Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix possible infinite loop and oob read in symlink_data() On 32-bit architectures, the infinite loop is as follows: len = p->ErrorDataLength == 0xfffffff8 u8 *next = p->ErrorContextData + len next == p On 32-bit architectures, the out-of-bounds read is as follows: len = p->ErrorDataLength == 0xfffffff0 u8 *next = p->ErrorContextData + len next == (u8 *)p - 8Show less

In the Linux kernel, the following vulnerability has been resolved: drm: Replace old pointer to new idr Commit 5e28b7b94408 introduced a logical error by failing to replace the newly generated IDR pointer to old id's pointer at the correct location within the "change handle" logic; this resulted in the issue reported by syzbot [1]. Specifically, the new IDR object pointer is intended to replace the original id's pointer during the normal execution flow. Additionally, an unnecessary conditional check for the ret exit path has been removed. [1] !RB_EMPTY_ROOT(&prime_fpriv->dmabufs) WARNING: drivers/gpu/drm/drm_prime.c:224 at drm_prime_destroy_file_private+0x48/0x60 drivers/gpu/drm/drm_prime.c:224, CPU#0: syz.0.17/5833 Call Trace: drm_file_free.part.0+0x7e6/0xcc0 drivers/gpu/drm/drm_file.c:269 drm_file_free drivers/gpu/drm/drm_file.c:237 [inline] drm_close_helper.isra.0+0x186/0x200 drivers/gpu/drm/drm_file.c:290 drm_release+0x1ab/0x360 drivers/gpu/drm/drm_file.c:438Show less

In the Linux kernel, the following vulnerability has been resolved: drm/ttm: Fix ttm_bo_swapout() infinite LRU walk on swapout failure When ttm_tt_swapout() fails, the current code calls ttm_resource_add_bulk_move() followed by ttm_resource_move_to_lru_tail() to restore the resource's bulk_move membership. However, ttm_resource_move_to_lru_tail() places the resource at the tail of the LRU list which, relative to the walk cursor's hitch node (placed immediately after the resource when it was yielded), puts the resource *in front of the* the hitch. The next list_for_each_entry_continue() from the hitch finds the same resource again, causing an infinite loop. Fix by deferring del_bulk_move to the success path only. On the success path, TTM_TT_FLAG_SWAPPED has just been set by ttm_tt_swapout() but the resource is still tracked in the bulk_move range, so ttm_resource_del_bulk_move()'s !ttm_resource_unevictable() guard would incorrectly skip the removal. Introduce ttm_resource_del_bulk_move_unevictable() which bypasses that guard.Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Bound MIDI 2.0 endpoint descriptor scans The USB MIDI 2.0 endpoint parser has the same descriptor walking pattern as the legacy MIDI parser. It validates bLength against bNumGrpTrmBlock before reading baAssoGrpTrmBlkID[], but not against the remaining bytes in the endpoint-extra scan. A malformed device can therefore make later baAssoGrpTrmBlkID[] reads consume bytes past the walked descriptor. Reject zero-length and overlong descriptors while walking endpoint extras.Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Bound MIDI endpoint descriptor scans snd_usbmidi_get_ms_info() validates the internal MIDIStreaming endpoint descriptor size before using baAssocJackID[], but the descriptor walker can still return a class-specific endpoint descriptor whose bLength exceeds the remaining bytes in the endpoint-extra scan. That leaves later flexible-array reads bounded by bLength, but not by the remaining bytes in the endpoint-extra scan. Stop walking when bLength is zero or extends past the remaining endpoint-extra scan.Show less

In the Linux kernel, the following vulnerability has been resolved: ceph: fix a buffer leak in __ceph_setxattr() The old_blob in __ceph_setxattr() can store ci->i_xattrs.prealloc_blob value during the retry. However, it is never called the ceph_buffer_put() for the old_blob object. This patch fixes the issue of the buffer leak.Show less

