CVE Database
Synced from NVD, cross-referenced against CISA KEV and EPSS · ordered by last update
| CVE ID | Score | Description |
|---|---|---|
| 2mo ago | 7.5 | In the Linux kernel, the following vulnerability has been resolved: net: ks8851: Reinstate disabling of BHs around IRQ handler If the driver executes ks8851_irq() AND a TX packet has been sent, then the driver enables TX queue via netif_wake_queue() which schedules TX softirq to queue packets for this device. If CONFIG_PREEMPT_RT=y is set AND a packet has also been received by the MAC, then ks8851_rx_pkts() calls netdev_alloc_skb_ip_align() to allocate SKBs for the received packets. If netdev_alloc_skb_ip_align() is called with BH enabled, then local_bh_enable() at the end of netdev_alloc_skb_ip_align() will trigger the pending softirq processing, which may ultimately call the .xmit callback ks8851_start_xmit_par(). The ks8851_start_xmit_par() will try to lock struct ks8851_net_par .lock spinlock, which is already locked by ks8851_irq() from which ks8851_start_xmit_par() was called. This leads to a deadlock, which is reported by the kernel, including a trace listed below. If CONFIG_PREEMPT_RT is not set, then since commit 0913ec336a6c0 ("net: ks8851: Fix deadlock with the SPI chip variant") the deadlock can also be triggered without received packet in the RX FIFO. The pending softirqs will be processed on return from spin_unlock_bh(&ks->statelock) in ks8851_irq(), which triggers the deadlock as well. Fix the problem by disabling BH around critical sections, including the IRQ handler, thus preventing the net_tx_action() softirq from triggering during these critical sections. The net_tx_action() softirq is triggered once BH are re-enabled and at the end of the IRQ handler, once all the other IRQ handler actions have been completed. __schedule from schedule_rtlock+0x1c/0x34 schedule_rtlock from rtlock_slowlock_locked+0x548/0x904 rtlock_slowlock_locked from rt_spin_lock+0x60/0x9c rt_spin_lock from ks8851_start_xmit_par+0x74/0x1a8 ks8851_start_xmit_par from netdev_start_xmit+0x20/0x44 netdev_start_xmit from dev_hard_start_xmit+0xd0/0x188 dev_hard_start_xmit from sch_direct_xmit+0xb8/0x25c sch_direct_xmit from __qdisc_run+0x1f8/0x4ec __qdisc_run from qdisc_run+0x1c/0x28 qdisc_run from net_tx_action+0x1f0/0x268 net_tx_action from handle_softirqs+0x1a4/0x270 handle_softirqs from __local_bh_enable_ip+0xcc/0xe0 __local_bh_enable_ip from __alloc_skb+0xd8/0x128 __alloc_skb from __netdev_alloc_skb+0x3c/0x19c __netdev_alloc_skb from ks8851_irq+0x388/0x4d4 ks8851_irq from irq_thread_fn+0x24/0x64 irq_thread_fn from irq_thread+0x178/0x28c irq_thread from kthread+0x12c/0x138 kthread from ret_from_fork+0x14/0x28 |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: EDAC/versalnet: Fix device_node leak in mc_probe() of_parse_phandle() returns a device_node reference that must be released with of_node_put(). The original code never freed r5_core_node on any exit path, causing a memory leak. Fix this by using the automatic cleanup attribute __free(device_node) which ensures of_node_put() is called when the variable goes out of scope. |
| 2mo ago | 7 | In the Linux kernel, the following vulnerability has been resolved: mm/slab: return NULL early from kmalloc_nolock() in NMI on UP On UP kernels (!CONFIG_SMP), spin_trylock() is a no-op that unconditionally succeeds even when the lock is already held. As a result, kmalloc_nolock() called from NMI context can re-enter the slab allocator and acquire n->list_lock that the interrupted context is already holding, corrupting slab state. With CONFIG_DEBUG_SPINLOCK on UP, the following BUG is triggered with the slub_kunit test module: BUG: spinlock trylock failure on UP on CPU#0, kunit_try_catch/243 [...] Call Trace: <NMI> dump_stack_lvl+0x3f/0x60 do_raw_spin_trylock+0x41/0x50 _raw_spin_trylock+0x24/0x50 get_from_partial_node+0x120/0x4d0 ___slab_alloc+0x8a/0x4c0 kmalloc_nolock_noprof+0x164/0x310 [...] </NMI> Fix this by returning NULL early when invoked from NMI on a UP kernel. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: crypto: algif_aead - snapshot IV for async AEAD requests AF_ALG AEAD AIO requests currently use the socket-wide IV buffer during request processing. For async requests, later socket activity can update that shared state before the original request has fully completed, which can lead to inconsistent IV handling. Snapshot the IV into per-request storage when preparing the AEAD request, so in-flight operations no longer depend on mutable socket state. |
