LSN-0112-1: Kernel Live Patch Security Notice

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix use-after-free due to delegation race A delegation break could arrive as soon as we've called vfs_setlease. A delegation break runs a callback which immediately (in nfsd4_cb_recall_prepare) adds the delegation to del_recall_lru. If we then exit nfs4_set_delegation without hashing the delegation, it will be freed as soon as the callback is done with it, without ever being removed from del_recall_lru. Symptoms show up later as use-after-free or list corruption warnings, usually in the laundromat thread. I suspect aba2072f4523 'nfsd: grant read delegations to clients holding writes' made this bug easier to hit, but I looked as far back as v3.0 and it looks to me it already had the same problem. So I'm not sure where the bug was introduced; it may have been there from the beginning.)(CVE-2021-47506) Jann Horn discovered that the watch_queue event notification subsystem in the Linux kernel contained an out-of-bounds write vulnerability. A local attacker could use this to cause a denial of service (system crash) or escalate their privileges.)(CVE-2022-0995) In the Linux kernel, the following vulnerability has been resolved: net: atlantic: eliminate double free in error handling logic Driver has a logic leak in ring data allocation/free, where aq_ring_free could be called multiple times on same ring, if system is under stress and got memory allocation error. Ring pointer was used as an indicator of failure, but this is not correct since only ring data is allocated/deallocated. Ring itself is an array member. Changing ring allocation functions to return error code directly. This simplifies error handling and eliminates aq_ring_free on higher layer.)(CVE-2023-52664) In the Linux kernel, the following vulnerability has been resolved: ceph: prevent use-after-free in encode_cap_msg() In fs/ceph/caps.c, in encode_cap_msg(), 'use after free' error was caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This implies before the refcount could be increment here, it was freed. In same file, in 'handle_cap_grant()' refcount is decremented by this line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race occurred and resource was freed by the latter line before the former line could increment it. encode_cap_msg() is called by __send_cap() and __send_cap() is called by ceph_check_caps() after calling __prep_cap(). __prep_cap() is where arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where the refcount must be increased to prevent 'use after free' error.)(CVE-2024-26689) In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential UAF in smb2_is_valid_lease_break() Skip sessions that are being teared down (status == SES_EXITING) to avoid UAF.)(CVE-2024-35864) In the Linux kernel, the following vulnerability has been resolved: HID: core: zero-initialize the report buffer Since the report buffer is used by all kinds of drivers in various ways, let's zero- initialize it during allocation to make sure that it can't be ever used to leak kernel memory via specially-crafted report.)(CVE-2024-50302) In the Linux kernel, the following vulnerability has been resolved: media: dvbdev: prevent the risk of out of memory access The dvbdev contains a static variable used to store dvb minors. The behavior of it depends if CONFIG_DVB_DYNAMIC_MINORS is set or not. When not set, dvb_register_device() won't check for boundaries, as it will rely that a previous call to dvb_register_adapter() would already be enforcing it. On a similar way, dvb_device_open() uses the assumption that the register functions already did the needed checks. This can be fragile if some device ends using different calls. This also generate warnings on static check analysers like Coverity. So, add explicit guards to prevent potential risk of OOM issues.)(CVE-2024-53063) In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Fix out of bounds reads when finding clock sources The current USB-audio driver code doesn't check bLength of each descriptor at traversing for clock descriptors. That is, when a device provides a bogus descriptor with a shorter bLength, the driver might hit out-of-bounds reads. For addressing it, this patch adds sanity checks to the validator functions for the clock descriptor traversal. When the descriptor length is shorter than expected, it's skipped in the loop. For the clock source and clock multiplier descriptors, we can just check bLength against the sizeof() of each descriptor type. OTOH, the clock selector descriptor of UAC2 and UAC3 has an array of bNrInPins elements and two more fields at its tail, hence those have to be checked in addition to the sizeof() check.)(CVE-2024-53150) In the Linux kernel, the following vulnerability has been resolved: sunrpc: fix one UAF issue caused by sunrpc kernel tcp socket BUG: KASAN: slab-use-after-free in tcp_write_timer_handler+0x156/0x3e0 (CVE-2024-53168) In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Fix potential out-of-bound accesses for Extigy and Mbox devices A bogus device can provide a bNumConfigurations value that exceeds the initial value used in usb_get_configuration for allocating dev->config. This can lead to out-of-bounds accesses later, e.g. in usb_destroy_configuration.)(CVE-2024-53197) In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix usage slab after free [ +0.000021] BUG: KASAN: slab-use-after-free in drm_sched_entity_flush+0x6cb/0x7a0 (CVE-2024-56551) In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: Fix oops due to NULL pointer dereference in brcmf_sdiod_sglist_rw() This patch fixes a NULL pointer dereference bug in brcmfmac that occurs when a high 'sd_sgentry_align' value applies (e.g. 512) and a lot of queued SKBs are sent from the pkt queue. The problem is the number of entries in the pre-allocated sgtable, it is nents = max(rxglom_size, txglom_size) + max(rxglom_size, txglom_size) >> 4 + 1. Given the default [rt]xglom_size=32 it's actually 35 which is too small. Worst case, the pkt queue can end up with 64 SKBs. This occurs when a new SKB is added for each original SKB if tailroom isn't enough to hold tail_pad. At least one sg entry is needed for each SKB. So, eventually the 'skb_queue_walk loop' in brcmf_sdiod_sglist_rw may run out of sg entries. This makes sg_next return NULL and this causes the oops. The patch sets nents to max(rxglom_size, txglom_size) * 2 to be able handle the worst- case. Btw. this requires only 64-35=29 * 16 (or 20 if CONFIG_NEED_SG_DMA_LENGTH) = 464 additional bytes of memory.)(CVE-2024-56593) In the Linux kernel, the following vulnerability has been resolved: jfs: add a check to prevent array-index-out-of-bounds in dbAdjTree When the value of lp is 0 at the beginning of the for loop, it will become negative in the next assignment and we should bail out.)(CVE-2024-56595) In the Linux kernel, the following vulnerability has been resolved: jfs: array-index-out-of-bounds fix in dtReadFirst The value of stbl can be sometimes out of bounds due to a bad filesystem. Added a check with appopriate return of error code in that case.)(CVE-2024-56598) In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btmtk: avoid UAF in btmtk_process_coredump hci_devcd_append may lead to the release of the skb, so it cannot be accessed once it is called. (CVE-2024-56653) In the Linux kernel, the following vulnerability has been resolved: drm/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req() While receiving an MST up request message from one thread in drm_dp_mst_handle_up_req(), the MST topology could be removed from another thread via drm_dp_mst_topology_mgr_set_mst(false), freeing mst_primary and setting drm_dp_mst_topology_mgr::mst_primary to NULL. This could lead to a NULL deref/use-after-free of mst_primary in drm_dp_mst_handle_up_req(). Avoid the above by holding a reference for mst_primary in drm_dp_mst_handle_up_req() while it's used. v2: Fix kfreeing the request if getting an mst_primary reference fails.)(CVE-2024-57798)