In the Linux kernel, the following vulnerability has been resolved: ceph: fix BUG_ON in __ceph_build_xattrs_blob() due to stale blob size The generic/642 test-case can reproduce the kernel crash: [40243.605254] ------------[ cut here ]------------ [40243.605956] kernel BUG at fs/ceph/xattr.c:918! [40243.607142] Oops: invalid opcode: 0000 [#1] SMP PTI [40243.608067] CPU: 7 UID: 0 PID: 498762 Comm: kworker/7:1 Not tainted 7.0.0-rc7+ #3 PREEMPT(full) [40243.609700] Hardware name: QEMU Ubuntu 25.10 PC v2 (i440FX + PIIX, + 10.1 machine, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [40243.611820] Workqueue: ceph-msgr ceph_con_workfn [40243.612715] RIP: 0010:__ceph_build_xattrs_blob+0x1b8/0x1e0 [40243.613731] Code: 0f 84 82 fe ff ff e9 cf 8e 56 ff 48 8d 65 e8 31 c0 5b 41 5c 41 5d 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 c3 cc cc cc cc <0f> 0b 4c 8b 62 08 41 8b 85 24 07 00 00 49 83 c4 04 41 89 44 24 fc [40243.616888] RSP: 0018:ffffcc80c4d4b688 EFLAGS: 00010287 [40243.617773] RAX: 0000000000010026 RBX: 0000000000000001 RCX: 0000000000000000 [40243.618928] RDX: ffff8a773798dee0 RSI: 0000000000000000 RDI: 0000000000000000 [40243.620158] RBP: ffffcc80c4d4b6a0 R08: 0000000000000000 R09: 0000000000000000 [40243.621573] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a75f3b58000 [40243.622907] R13: ffff8a75f3b58000 R14: 0000000000000080 R15: 000000000000bffd [40243.624054] FS: 0000000000000000(0000) GS:ffff8a787d1b4000(0000) knlGS:0000000000000000 [40243.625331] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [40243.626269] CR2: 000072f390b623c0 CR3: 000000011c02a003 CR4: 0000000000372ef0 [40243.627408] Call Trace: [40243.627839] <TASK> [40243.628188] __prep_cap+0x3fd/0x4a0 [40243.628789] ? do_raw_spin_unlock+0x4e/0xe0 [40243.629474] ceph_check_caps+0x46a/0xc80 [40243.630094] ? __lock_acquire+0x4a2/0x2650 [40243.630773] ? find_held_lock+0x31/0x90 [40243.631347] ? handle_cap_grant+0x79f/0x1060 [40243.632068] ? lock_release+0xd9/0x300 [40243.632696] ? __mutex_unlock_slowpath+0x3e/0x340 [40243.633429] ? lock_release+0xd9/0x300 [40243.634052] handle_cap_grant+0xcf6/0x1060 [40243.634745] ceph_handle_caps+0x122b/0x2110 [40243.635415] mds_dispatch+0x5bd/0x2160 [40243.636034] ? ceph_con_process_message+0x65/0x190 [40243.636828] ? lock_release+0xd9/0x300 [40243.637431] ceph_con_process_message+0x7a/0x190 [40243.638184] ? kfree+0x311/0x4f0 [40243.638749] ? kfree+0x311/0x4f0 [40243.639268] process_message+0x16/0x1a0 [40243.639915] ? sg_free_table+0x39/0x90 [40243.640572] ceph_con_v2_try_read+0xf58/0x2120 [40243.641255] ? lock_acquire+0xc8/0x300 [40243.641863] ceph_con_workfn+0x151/0x820 [40243.642493] process_one_work+0x22f/0x630 [40243.643093] ? process_one_work+0x254/0x630 [40243.643770] worker_thread+0x1e2/0x400 [40243.644332] ? __pfx_worker_thread+0x10/0x10 [40243.645020] kthread+0x109/0x140 [40243.645560] ? __pfx_kthread+0x10/0x10 [40243.646125] ret_from_fork+0x3f8/0x480 [40243.646752] ? __pfx_kthread+0x10/0x10 [40243.647316] ? __pfx_kthread+0x10/0x10 [40243.647919] ret_from_fork_asm+0x1a/0x30 [40243.648556] </TASK> [40243.648902] Modules linked in: overlay hctr2 libpolyval chacha libchacha adiantum libnh libpoly1305 essiv intel_rapl_msr intel_rapl_common intel_uncore_frequency_common skx_edac_common nfit kvm_intel kvm irqbypass joydev ghash_clmulni_intel aesni_intel rapl input_leds mac_hid psmouse vga16fb serio_raw vgastate floppy i2c_piix4 pata_acpi bochs qemu_fw_cfg i2c_smbus sch_fq_codel rbd dm_crypt msr parport_pc ppdev lp parport efi_pstore [40243.654766] ---[ end trace 0000000000000000 ]--- Commit d93231a6bc8a ("ceph: prevent a client from exceeding the MDS maximum xattr size") moved the required_blob_size computation to before the __build_xattrs() call, introducing a race. __build_xattrs() releases and reacquires i_ceph_lock during execution. In that window, handle_cap_grant() may update i_xattrs.blob with a newer MDS-provided blob and bump i_xattrs.version. When __bui ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: ceph: put folios not suitable for writeback The batch holds references to the folios (see `filemap_get_folios`, `folio_batch_release`), so we need to `folio_put` the folios we remove. Tested on v6.18.Show less