| 2mo ago | 7.5 | In the Linux kernel, the following vulnerability has been resolved: net/smc: avoid early lgr access in smc_clc_wait_msg A CLC decline can be received while the handshake is still in an early stage, before the connection has been associated with a link group. The decline handling in smc_clc_wait_msg() updates link-group level sync state for first-contact declines, but that state only exists after link group setup has completed. Guard the link-group update accordingly and keep the per-socket peer diagnosis handling unchanged. This preserves the existing sync_err handling for established link-group contexts and avoids touching link-group state before it is available. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: net: qrtr: ns: Limit the maximum number of lookups Current code does no bound checking on the number of lookups a client can perform. Though the code restricts the lookups to local clients, there is still a possibility of a malicious local client sending a flood of NEW_LOOKUP messages over the same socket. Fix this issue by limiting the maximum number of lookups to 64 globally. Since the nameserver allows only atmost one local observer, this global lookup count will ensure that the lookups stay within the limit. Note that, limit of 64 is chosen based on the current platform requirements. If requirement changes in the future, this limit can be increased. |
| 2mo ago | 4.7 | In the Linux kernel, the following vulnerability has been resolved: mm/damon/core: fix damon_call() vs kdamond_fn() exit race Patch series "mm/damon/core: fix damon_call()/damos_walk() vs kdmond exit race". damon_call() and damos_walk() can leak memory and/or deadlock when they race with kdamond terminations. Fix those. This patch (of 2); When kdamond_fn() main loop is finished, the function cancels all remaining damon_call() requests and unset the damon_ctx->kdamond so that API callers and API functions themselves can know the context is terminated. damon_call() adds the caller's request to the queue first. After that, it shows if the kdamond of the damon_ctx is still running (damon_ctx->kdamond is set). Only if the kdamond is running, damon_call() starts waiting for the kdamond's handling of the newly added request. The damon_call() requests registration and damon_ctx->kdamond unset are protected by different mutexes, though. Hence, damon_call() could race with damon_ctx->kdamond unset, and result in deadlocks. For example, let's suppose kdamond successfully finished the damon_call() requests cancelling. Right after that, damon_call() is called for the context. It registers the new request, and shows the context is still running, because damon_ctx->kdamond unset is not yet done. Hence the damon_call() caller starts waiting for the handling of the request. However, the kdamond is already on the termination steps, so it never handles the new request. As a result, the damon_call() caller threads infinitely waits. Fix this by introducing another damon_ctx field, namely call_controls_obsolete. It is protected by the damon_ctx->call_controls_lock, which protects damon_call() requests registration. Initialize (unset) it in kdamond_fn() before letting damon_start() returns and set it just before the cancelling of remaining damon_call() requests is executed. damon_call() reads the obsolete field under the lock and avoids adding a new request. After this change, only requests that are guaranteed to be handled or cancelled are registered. Hence the after-registration DAMON context termination check is no longer needed. Remove it together. Note that the deadlock will not happen when damon_call() is called for repeat mode request. In tis case, damon_call() returns instead of waiting for the handling when the request registration succeeds and it shows the kdamond is running. However, if the request also has dealloc_on_cancel, the request memory would be leaked. The issue is found by sashiko [1]. |
| 2mo ago | 7.5 | In the Linux kernel, the following vulnerability has been resolved: libceph: Prevent potential null-ptr-deref in ceph_handle_auth_reply() If a message of type CEPH_MSG_AUTH_REPLY contains a zero value for both protocol and result, this is currently not treated as an error. In case of ac->negotiating == true and ac->protocol > 0, this leads to setting ac->protocol = 0 and ac->ops = NULL. Thereafter, the check for ac->protocol != protocol returns false, and init_protocol() is not called. Subsequently, ac->ops->handle_reply() is called, which leads to a null pointer dereference, because ac->ops is still NULL. This patch changes the check for ac->protocol != protocol to !ac->protocol, as this also includes the case when the protocol was set to zero in the message. This causes the message to be treated as containing a bad auth protocol. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: dm mirror: fix integer overflow in create_dirty_log() The argument count calculation in create_dirty_log() performs `*args_used = 2 + param_count` before validating against argc. When a user provides a param_count close to UINT_MAX via the device mapper table string, this unsigned addition wraps around to a small value, causing the subsequent `argc < *args_used` check to be bypassed. The overflowed param_count is then passed as argc to dm_dirty_log_create(), where it can cause out-of-bounds reads on the argv array. Fix by comparing param_count against argc - 2 before performing the addition, following the same pattern used by parse_features() in the same file. Since argc >= 2 is already guaranteed, the subtraction is safe. |
