals in an unsafe manner. An unauthenticated, remote attacker may be able to trigger it by failing to authenticate within a set time period.

In the Linux kernel, the following vulnerability has been resolved: gpiolib: cdev: Fix use after free in lineinfo_changed_notify The use-after-free issue occurs as follows: when the GPIO chip device file is being closed by invoking gpio_chrdev_release(), watched_lines is freed by bitmap_free(), but the unregistration of lineinfo_changed_nb notifier chain failed due to waiting write rwsem. Additionally, one of the GPIO chip's lines is also in the release process and holds the notifier chain's read rwsem. Consequently, a race condition leads to the use-after-free of watched_lines. Here is the typical stack when issue happened: [free] gpio_chrdev_release() --> bitmap_free(cdev->watched_lines) <-- freed --> blocking_notifier_chain_unregister() --> down_write(&nh->rwsem) <-- waiting rwsem --> __down_write_common() --> rwsem_down_write_slowpath() --> schedule_preempt_disabled() --> schedule() [use] st54spi_gpio_dev_release() --> gpio_free() --> gpiod_free() --> gpiod_free_commit() --> gpiod_line_state_notify() --> blocking_notifier_call_chain() --> down_read(&nh->rwsem); <-- held rwsem --> notifier_call_chain() --> lineinfo_changed_notify() --> test_bit(xxxx, cdev->watched_lines) <-- use after free The side effect of the use-after-free issue is that a GPIO line event is being generated for userspace where it shouldn't. However, since the chrdev is being closed, userspace won't have the chance to read that event anyway. To fix the issue, call the bitmap_free() function after the unregistration of lineinfo_changed_nb notifier chain.

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Fix race between aio_cancel() and AIO request complete FFS based applications can utilize the aio_cancel() callback to dequeue pending USB requests submitted to the UDC. There is a scenario where the FFS application issues an AIO cancel call, while the UDC is handling a soft disconnect. For a DWC3 based implementation, the callstack looks like the following: DWC3 Gadget FFS Application dwc3_gadget_soft_disconnect() ... --> dwc3_stop_active_transfers() --> dwc3_gadget_giveback(-ESHUTDOWN) --> ffs_epfile_async_io_complete() ffs_aio_cancel() --> usb_ep_free_request() --> usb_ep_dequeue() There is currently no locking implemented between the AIO completion handler and AIO cancel, so the issue occurs if the completion routine is running in parallel to an AIO cancel call coming from the FFS application. As the completion call frees the USB request (io_data->req) the FFS application is also referencing it for the usb_ep_dequeue() call. This can lead to accessing a stale/hanging pointer. commit b566d38857fc ("usb: gadget: f_fs: use io_data->status consistently") relocated the usb_ep_free_request() into ffs_epfile_async_io_complete(). However, in order to properly implement locking to mitigate this issue, the spinlock can't be added to ffs_epfile_async_io_complete(), as usb_ep_dequeue() (if successfully dequeuing a USB request) will call the function driver's completion handler in the same context. Hence, leading into a deadlock. Fix this issue by moving the usb_ep_free_request() back to ffs_user_copy_worker(), and ensuring that it explicitly sets io_data->req to NULL after freeing it within the ffs->eps_lock. This resolves the race condition above, as the ffs_aio_cancel() routine will not continue attempting to dequeue a request that has already been freed, or the ffs_user_copy_work() not freeing the USB request until the AIO cancel is done referencing it. This fix depends on commit b566d38857fc ("usb: gadget: f_fs: use io_data->status consistently")

