In the Linux kernel, the following vulnerability has been resolved: ext4: refresh inline data size before write operations The cached ei->i_inline_size can become stale between the initial size check and when ext4_update_inline_data()/ext4_create_inline_data() use it. Although ext4_get_max_inline_size() reads the correct value at the time of the check, concurrent xattr operations can modify i_inline_size before ext4_write_lock_xattr() is acquired. This causes ext4_update_inline_data() and ext4_create_inline_data() to work with stale capacity values, leading to a BUG_ON() crash in ext4_write_inline_data(): kernel BUG at fs/ext4/inline.c:1331! BUG_ON(pos + len > EXT4_I(inode)->i_inline_size); The race window: 1. ext4_get_max_inline_size() reads i_inline_size = 60 (correct) 2. Size check passes for 50-byte write 3. [Another thread adds xattr, i_inline_size changes to 40] 4. ext4_write_lock_xattr() acquires lock 5. ext4_update_inline_data() uses stale i_inline_size = 60 6. Attempts to w...

In the Linux kernel, the following vulnerability has been resolved: ksmbd: ipc: fix use-after-free in ipc_msg_send_request ipc_msg_send_request() waits for a generic netlink reply using an ipc_msg_table_entry on the stack. The generic netlink handler (handle_generic_event()/handle_response()) fills entry->response under ipc_msg_table_lock, but ipc_msg_send_request() used to validate and free entry->response without holding the same lock. Under high concurrency this allows a race where handle_response() is copying data into entry->response while ipc_msg_send_request() has just freed it, leading to a slab-use-after-free reported by KASAN in handle_generic_event(): BUG: KASAN: slab-use-after-free in handle_generic_event+0x3c4/0x5f0 [ksmbd] Write of size 12 at addr ffff888198ee6e20 by task pool/109349 ... Freed by task: kvfree ipc_msg_send_request [ksmbd] ksmbd_rpc_open -> ksmbd_session_rpc_open [ksmbd] Fix by: - Taking ipc_msg_table_lock in ipc_msg_send_request() while validating entry...

In the Linux kernel, the following vulnerability has been resolved: crypto: zstd - fix double-free in per-CPU stream cleanup The crypto/zstd module has a double-free bug that occurs when multiple tfms are allocated and freed. The issue happens because zstd_streams (per-CPU contexts) are freed in zstd_exit() during every tfm destruction, rather than being managed at the module level. When multiple tfms exist, each tfm exit attempts to free the same shared per-CPU streams, resulting in a double-free. This leads to a stack trace similar to: BUG: Bad page state in process kworker/u16:1 pfn:106fd93 page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106fd93 flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff) page_type: 0xffffffff() raw: 0017ffffc0000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: nonzero entire_mapcount Modules linked in: ... CPU: 3 UID: 0 PID: 2...

In the Linux kernel, the following vulnerability has been resolved: ext4: add i_data_sem protection in ext4_destroy_inline_data_nolock() Fix a race between inline data destruction and block mapping. The function ext4_destroy_inline_data_nolock() changes the inode data layout by clearing EXT4_INODE_INLINE_DATA and setting EXT4_INODE_EXTENTS. At the same time, another thread may execute ext4_map_blocks(), which tests EXT4_INODE_EXTENTS to decide whether to call ext4_ext_map_blocks() or ext4_ind_map_blocks(). Without i_data_sem protection, ext4_ind_map_blocks() may receive inode with EXT4_INODE_EXTENTS flag and triggering assert. kernel BUG at fs/ext4/indirect.c:546! EXT4-fs (loop2): unmounting filesystem. invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:ext4_ind_map_blocks.cold+0x2b/0x5a fs/ext4/indirect.c:546 Call Trace: <TASK> ext4_map_blocks+0xb9b/0x16f0 fs/ext4/inode.c:681 _ext4_get_block+0x...

In the Linux kernel, the following vulnerability has been resolved: rust_binder: fix race condition on death_list Rust Binder contains the following unsafe operation: // SAFETY: A `NodeDeath` is never inserted into the death list // of any node other than its owner, so it is either in this // death list or in no death list. unsafe { node_inner.death_list.remove(self) }; This operation is unsafe because when touching the prev/next pointers of a list element, we have to ensure that no other thread is also touching them in parallel. If the node is present in the list that `remove` is called on, then that is fine because we have exclusive access to that list. If the node is not in any list, then it's also ok. But if it's present in a different list that may be accessed in parallel, then that may be a data race on the prev/next pointers. And unfortunately that is exactly what is happening here. In Node::release, we: 1. Take the lock. 2. Move all items to a local list on the stack. 3. Dro...