| 2mo ago | 7.1 | In the Linux kernel, the following vulnerability has been resolved: misc: ibmasm: fix OOB MMIO read in ibmasm_handle_mouse_interrupt() ibmasm_handle_mouse_interrupt() performs an out-of-bounds MMIO read when the queue reader or writer index from hardware exceeds REMOTE_QUEUE_SIZE (60). A compromised service processor can trigger this by writing an out-of-range value to the reader or writer MMIO register before asserting an interrupt. Since writer is re-read from hardware on every loop iteration, it can also be set to an out-of-range value after the loop has already started. The root cause is that get_queue_reader() and get_queue_writer() return raw readl() values that are passed directly into get_queue_entry(), which computes: queue_begin + reader * sizeof(struct remote_input) with no bounds check. This unchecked MMIO address is then passed to memcpy_fromio(), reading 8 bytes from unintended device registers. For sufficiently large values the address falls outside the PCI BAR mapping entirely, triggering a machine check exception. Fix by checking both indices against REMOTE_QUEUE_SIZE at the top of the loop body, before any call to get_queue_entry(). On an out-of-range value, reset the reader register to 0 via set_queue_reader() before breaking, so that normal queue operation can resume if the corrupted hardware state is transient. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: thermal: core: Fix thermal zone governor cleanup issues If thermal_zone_device_register_with_trips() fails after adding a thermal governor to the thermal zone being registered, the governor is not removed from it as appropriate which may lead to a memory leak. In turn, thermal_zone_device_unregister() calls thermal_set_governor() without acquiring the thermal zone lock beforehand which may race with a governor update via sysfs and may lead to a use-after-free in that case. Address these issues by adding two thermal_set_governor() calls, one to thermal_release() to remove the governor from the given thermal zone, and one to the thermal zone registration error path to cover failures preceding the thermal zone device registration. |
| 2mo ago | 7.1 | In the Linux kernel, the following vulnerability has been resolved: mm/damon/core: validate damos_quota_goal->nid for node_mem_{used,free}_bp Patch series "mm/damon/core: validate damos_quota_goal->nid". node_mem[cg]_{used,free}_bp DAMOS quota goals receive the node id. The node id is used for si_meminfo_node() and NODE_DATA() without proper validation. As a result, privileged users can trigger an out of bounds memory access using DAMON_SYSFS. Fix the issues. The issue was originally reported [1] with a fix by another author. The original author announced [2] that they will stop working including the fix that was still in the review stage. Hence I'm restarting this. This patch (of 2): Users can set damos_quota_goal->nid with arbitrary value for node_mem_{used,free}_bp. But DAMON core is using those for si_meminfo_node() without the validation of the value. This can result in out of bounds memory access. The issue can actually triggered using DAMON user-space tool (damo), like below. $ sudo ./damo start --damos_action stat \ --damos_quota_goal node_mem_used_bp 50% -1 \ --damos_quota_interval 1s $ sudo dmesg [...] [ 65.565986] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000098 Fix this issue by adding the validation of the given node. If an invalid node id is given, it returns 0% for used memory ratio, and 100% for free memory ratio. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: crypto: atmel-aes - Fix 3-page memory leak in atmel_aes_buff_cleanup atmel_aes_buff_init() allocates 4 pages using __get_free_pages() with ATMEL_AES_BUFFER_ORDER, but atmel_aes_buff_cleanup() frees only the first page using free_page(), leaking the remaining 3 pages. Use free_pages() with ATMEL_AES_BUFFER_ORDER to fix the memory leak. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: stop parsing UAC2 rates at MAX_NR_RATES parse_uac2_sample_rate_range() caps the number of enumerated rates at MAX_NR_RATES, but it only breaks out of the current rate loop. A malformed UAC2 RANGE response with additional triplets continues parsing the remaining triplets and repeatedly prints "invalid uac2 rates" while probe still holds register_mutex. Stop the whole parse once the cap is reached and return the number of rates collected so far. |