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: flush pending destroy work before exit_net release Similar to 2c9f0293280e ("netfilter: nf_tables: flush pending destroy work before netlink notifier") to address a race between exit_net and the destroy workqueue. The trace below shows an element to be released via destroy workqueue while exit_net path (triggered via module removal) has already released the set that is used in such transaction. [ 1360.547789] BUG: KASAN: slab-use-after-free in nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.547861] Read of size 8 at addr ffff888140500cc0 by task kworker/4:1/152465 [ 1360.547870] CPU: 4 PID: 152465 Comm: kworker/4:1 Not tainted 6.8.0+ #359 [ 1360.547882] Workqueue: events nf_tables_trans_destroy_work [nf_tables] [ 1360.547984] Call Trace: [ 1360.547991] <TASK> [ 1360.547998] dump_stack_lvl+0x53/0x70 [ 1360.548014] print_report+0xc4/0x610 [ 1360.548026] ? __virt_addr_valid+0xba/0x160 [ 1360.548040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 1360.548054] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548176] kasan_report+0xae/0xe0 [ 1360.548189] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548312] nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables] [ 1360.548447] ? __pfx_nf_tables_trans_destroy_work+0x10/0x10 [nf_tables] [ 1360.548577] ? _raw_spin_unlock_irq+0x18/0x30 [ 1360.548591] process_one_work+0x2f1/0x670 [ 1360.548610] worker_thread+0x4d3/0x760 [ 1360.548627] ? __pfx_worker_thread+0x10/0x10 [ 1360.548640] kthread+0x16b/0x1b0 [ 1360.548653] ? __pfx_kthread+0x10/0x10 [ 1360.548665] ret_from_fork+0x2f/0x50 [ 1360.548679] ? __pfx_kthread+0x10/0x10 [ 1360.548690] ret_from_fork_asm+0x1a/0x30 [ 1360.548707] </TASK> [ 1360.548719] Allocated by task 192061: [ 1360.548726] kasan_save_stack+0x20/0x40 [ 1360.548739] kasan_save_track+0x14/0x30 [ 1360.548750] __kasan_kmalloc+0x8f/0xa0 [ 1360.548760] __kmalloc_node+0x1f1/0x450 [ 1360.548771] nf_tables_newset+0x10c7/0x1b50 [nf_tables] [ 1360.548883] nfnetlink_rcv_batch+0xbc4/0xdc0 [nfnetlink] [ 1360.548909] nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink] [ 1360.548927] netlink_unicast+0x367/0x4f0 [ 1360.548935] netlink_sendmsg+0x34b/0x610 [ 1360.548944] ____sys_sendmsg+0x4d4/0x510 [ 1360.548953] ___sys_sendmsg+0xc9/0x120 [ 1360.548961] __sys_sendmsg+0xbe/0x140 [ 1360.548971] do_syscall_64+0x55/0x120 [ 1360.548982] entry_SYSCALL_64_after_hwframe+0x55/0x5d [ 1360.548994] Freed by task 192222: [ 1360.548999] kasan_save_stack+0x20/0x40 [ 1360.549009] kasan_save_track+0x14/0x30 [ 1360.549019] kasan_save_free_info+0x3b/0x60 [ 1360.549028] poison_slab_object+0x100/0x180 [ 1360.549036] __kasan_slab_free+0x14/0x30 [ 1360.549042] kfree+0xb6/0x260 [ 1360.549049] __nft_release_table+0x473/0x6a0 [nf_tables] [ 1360.549131] nf_tables_exit_net+0x170/0x240 [nf_tables] [ 1360.549221] ops_exit_list+0x50/0xa0 [ 1360.549229] free_exit_list+0x101/0x140 [ 1360.549236] unregister_pernet_operations+0x107/0x160 [ 1360.549245] unregister_pernet_subsys+0x1c/0x30 [ 1360.549254] nf_tables_module_exit+0x43/0x80 [nf_tables] [ 1360.549345] __do_sys_delete_module+0x253/0x370 [ 1360.549352] do_syscall_64+0x55/0x120 [ 1360.549360] entry_SYSCALL_64_after_hwframe+0x55/0x5d (gdb) list *__nft_release_table+0x473 0x1e033 is in __nft_release_table (net/netfilter/nf_tables_api.c:11354). 11349 list_for_each_entry_safe(flowtable, nf, &table->flowtables, list) { 11350 list_del(&flowtable->list); 11351 nft_use_dec(&table->use); 11352 nf_tables_flowtable_destroy(flowtable); 11353 } 11354 list_for_each_entry_safe(set, ns, &table->sets, list) { 11355 list_del(&set->list); 11356 nft_use_dec(&table->use); 11357 if (set->flags & (NFT_SET_MAP | NFT_SET_OBJECT)) 11358 nft_map_deactivat ---truncated---

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get() nft_unregister_flowtable_type() within nf_flow_inet_module_exit() can concurrent with __nft_flowtable_type_get() within nf_tables_newflowtable(). And thhere is not any protection when iterate over nf_tables_flowtables list in __nft_flowtable_type_get(). Therefore, there is pertential data-race of nf_tables_flowtables list entry. Use list_for_each_entry_rcu() to iterate over nf_tables_flowtables list in __nft_flowtable_type_get(), and use rcu_read_lock() in the caller nft_flowtable_type_get() to protect the entire type query process.

