linux-azure-4.15 vulnerabilities · Page 189

can: bcm: add locking for bcm_op runtime updates

In the Linux kernel, the following vulnerability has been resolved: can: bcm: add locking for bcm_op runtime updates The CAN broadcast manager (CAN BCM) can send a sequence of CAN frames via hrtimer. The content and also the length of the sequence can be changed resp reduced at runtime where the 'currframe' counter is then set to zero. Although this appeared to be a safe operation the updates of 'currframe' can be triggered from user space and hrtimer context in bcm_can_tx(). Anderson Nascimento created a proof of concept that triggered a KASAN slab-out-of-bounds read access which can be prevented with a spin_lock_bh. At the rework of bcm

sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue()

In the Linux kernel, the following vulnerability has been resolved: sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue() When enqueuing the first packet to an HFSC class, hfsc_enqueue() calls the child qdisc's peek() operation before incrementing sch->q.qlen and sch->qstats.backlog. If the child qdisc uses qdisc_peek_dequeued(), this may trigger an immediate dequeue and potential packet drop. In such cases, qdisc_tree_reduce_backlog() is called, but the HFSC qdisc's qlen and backlog have not yet been updated, leading to inconsistent queue accounting. This can leave an empty HFSC class in the active list, causing further conse

• Update to 4.15.0-1190.205

openvswitch: Fix unsafe attribute parsing in output_userspace()

In the Linux kernel, the following vulnerability has been resolved: openvswitch: Fix unsafe attribute parsing in output_userspace() This patch replaces the manual Netlink attribute iteration in output_userspace() with nla_for_each_nested(), which ensures that only well-formed attributes are processed.

module: ensure that kobject_put() is safe for module type kobjects

In the Linux kernel, the following vulnerability has been resolved: module: ensure that kobject_put() is safe for module type kobjects In 'lookup_or_create_module_kobject()', an internal kobject is created using 'module_ktype'. So call to 'kobject_put()' on error handling path causes an attempt to use an uninitialized completion pointer in 'module_kobject_release()'. In this scenario, we just want to release kobject without an extra synchronization required for a regular module unloading process, so adding an extra check whether 'complete()' is actually required makes 'kobject_put()' safe.

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 h

• Update to 4.15.0-1197.212

net_sched: Flush gso_skb list too during ->change()

In the Linux kernel, the following vulnerability has been resolved: net_sched: Flush gso_skb list too during ->change() Previously, when reducing a qdisc's limit via the ->change() operation, only the main skb queue was trimmed, potentially leaving packets in the gso_skb list. This could result in NULL pointer dereference when we only check sch->limit against sch->q.qlen. This patch introduces a new helper, qdisc_dequeue_internal(), which ensures both the gso_skb list and the main queue are properly flushed when trimming excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie) are updated to use this helper in their ->ch

CVE-2025-27558

IEEE P802.11-REVme D1.1 through D7.0 allows FragAttacks against mesh networks. In mesh networks using Wi-Fi Protected Access (WPA, WPA2, or WPA3) or Wired Equivalent Privacy (WEP), an adversary can exploit this vulnerability to inject arbitrary frames towards devices that support receiving non-SSP A-MSDU frames. NOTE: this issue exists because of an incorrect fix for CVE-2020-24588. P802.11-REVme, as of early 2025, is a planned release of the 802.11 standard.

• Update to 4.15.0-1205.220

parisc: Fix double SIGFPE crash

In the Linux kernel, the following vulnerability has been resolved: parisc: Fix double SIGFPE crash Camm noticed that on parisc a SIGFPE exception will crash an application with a second SIGFPE in the signal handler. Dave analyzed it, and it happens because glibc uses a double-word floating-point store to atomically update function descriptors. As a result of lazy binding, we hit a floating-point store in fpe_func almost immediately. When the T bit is set, an assist exception trap occurs when when the co-processor encounters *any* floating-point instruction except for a double store of register %fr0. The latter cancels all pending traps.

wifi: brcm80211: fmac: Add error handling for brcmf_usb_dl_writeimage()

In the Linux kernel, the following vulnerability has been resolved: wifi: brcm80211: fmac: Add error handling for brcmf_usb_dl_writeimage() The function brcmf_usb_dl_writeimage() calls the function brcmf_usb_dl_cmd() but dose not check its return value. The 'state.state' and the 'state.bytes' are uninitialized if the function brcmf_usb_dl_cmd() fails. It is dangerous to use uninitialized variables in the conditions. Add error handling for brcmf_usb_dl_cmd() to jump to error handling path if the brcmf_usb_dl_cmd() fails and the 'state.state' and the 'state.bytes' are uninitialized. Improve the error message to report more detailed error in

UBUNTU-CVE-2025-37976

Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.