| 2mo ago | 4.7 | In the Linux kernel, the following vulnerability has been resolved: mm: fix deferred split queue races during migration migrate_folio_move() records the deferred split queue state from src and replays it on dst. Replaying it after remove_migration_ptes(src, dst, 0) makes dst visible before it is requeued, so a concurrent rmap-removal path can mark dst partially mapped and trip the WARN in deferred_split_folio(). Move the requeue before remove_migration_ptes() so dst is back on the deferred split queue before it becomes visible again. Because migration still holds dst locked at that point, teach deferred_split_scan() to requeue a folio when folio_trylock() fails. Otherwise a fully mapped underused folio can be dequeued by the shrinker and silently lost from split_queue. [ziy@nvidia.com: move the comment] |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: remoteproc: xlnx: Only access buffer information if IPI is buffered In the receive callback check if message is NULL to prevent possibility of crash by NULL pointer dereferencing. |
| 2mo ago | 7.8 | In the Linux kernel, the following vulnerability has been resolved: tcp: call sk_data_ready() after listener migration When inet_csk_listen_stop() migrates an established child socket from a closing listener to another socket in the same SO_REUSEPORT group, the target listener gets a new accept-queue entry via inet_csk_reqsk_queue_add(), but that path never notifies the target listener's waiters. A nonblocking accept() still works because it checks the queue directly, but poll()/epoll_wait() waiters and blocking accept() callers can also remain asleep indefinitely. Call READ_ONCE(nsk->sk_data_ready)(nsk) after a successful migration in inet_csk_listen_stop(). However, after inet_csk_reqsk_queue_add() succeeds, the ref acquired in reuseport_migrate_sock() is effectively transferred to nreq->rsk_listener. Another CPU can then dequeue nreq via accept() or listener shutdown, hit reqsk_put(), and drop that listener ref. Since listeners are SOCK_RCU_FREE, wrap the post-queue_add() dereferences of nsk in rcu_read_lock()/rcu_read_unlock(), which also covers the existing sock_net(nsk) access in that path. The reqsk_timer_handler() path does not need the same changes for two reasons: half-open requests become readable only after the final ACK, where tcp_child_process() already wakes the listener; and once nreq is visible via inet_ehash_insert(), the success path no longer touches nsk directly. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Add missing save/restore handling of LBR MSRs MSR_IA32_DEBUGCTLMSR and LBR MSRs are currently not enumerated by KVM_GET_MSR_INDEX_LIST, and LBR MSRs cannot be set with KVM_SET_MSRS. So save/restore is completely broken. Fix it by adding the MSRs to msrs_to_save_base, and allowing writes to LBR MSRs from userspace only (as they are read-only MSRs) if LBR virtualization is enabled. Additionally, to correctly restore L1's LBRs while L2 is running, make sure the LBRs are copied from the captured VMCB01 save area in svm_copy_vmrun_state(). Note, for VMX, this also fixes a flaw where MSR_IA32_DEBUGCTLMSR isn't reported as an MSR to save/restore. Note #2, over-reporting MSR_IA32_LASTxxx on Intel is ok, as KVM already handles unsupported reads and writes thanks to commit b5e2fec0ebc3 ("KVM: Ignore DEBUGCTL MSRs with no effect") (kvm_do_msr_access() will morph the unsupported userspace write into a nop). [sean: guard with lbrv checks, massage changelog] |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: mm/memfd_luo: fix physical address conversion in put_folios cleanup In memfd_luo_retrieve_folios()'s put_folios cleanup path: 1. kho_restore_folio() expects a phys_addr_t (physical address) but receives a raw PFN (pfolio->pfn). This causes kho_restore_page() to check the wrong physical address (pfn << PAGE_SHIFT instead of the actual physical address). 2. This loop lacks the !pfolio->pfn check that exists in the main retrieval loop and memfd_luo_discard_folios(), which could incorrectly process sparse file holes where pfn=0. Fix by converting PFN to physical address with PFN_PHYS() and adding the !pfolio->pfn check, matching the pattern used elsewhere in this file. This issue was identified by the AI review. https://sashiko.dev/#/patchset/20260323110747.193569-1-duanchenghao@kylinos.cn |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix memory leaks in rxkad_verify_response() Fix rxkad_verify_response() to free the ticket and the server key under all circumstances by initialising the ticket pointer to NULL and then making all paths through the function after the first allocation has been done go through a single common epilogue that just releases everything - where all the releases skip on a NULL pointer. |