In the Linux kernel, the following vulnerability has been resolved: virt: sev-guest: Do not use host-controlled page order in cleanup path When issuing an extended guest request (SVM_VMGEXIT_EXT_GUEST_REQUEST), get_ext_report() allocates a buffer to retrieve a certificate blob from the host, keeping track of its size in report_req->certs_len. However, the host may return SNP_GUEST_VMM_ERR_INVALID_LEN, indicating an invalid buffer size, as well as the expected length of such buffer. get_ext_report() subsequently updates report_req->certs_len with the host-controlled value, and cleans up the buffer by computing a page order from such value. This is incorrect, as the host-provided length may not match the page order of the original allocation, potentially resulting in corruption in the page allocator. Fix this by using alloc_pages_exact() instead, and reusing @npages to compute the size passed to free_pages_exact(). For consistency, also use @npages to compute the size when allocating the pages, even though this last change has no functional effect.Show less

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in osdmap_decode() When decoding osd_state and osd_weight from an incoming osdmap in osdmap_decode(), both are decoded for each osd, i.e., map->max_osd times. The ceph_decode_need() check only accounts for sizeof(*map->osd_weight) once. This can potentially result in an out-of-bounds memory access if the incoming message is corrupted such that the max_osd value exceeds the actual content of the osdmap message. This patch fixes the issue by changing the corresponding part in the ceph_decode_need() check to account for map->max_osd*sizeof(*map->osd_weight).Show less

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential null-ptr-deref in decode_choose_args() A message of type CEPH_MSG_OSD_MAP contains an OSD map that itself contains a CRUSH map. When decoding this CRUSH map in crush_decode(), an array of max_buckets CRUSH buckets is decoded, where some indices may not refer to actual buckets and are therefore set to NULL. The received CRUSH map may optionally contain choose_args that get decoded in decode_choose_args(). When decoding a crush_choose_arg_map, a series of choose_args for different buckets is decoded, with the bucket_index being read from the incoming message. It is only checked that the bucket index does not exceed max_buckets, but not that it doesn't point to an index with a NULL bucket. If a (potentially corrupted) message contains a crush_choose_arg_map including such a bucket_index, a null pointer dereference may occur in the subsequent processing when attempting to access the bucket with the given index. This patch fixes the issue by extending the affected check. Now, it is only attempted to access the bucket if it is not NULL.Show less

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in __ceph_x_decrypt() In __ceph_x_decrypt(), a part of the buffer p is interpreted as a ceph_x_encrypt_header, and the magic field of this struct is accessed. This happens without any guarantee that the buffer is large enough to hold this struct. The function parameter ciphertext_len represents the length of the ciphertext to decrypt and is guaranteed to be at most the remaining size of the allocated buffer p. However, this value is not necessarily greater than sizeof(ceph_x_encrypt_header). E.g., a message frame of type FRAME_TAG_AUTH_REPLY_MORE, that is just as long to hold the ciphertext at its end with a ciphertext_len of 8 or less, can trigger an out-of-bounds memory access when accessing hdr->magic. This patch fixes the issue by adding a check to ensure that the decrypted plaintext in the buffer is large enough to represent at least the ceph_x_encrypt_header.Show less