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: Fix potential data-race in __nft_expr_type_get() nft_unregister_expr() can concurrent with __nft_expr_type_get(), and there is not any protection when iterate over nf_tables_expressions list in __nft_expr_type_get(). Therefore, there is potential data-race of nf_tables_expressions list entry. Use list_for_each_entry_rcu() to iterate over nf_tables_expressions list in __nft_expr_type_get(), and use rcu_read_lock() in the caller nft_expr_type_get() to protect the entire type query process.

In the Linux kernel, the following vulnerability has been resolved: mm: swap: fix race between free_swap_and_cache() and swapoff() There was previously a theoretical window where swapoff() could run and teardown a swap_info_struct while a call to free_swap_and_cache() was running in another thread. This could cause, amongst other bad possibilities, swap_page_trans_huge_swapped() (called by free_swap_and_cache()) to access the freed memory for swap_map. This is a theoretical problem and I haven't been able to provoke it from a test case. But there has been agreement based on code review that this is possible (see link below). Fix it by using get_swap_device()/put_swap_device(), which will stall swapoff(). There was an extra check in _swap_info_get() to confirm that the swap entry was not free. This isn't present in get_swap_device() because it doesn't make sense in general due to the race between getting the reference and swapoff. So I've added an equivalent check directly in free_swap_and_cache(). Details of how to provoke one possible issue (thanks to David Hildenbrand for deriving this): --8<----- __swap_entry_free() might be the last user and result in "count == SWAP_HAS_CACHE". swapoff->try_to_unuse() will stop as soon as soon as si->inuse_pages==0. So the question is: could someone reclaim the folio and turn si->inuse_pages==0, before we completed swap_page_trans_huge_swapped(). Imagine the following: 2 MiB folio in the swapcache. Only 2 subpages are still references by swap entries. Process 1 still references subpage 0 via swap entry. Process 2 still references subpage 1 via swap entry. Process 1 quits. Calls free_swap_and_cache(). -> count == SWAP_HAS_CACHE [then, preempted in the hypervisor etc.] Process 2 quits. Calls free_swap_and_cache(). -> count == SWAP_HAS_CACHE Process 2 goes ahead, passes swap_page_trans_huge_swapped(), and calls __try_to_reclaim_swap(). __try_to_reclaim_swap()->folio_free_swap()->delete_from_swap_cache()-> put_swap_folio()->free_swap_slot()->swapcache_free_entries()-> swap_entry_free()->swap_range_free()-> ... WRITE_ONCE(si->inuse_pages, si->inuse_pages - nr_entries); What stops swapoff to succeed after process 2 reclaimed the swap cache but before process1 finished its call to swap_page_trans_huge_swapped()? --8<-----

In the Linux kernel, the following vulnerability has been resolved: vfio/pci: Lock external INTx masking ops Mask operations through config space changes to DisINTx may race INTx configuration changes via ioctl. Create wrappers that add locking for paths outside of the core interrupt code. In particular, irq_type is updated holding igate, therefore testing is_intx() requires holding igate. For example clearing DisINTx from config space can otherwise race changes of the interrupt configuration. This aligns interfaces which may trigger the INTx eventfd into two camps, one side serialized by igate and the other only enabled while INTx is configured. A subsequent patch introduces synchronization for the latter flows.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: Add mutex lock in control vblank irq Add a mutex lock to control vblank irq to synchronize vblank enable/disable operations happening from different threads to prevent race conditions while registering/unregistering the vblank irq callback. v4: -Removed vblank_ctl_lock from dpu_encoder_virt, so it is only a parameter of dpu_encoder_phys. -Switch from atomic refcnt to a simple int counter as mutex has now been added v3: Mistakenly did not change wording in last version. It is done now. v2: Slightly changed wording of commit message Patchwork: https://patchwork.freedesktop.org/patch/571854/