| 2mo ago | 7.8 | In the Linux kernel, the following vulnerability has been resolved: media: mtk-jpeg: fix use-after-free in release path due to uncancelled work The mtk_jpeg_release() function frees the context structure (ctx) without first cancelling any pending or running work in ctx->jpeg_work. This creates a race window where the workqueue callback may still be accessing the context memory after it has been freed. Race condition: CPU 0 (release) CPU 1 (workqueue) ---------------- ------------------ close() mtk_jpeg_release() mtk_jpegenc_worker() ctx = work->data // accessing ctx kfree(ctx) // freed! access ctx // UAF! The work is queued via queue_work() during JPEG encode/decode operations (via mtk_jpeg_device_run). If the device is closed while work is pending or running, the work handler will access freed memory. Fix this by calling cancel_work_sync() BEFORE acquiring the mutex. This ordering is critical: if cancel_work_sync() is called after mutex_lock(), and the work handler also tries to acquire the same mutex, it would cause a deadlock. Note: The open error path does NOT need cancel_work_sync() because INIT_WORK() only initializes the work structure - it does not schedule it. Work is only scheduled later during ioctl operations. |
| 2mo ago | 8.1 | In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix error handling in rxgk_extract_token() Fix a missing bit of error handling in rxgk_extract_token(): in the event that rxgk_decrypt_skb() returns -ENOMEM, it should just return that rather than continuing on (for anything else, it generates an abort). |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: pci-epf-ntb: Remove duplicate resource teardown epf_ntb_epc_destroy() duplicates the teardown that the caller is supposed to do later. This leads to an oops when .allow_link fails or when .drop_link is performed. Remove the helper. Also drop pci_epc_put(). EPC device refcounting is tied to configfs EPC group lifetime, and pci_epc_put() in the .drop_link path is sufficient. |
| 2mo ago | 4.7 | In the Linux kernel, the following vulnerability has been resolved: mm/damon/core: fix damos_walk() vs kdamond_fn() exit race When kdamond_fn() main loop is finished, the function cancels remaining damos_walk() request and unset the damon_ctx->kdamond so that API callers and API functions themselves can show the context is terminated. damos_walk() adds the caller's request to the queue first. After that, it shows if the kdamond of the damon_ctx is still running (damon_ctx->kdamond is set). Only if the kdamond is running, damos_walk() starts waiting for the kdamond's handling of the newly added request. The damos_walk() requests registration and damon_ctx->kdamond unset are protected by different mutexes, though. Hence, damos_walk() could race with damon_ctx->kdamond unset, and result in deadlocks. For example, let's suppose kdamond successfully finished the damow_walk() request cancelling. Right after that, damos_walk() is called for the context. It registers the new request, and shows the context is still running, because damon_ctx->kdamond unset is not yet done. Hence the damos_walk() caller starts waiting for the handling of the request. However, the kdamond is already on the termination steps, so it never handles the new request. As a result, the damos_walk() caller thread infinitely waits. Fix this by introducing another damon_ctx field, namely walk_control_obsolete. It is protected by the damon_ctx->walk_control_lock, which protects damos_walk() request registration. Initialize (unset) it in kdamond_fn() before letting damon_start() returns and set it just before the cancelling of the remaining damos_walk() request is executed. damos_walk() reads the obsolete field under the lock and avoids adding a new request. After this change, only requests that are guaranteed to be handled or cancelled are registered. Hence the after-registration DAMON context termination check is no longer needed. Remove it together. The issue is found by sashiko [1]. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: hwmon: (powerz) Avoid cacheline sharing for DMA buffer Depending on the architecture the transfer buffer may share a cacheline with the following mutex. As the buffer may be used for DMA, that is problematic. Use the high-level DMA helpers to make sure that cacheline sharing can not happen. Also drop the comment, as the helpers are documentation enough. https://sashiko.dev/#/message/20260408175814.934BFC19421%40smtp.kernel.org |