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in crush_decode() A message of type CEPH_MSG_OSD_MAP containing a crush map with at least one bucket has two fields holding the bucket algorithm. If the values in these two fields differ, an out-of-bounds access can occur. This is the case because the first algorithm field (alg) is used to allocate the correct amount of memory for a bucket of this type, while the second algorithm field inside the bucket (b->alg) is used in the subsequent processing. This patch fixes the issue by adding a check that compares alg and b->alg and aborts the processing in case they differ. Furthermore, b->alg is set to 0 in this case, because the destruction of the crush map also uses this field to determine the bucket type, which can again result in an out-of-bounds access when trying to free the memory pointed to by the fields of the bucket. To correctly free the memory allocated for the bucket in such a case, the corresponding call to kfree is moved from the algorithm-specific crush_destroy_bucket functions to the generic crush_destroy_bucket().Show less

In the Linux kernel, the following vulnerability has been resolved: libceph: handle rbtree insertion error in decode_choose_args() A message of type CEPH_MSG_OSD_MAP contains an OSD map that itself contains a CRUSH map. The received CRUSH map may optionally contain choose_args that get decoded in decode_choose_args(). In this function, num_choose_arg_maps is read from the message, and a corresponding number of crush_choose_arg_maps gets decoded afterwards. Each crush_choose_arg_map has a choose_args_index, which serves as the key when inserting it into the choose_args rbtree of the decoded crush_map. If a (potentially corrupted) message contains two crush_choose_arg_maps with the same index, the assertion in insert_choose_arg_map() triggers a kernel BUG when trying to insert the second crush_choose_arg_map. This patch fixes the issue by switching to the non-asserting rbtree insertion function and rejecting the message if the insertion fails. [ idryomov: changelog ]Show less

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix oops due to out of scope access Below oops triggers when kill QEMU process: Oops: general protection fault, probably for non-canonical address 0x7fffffff844eaaa7: 0000 [#1] SMP NOPTI Call Trace: <TASK> do_raw_spin_lock+0xaa/0xc0 _raw_spin_lock_irqsave+0x21/0x40 domain_remove_dev_pasid+0x52/0x160 intel_nested_set_dev_pasid+0x1b9/0x1e0 __iommu_set_group_pasid+0x56/0x120 pci_dev_reset_iommu_done+0xe3/0x180 pcie_flr+0x65/0x160 __pci_reset_function_locked+0x5b/0x120 vfio_pci_core_close_device+0x63/0xe0 [vfio_pci_core] vfio_df_close+0x4f/0xa0 vfio_df_unbind_iommufd+0x2d/0x60 vfio_device_fops_release+0x3e/0x40 __fput+0xe5/0x2c0 task_work_run+0x58/0xa0 do_exit+0x2c8/0x600 do_group_exit+0x2f/0xa0 get_signal+0x863/0x8c0 arch_do_signal_or_restart+0x24/0x100 exit_to_user_mode_loop+0x87/0x380 do_syscall_64+0x2ff/0x11e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The global static blocked domain is a dummy domain without corresponding dmar_domain structure, accessing beyond iommu_domain structure triggers oops easily. Fix it by return early in domain_remove_dev_pasid() like identity domain.Show less