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Don't skip unrelated instruction if INT3/INTO is replaced When re-injecting a soft interrupt from an INT3, INT0, or (select) INTn instruction, discard the exception and retry the instruction if the code stream is changed (e.g. by a different vCPU) between when the CPU executes the instruction and when KVM decodes the instruction to get the next RIP. As effectively predicted by commit 6ef88d6e36c2 ("KVM: SVM: Re-inject INT3/INTO instead of retrying the instruction"), failure to verify that the correct INTn instruction was decoded can effectively clobber guest state due to decoding the wrong instruction and thus specifying the wrong next RIP. The bug most often manifests as "Oops: int3" panics on static branch checks in Linux guests. Enabling or disabling a static branch in Linux uses the kernel's "text poke" code patching mechanism. To modify code while other CPUs may be executing that code, Linux (tempor...

In the Linux kernel, the following vulnerability has been resolved: comedi: multiq3: sanitize config options in multiq3_attach() Syzbot identified an issue [1] in multiq3_attach() that induces a task timeout due to open() or COMEDI_DEVCONFIG ioctl operations, specifically, in the case of multiq3 driver. This problem arose when syzkaller managed to craft weird configuration options used to specify the number of channels in encoder subdevice. If a particularly great number is passed to s->n_chan in multiq3_attach() via it->options[2], then multiple calls to multiq3_encoder_reset() at the end of driver-specific attach() method will be running for minutes, thus blocking tasks and affected devices as well. While this issue is most likely not too dangerous for real-life devices, it still makes sense to sanitize configuration inputs. Enable a sensible limit on the number of encoder chips (4 chips max, each with 2 channels) to stop this behaviour from manifesting. [1] Syzbot crash: INFO: ta...

In the Linux kernel, the following vulnerability has been resolved: comedi: check device's attached status in compat ioctls Syzbot identified an issue [1] that crashes kernel, seemingly due to unexistent callback dev->get_valid_routes(). By all means, this should not occur as said callback must always be set to get_zero_valid_routes() in __comedi_device_postconfig(). As the crash seems to appear exclusively in i386 kernels, at least, judging from [1] reports, the blame lies with compat versions of standard IOCTL handlers. Several of them are modified and do not use comedi_unlocked_ioctl(). While functionality of these ioctls essentially copy their original versions, they do not have required sanity check for device's attached status. This, in turn, leads to a possibility of calling select IOCTLs on a device that has not been properly setup, even via COMEDI_DEVCONFIG. Doing so on unconfigured devices means that several crucial steps are missed, for instance, specifying dev->get_valid...

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8723bs: fix out-of-bounds read in rtw_get_ie() parser The Information Element (IE) parser rtw_get_ie() trusted the length byte of each IE without validating that the IE body (len bytes after the 2-byte header) fits inside the remaining frame buffer. A malformed frame can advertise an IE length larger than the available data, causing the parser to increment its pointer beyond the buffer end. This results in out-of-bounds reads or, depending on the pattern, an infinite loop. Fix by validating that (offset + 2 + len) does not exceed the limit before accepting the IE or advancing to the next element. This prevents OOB reads and ensures the parser terminates safely on malformed frames.

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8723bs: fix stack buffer overflow in OnAssocReq IE parsing The Supported Rates IE length from an incoming Association Request frame was used directly as the memcpy() length when copying into a fixed-size 16-byte stack buffer (supportRate). A malicious station can advertise an IE length larger than 16 bytes, causing a stack buffer overflow. Clamp ie_len to the buffer size before copying the Supported Rates IE, and correct the bounds check when merging Extended Supported Rates to prevent a second potential overflow. This prevents kernel stack corruption triggered by malformed association requests.

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8723bs: fix out-of-bounds read in OnBeacon ESR IE parsing The Extended Supported Rates (ESR) IE handling in OnBeacon accessed *(p + 1 + ielen) and *(p + 2 + ielen) without verifying that these offsets lie within the received frame buffer. A malformed beacon with an ESR IE positioned at the end of the buffer could cause an out-of-bounds read, potentially triggering a kernel panic. Add a boundary check to ensure that the ESR IE body and the subsequent bytes are within the limits of the frame before attempting to access them. This prevents OOB reads caused by malformed beacon frames.

In the Linux kernel, the following vulnerability has been resolved: mm: don't spin in add_stack_record when gfp flags don't allow syzbot was able to find the following path: add_stack_record_to_list mm/page_owner.c:182 [inline] inc_stack_record_count mm/page_owner.c:214 [inline] __set_page_owner+0x2c3/0x4a0 mm/page_owner.c:333 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 alloc_pages_nolock_noprof+0x94/0x120 mm/page_alloc.c:7554 Don't spin in add_stack_record_to_list() when it is called from *_nolock() context.