| 2mo ago | 7.8 | In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: fix u32 overflow in pushbuf reloc bounds check nouveau_gem_pushbuf_reloc_apply() validates each relocation with if (r->reloc_bo_offset + 4 > nvbo->bo.base.size) but reloc_bo_offset is __u32 (uapi/drm/nouveau_drm.h) and the integer literal 4 promotes to unsigned int, so the addition is performed in 32 bits and wraps before the comparison against the size_t bo size. Cast to u64 so the addition happens in 64-bit arithmetic. [ Add Fixes: tag. - Danilo ] |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: xfs: fix a resource leak in xfs_alloc_buftarg() In the error path, call fs_put_dax() to drop the DAX device reference. |
| 2mo ago | 7.8 | In the Linux kernel, the following vulnerability has been resolved: ALSA: caiaq: Handle probe errors properly The probe procedure of setup_card() in caiaq driver doesn't treat the error cases gracefully, e.g. the error from snd_card_register() calls snd_card_free() but continues. This would lead to a UAF for the further calls like snd_usb_caiaq_control_init(), as Berk suggested in another patch in the link below. However, the problem is not only that; in general, this function drops the all error handlings (as it's a void function) although its caller can propagate an error to snd_probe(), which eventually calls snd_card_free() as a proper error path. That said, we should treat each error case in setup_card(), and just return the error code promptly, which is then handled later as a fatal error in snd_probe(). This patch achieves it by changing the setup_card() to return an error code. Also, the superfluous snd_card_free() call is removed, too. Note that card->private_free can be set still safely at returning an error. All called functions in card_free() have checks of the unassigned resources or NULL checks. |
| 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: net: qrtr: ns: Limit the total number of nodes Currently, the nameserver doesn't limit the number of nodes it handles. This can be an attack vector if a malicious client starts registering random nodes, leading to memory exhaustion. Hence, limit the maximum number of nodes to 64. Note that, limit of 64 is chosen based on the current platform requirements. If requirement changes in the future, this limit can be increased. |
| Exploit 2mo ago | 5.5 | In the Linux kernel, the following vulnerability has been resolved: ext2: reject inodes with zero i_nlink and valid mode in ext2_iget() ext2_iget() already rejects inodes with i_nlink == 0 when i_mode is zero or i_dtime is set, treating them as deleted. However, the case of i_nlink == 0 with a non-zero mode and zero dtime slips through. Since ext2 has no orphan list, such a combination can only result from filesystem corruption - a legitimate inode deletion always sets either i_dtime or clears i_mode before freeing the inode. A crafted image can exploit this gap to present such an inode to the VFS, which then triggers WARN_ON inside drop_nlink() (fs/inode.c) via ext2_unlink(), ext2_rename() and ext2_rmdir(): WARNING: CPU: 3 PID: 609 at fs/inode.c:336 drop_nlink+0xad/0xd0 fs/inode.c:336 CPU: 3 UID: 0 PID: 609 Comm: syz-executor Not tainted 6.12.77+ #1 Call Trace: <TASK> inode_dec_link_count include/linux/fs.h:2518 [inline] ext2_unlink+0x26c/0x300 fs/ext2/namei.c:295 vfs_unlink+0x2fc/0x9b0 fs/namei.c:4477 do_unlinkat+0x53e/0x730 fs/namei.c:4541 __x64_sys_unlink+0xc6/0x110 fs/namei.c:4587 do_syscall_64+0xf5/0x220 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> WARNING: CPU: 0 PID: 646 at fs/inode.c:336 drop_nlink+0xad/0xd0 fs/inode.c:336 CPU: 0 UID: 0 PID: 646 Comm: syz.0.17 Not tainted 6.12.77+ #1 Call Trace: <TASK> inode_dec_link_count include/linux/fs.h:2518 [inline] ext2_rename+0x35e/0x850 fs/ext2/namei.c:374 vfs_rename+0xf2f/0x2060 fs/namei.c:5021 do_renameat2+0xbe2/0xd50 fs/namei.c:5178 __x64_sys_rename+0x7e/0xa0 fs/namei.c:5223 do_syscall_64+0xf5/0x220 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> WARNING: CPU: 0 PID: 634 at fs/inode.c:336 drop_nlink+0xad/0xd0 fs/inode.c:336 CPU: 0 UID: 0 PID: 634 Comm: syz-executor Not tainted 6.12.77+ #1 Call Trace: <TASK> inode_dec_link_count include/linux/fs.h:2518 [inline] ext2_rmdir+0xca/0x110 fs/ext2/namei.c:311 vfs_rmdir+0x204/0x690 fs/namei.c:4348 do_rmdir+0x372/0x3e0 fs/namei.c:4407 __x64_sys_unlinkat+0xf0/0x130 fs/namei.c:4577 do_syscall_64+0xf5/0x220 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Extend the existing i_nlink == 0 check to also catch this case, reporting the corruption via ext2_error() and returning -EFSCORRUPTED. This rejects the inode at load time and prevents it from reaching any of the namei.c paths. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. |