In the Linux kernel, the following vulnerability has been resolved: iommu: Fix WARN_ON in __iommu_group_set_domain_nofail() due to reset In __iommu_group_set_domain_internal(), concurrent domain attachments are rejected when any device in the group is recovering. This is necessary to fence concurrent attachments to a multi-device group where devices might share the same RID due to PCI DMA alias quirks, but triggers the WARN_ON in __iommu_group_set_domain_nofail(). Other IOMMU_SET_DOMAIN_MUST_SUCCEED callers in detach/teardown paths, such as __iommu_group_set_core_domain and __iommu_release_dma_ownership, should not be rejected, as the domain would be freed anyway in these nofail paths while group->domain is still pointing to it. So pci_dev_reset_iommu_done() could trigger a UAF when re-attaching group->domain. Honor the IOMMU_SET_DOMAIN_MUST_SUCCEED flag, allowing the callers through the group->recovery_cnt fence, so as to update the group->domain pointer. Instead add a gdev->blocked check in the device iteration loop, to prevent any concurrent per-device detachment.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/xe/dma-buf: handle empty bo and UAF races There look to be some nasty races here when triggering the invalidate_mappings hook: 1) We do xe_bo_alloc() followed by the attach, before the actual full bo init step in xe_dma_buf_init_obj(). However the bo is visible on the attachments list after the attach. This is bad since exporter driver, say amdgpu, can at any time call back into our invalidate_mappings hook, with an empty/bogus bo, leading to potential bugs/crashes. 2) Similar to 1) but here we get a UAF, when the invalidate_mappings hook is triggered. For example, we get as far as xe_bo_init_locked() but this fails in some way. But here the bo will be freed on error, but we still have it attached from dma-buf pov, so if the invalidate_mappings is now triggered then the bo we access is gone and we trigger UAF and more bugs/crashes. To fix this, move the attach step until after we actually have a fully set up buffer object. Note that the bo is not published to userspace until later, so not sure what the comment "Don't publish the bo until we have a valid attachment", is referring to. We have at least two different customers reporting hitting a NULL ptr deref in evict_flags when importing something from amdgpu, followed by triggering the evict flow. Hit rate is also pretty low, which would hint at some kind of race, so something like 1) or 2) might explain this. v2: - Shuffle the order of the ops slightly (no functional change) - Improve the comment to better explain the ordering (Matt B) (cherry picked from commit af1f2ad0c59fe4e2f924c526f66e968289d77971)Show less

In the Linux kernel, the following vulnerability has been resolved: drm/xe/dma-buf: fix UAF with retry loop Retry doesn't work here, since bo will be freed on error, leading to UAF. However, now that we do the alloc & init before the attach, we can now combine this as one unit and have the init do the alloc for us. This should make the retry safe. Reported by Sashiko. v2: Fix up the error unwind (CI) (cherry picked from commit 479669418253e0f27f8cf5db01a731352ea592e7)Show less

In the Linux kernel, the following vulnerability has been resolved: drm/ttm: Fix ttm_bo_shrink() infinite LRU walk on backup failure Apply the same fix as b2ed01e7ad ("drm/ttm: Fix ttm_bo_swapout() infinite LRU walk on swapout failure") to the ttm_bo_shrink() path. Move del_bulk_move from before the backup to after success only, using ttm_resource_del_bulk_move_unevictable() since the resource is now unevictable once fully backed up.Show less

In the Linux kernel, the following vulnerability has been resolved: i2c: dev: prevent integer overflow in I2C_TIMEOUT ioctl While fuzzing with Syzkaller, a persistent `schedule_timeout: wrong timeout value` warning was observed, accompanied by SMBus controller state machine corruption. The I2C_TIMEOUT ioctl accepts a user-provided timeout in multiples of 10 ms. The user argument is checked against INT_MAX, but it is subsequently multiplied by 10 before being passed to msecs_to_jiffies(). A malicious user can pass a large value (e.g., 429496729) that passes the `arg > INT_MAX` check but overflows when multiplied by 10. This results in a truncated 32-bit unsigned value that bypasses the internal `(int)m < 0` check in `msecs_to_jiffies()`. The truncated value is then assigned to `client->adapter->timeout` (a signed 32-bit int), which is reinterpreted as a negative number. When passed to wait_for_completion_timeout(), this negative value undergoes sign extension to a 64-bit unsigned long, triggering the `schedule_timeout` warning and causing premature returns. This leaves the SMBus state machine in an unrecoverable state, constituting a local Denial of Service (DoS). Fix this by bounding the user argument to `INT_MAX / 10`. [wsa: move the comment as well]Show less