net: phy: leds: fix memory leak

In the Linux kernel, the following vulnerability has been resolved: net: phy: leds: fix memory leak A network restart test on a router led to an out-of-memory condition, which was traced to a memory leak in the PHY LED trigger code. The root cause is misuse of the devm API. The registration function (phy_led_triggers_register) is called from phy_attach_direct, not phy_probe, and the unregister function (phy_led_triggers_unregister) is called from phy_detach, not phy_remove. This means the register and unregister functions can be called multiple times for the same PHY device, but devm-allocated memory is not freed until the driver is unboun

qibfs: fix _another_ leak

In the Linux kernel, the following vulnerability has been resolved: qibfs: fix _another_ leak failure to allocate inode => leaked dentry... this one had been there since the initial merge; to be fair, if we are that far OOM, the odds of failing at that particular allocation are low...

wifi: wl1251: fix memory leak in wl1251_tx_work

In the Linux kernel, the following vulnerability has been resolved: wifi: wl1251: fix memory leak in wl1251_tx_work The skb dequeued from tx_queue is lost when wl1251_ps_elp_wakeup fails with a -ETIMEDOUT error. Fix that by queueing the skb back to tx_queue.

block: fix resource leak in blk_register_queue() error path

In the Linux kernel, the following vulnerability has been resolved: block: fix resource leak in blk_register_queue() error path When registering a queue fails after blk_mq_sysfs_register() is successful but the function later encounters an error, we need to clean up the blk_mq_sysfs resources. Add the missing blk_mq_sysfs_unregister() call in the error path to properly clean up these resources and prevent a memory leak.

iio: imu: st_lsm6dsx: fix possible lockup in st_lsm6dsx_read_fifo

In the Linux kernel, the following vulnerability has been resolved: iio: imu: st_lsm6dsx: fix possible lockup in st_lsm6dsx_read_fifo Prevent st_lsm6dsx_read_fifo from falling in an infinite loop in case pattern_len is equal to zero and the device FIFO is not empty.

iio: light: opt3001: fix deadlock due to concurrent flag access

In the Linux kernel, the following vulnerability has been resolved: iio: light: opt3001: fix deadlock due to concurrent flag access The threaded IRQ function in this driver is reading the flag twice: once to lock a mutex and once to unlock it. Even though the code setting the flag is designed to prevent it, there are subtle cases where the flag could be true at the mutex_lock stage and false at the mutex_unlock stage. This results in the mutex not being unlocked, resulting in a deadlock. Fix it by making the opt3001_irq() code generally more robust, reading the flag into a variable and using the variable value at both stages.

arm64: bpf: Only mitigate cBPF programs loaded by unprivileged users

In the Linux kernel, the following vulnerability has been resolved: arm64: bpf: Only mitigate cBPF programs loaded by unprivileged users Support for eBPF programs loaded by unprivileged users is typically disabled. This means only cBPF programs need to be mitigated for BHB. In addition, only mitigate cBPF programs that were loaded by an unprivileged user. Privileged users can also load the same program via eBPF, making the mitigation pointless.

ipvs: fix uninit-value for saddr in do_output_route4

In the Linux kernel, the following vulnerability has been resolved: ipvs: fix uninit-value for saddr in do_output_route4 syzbot reports for uninit-value for the saddr argument [1]. commit 4754957f04f5 ("ipvs: do not use random local source address for tunnels") already implies that the input value of saddr should be ignored but the code is still reading it which can prevent to connect the route. Fix it by changing the argument to ret_saddr. [1] BUG: KMSAN: uninit-value in do_output_route4+0x42c/0x4d0 net/netfilter/ipvs/ip_vs_xmit.c:147 do_output_route4+0x42c/0x4d0 net/netfilter/ipvs/ip_vs_xmit.c:147 __ip_vs_get_out_rt+0x403/0x21d0 net/ne

mm/huge_memory: fix dereferencing invalid pmd migration entry

In the Linux kernel, the following vulnerability has been resolved: mm/huge_memory: fix dereferencing invalid pmd migration entry When migrating a THP, concurrent access to the PMD migration entry during a deferred split scan can lead to an invalid address access, as illustrated below. To prevent this invalid access, it is necessary to check the PMD migration entry and return early. In this context, there is no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the equality of the target folio. Since the PMD migration entry is locked, it cannot be served as the target. Mailing list discussion and explanation from Hugh Dic

• Update to 4.15.0-1195.210

xenbus: Use kref to track req lifetime

In the Linux kernel, the following vulnerability has been resolved: xenbus: Use kref to track req lifetime Marek reported seeing a NULL pointer fault in the xenbus_thread callstack: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: e030:__wake_up_common+0x4c/0x180 Call Trace: <TASK> __wake_up_common_lock+0x82/0xd0 process_msg+0x18e/0x2f0 xenbus_thread+0x165/0x1c0 process_msg+0x18e is req->cb(req). req->cb is set to xs_wake_up(), a thin wrapper around wake_up(), or xenbus_dev_queue_reply(). It seems like it was xs_wake_up() in this case. It seems like req may have woken up the xs_wait_for_reply(), which kfree()ed t