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix dma_buf object leak in fastrpc_map_lookup In fastrpc_map_lookup, dma_buf_get is called to obtain a reference to the dma_buf for comparison purposes. However, this reference is never released when the function returns, leading to a dma_buf memory leak. Fix this by adding dma_buf_put before returning from the function, ensuring that the temporarily acquired reference is properly released regardless of whether a matching map is found. Rule: add

In the Linux kernel, the following vulnerability has been resolved: erofs: avoid infinite loops due to corrupted subpage compact indexes Robert reported an infinite loop observed by two crafted images. The root cause is that `clusterofs` can be larger than `lclustersize` for !NONHEAD `lclusters` in corrupted subpage compact indexes, e.g.: blocksize = lclustersize = 512 lcn = 6 clusterofs = 515 Move the corresponding check for full compress indexes to `z_erofs_load_lcluster_from_disk()` to also cover subpage compact compress indexes. It also fixes the position of `m->type >= Z_EROFS_LCLUSTER_TYPE_MAX` check, since it should be placed right after `z_erofs_load_{compact,full}_lcluster()`.

In the Linux kernel, the following vulnerability has been resolved: hung_task: fix warnings caused by unaligned lock pointers The blocker tracking mechanism assumes that lock pointers are at least 4-byte aligned to use their lower bits for type encoding. However, as reported by Eero Tamminen, some architectures like m68k only guarantee 2-byte alignment of 32-bit values. This breaks the assumption and causes two related WARN_ON_ONCE checks to trigger. To fix this, the runtime checks are adjusted to silently ignore any lock that is not 4-byte aligned, effectively disabling the feature in such cases and avoiding the related warnings. Thanks to Geert Uytterhoeven for bisecting!

In the Linux kernel, the following vulnerability has been resolved: most: usb: hdm_probe: Fix calling put_device() before device initialization The early error path in hdm_probe() can jump to err_free_mdev before &mdev->dev has been initialized with device_initialize(). Calling put_device(&mdev->dev) there triggers a device core WARN and ends up invoking kref_put(&kobj->kref, kobject_release) on an uninitialized kobject. In this path the private struct was only kmalloc'ed and the intended release is effectively kfree(mdev) anyway, so free it directly instead of calling put_device() on an uninitialized device. This removes the WARNING and fixes the pre-initialization error path.

In the Linux kernel, the following vulnerability has been resolved: vmw_balloon: indicate success when effectively deflating during migration When migrating a balloon page, we first deflate the old page to then inflate the new page. However, if inflating the new page succeeded, we effectively deflated the old page, reducing the balloon size. In that case, the migration actually worked: similar to migrating+ immediately deflating the new page. The old page will be freed back to the buddy. Right now, the core will leave the page be marked as isolated (as we returned an error). When later trying to putback that page, we will run into the WARN_ON_ONCE() in balloon_page_putback(). That handling was changed in commit 3544c4faccb8 ("mm/balloon_compaction: stop using __ClearPageMovable()"); before that change, we would have tolerated that way of handling it. To fix it, let's just return 0 in that case, making the core effectively just clear the "isolated" flag + freeing it back to the bud...

In the Linux kernel, the following vulnerability has been resolved: posix-timers: Plug potential memory leak in do_timer_create() When posix timer creation is set to allocate a given timer ID and the access to the user space value faults, the function terminates without freeing the already allocated posix timer structure. Move the allocation after the user space access to cure that. [ tglx: Massaged change log ]

In the Linux kernel, the following vulnerability has been resolved: ksmbd: close accepted socket when per-IP limit rejects connection When the per-IP connection limit is exceeded in ksmbd_kthread_fn(), the code sets ret = -EAGAIN and continues the accept loop without closing the just-accepted socket. That leaks one socket per rejected attempt from a single IP and enables a trivial remote DoS. Release client_sk before continuing. This bug was found with ZeroPath.

In the Linux kernel, the following vulnerability has been resolved: net: netpoll: fix incorrect refcount handling causing incorrect cleanup commit efa95b01da18 ("netpoll: fix use after free") incorrectly ignored the refcount and prematurely set dev->npinfo to NULL during netpoll cleanup, leading to improper behavior and memory leaks. Scenario causing lack of proper cleanup: 1) A netpoll is associated with a NIC (e.g., eth0) and netdev->npinfo is allocated, and refcnt = 1 - Keep in mind that npinfo is shared among all netpoll instances. In this case, there is just one. 2) Another netpoll is also associated with the same NIC and npinfo->refcnt += 1. - Now dev->npinfo->refcnt = 2; - There is just one npinfo associated to the netdev. 3) When the first netpolls goes to clean up: - The first cleanup succeeds and clears np->dev->npinfo, ignoring refcnt. - It basically calls `RCU_INIT_POINTER(np->dev->npinfo, NULL);` - Set dev->npinfo = NULL, without proper cleanup - No ->ndo_netpoll_cleanu...