CVSS: -EPSS: 0%CPEs: 8EXPL: 0CVE-2024-26696 – nilfs2: fix hang in nilfs_lookup_dirty_data_buffers()
https://notcve.org/view.php?id=CVE-2024-26696
In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix hang in nilfs_lookup_dirty_data_buffers() Syzbot reported a hang issue in migrate_pages_batch() called by mbind() and nilfs_lookup_dirty_data_buffers() called in the log writer of nilfs2. While migrate_pages_batch() locks a folio and waits for the writeback to complete, the log writer thread that should bring the writeback to completion picks up the folio being written back in nilfs_lookup_dirty_data_buffers() that it calls for subsequent log creation and was trying to lock the folio. Thus causing a deadlock. In the first place, it is unexpected that folios/pages in the middle of writeback will be updated and become dirty. Nilfs2 adds a checksum to verify the validity of the log being written and uses it for recovery at mount, so data changes during writeback are suppressed. Since this is broken, an unclean shutdown could potentially cause recovery to fail. Investigation revealed that the root cause is that the wait for writeback completion in nilfs_page_mkwrite() is conditional, and if the backing device does not require stable writes, data may be modified without waiting. Fix these issues by making nilfs_page_mkwrite() wait for writeback to finish regardless of the stable write requirement of the backing device. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: nilfs2: corrige un bloqueo en nilfs_lookup_dirty_data_buffers() Syzbot informó un problema de bloqueo en migrar_pages_batch() llamado por mbind() y nilfs_lookup_dirty_data_buffers() llamado en el escritor de registros de nilfs2. • https://git.kernel.org/stable/c/1d1d1a767206fbe5d4c69493b7e6d2a8d08cc0a0 https://git.kernel.org/stable/c/228742b2ddfb99dfd71e5a307e6088ab6836272e https://git.kernel.org/stable/c/862ee4422c38be5c249844a684b00d0dbe9d1e46 https://git.kernel.org/stable/c/98a4026b22ff440c7f47056481bcbbe442f607d6 https://git.kernel.org/stable/c/7e9b622bd0748cc104d66535b76d9b3535f9dc0f https://git.kernel.org/stable/c/8494ba2c9ea00a54d5b50e69b22c55a8958bce32 https://git.kernel.org/stable/c/ea5ddbc11613b55e5128c85f57b08f907abd9b28 https://git.kernel.org/stable/c/e38585401d464578d30f5868ff4ca5447 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2024-26691 – KVM: arm64: Fix circular locking dependency
https://notcve.org/view.php?id=CVE-2024-26691
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Fix circular locking dependency The rule inside kvm enforces that the vcpu->mutex is taken *inside* kvm->lock. The rule is violated by the pkvm_create_hyp_vm() which acquires the kvm->lock while already holding the vcpu->mutex lock from kvm_vcpu_ioctl(). Avoid the circular locking dependency altogether by protecting the hyp vm handle with the config_lock, much like we already do for other forms of VM-scoped data. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: KVM: arm64: corrige la dependencia de bloqueo circular La regla dentro de kvm exige que vcpu->mutex se tome *dentro* de kvm->lock. La regla es violada por pkvm_create_hyp_vm() que adquiere el bloqueo kvm->mientras ya mantiene el bloqueo vcpu->mutex de kvm_vcpu_ioctl(). • https://git.kernel.org/stable/c/3d16cebf01127f459dcfeb79ed77bd68b124c228 https://git.kernel.org/stable/c/3ab1c40a1e915e350d9181a4603af393141970cc https://git.kernel.org/stable/c/10c02aad111df02088d1a81792a709f6a7eca6cc •
CVSS: -EPSS: 0%CPEs: 6EXPL: 0CVE-2024-26689 – ceph: prevent use-after-free in encode_cap_msg()
https://notcve.org/view.php?id=CVE-2024-26689
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. • https://git.kernel.org/stable/c/8180d0c27b93a6eb60da1b08ea079e3926328214 https://git.kernel.org/stable/c/70e329b440762390258a6fe8c0de93c9fdd56c77 https://git.kernel.org/stable/c/f3f98d7d84b31828004545e29fd7262b9f444139 https://git.kernel.org/stable/c/ae20db45e482303a20e56f2db667a9d9c54ac7e7 https://git.kernel.org/stable/c/7958c1bf5b03c6f1f58e724dbdec93f8f60b96fc https://git.kernel.org/stable/c/cda4672da1c26835dcbd7aec2bfed954eda9b5ef https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html •
CVSS: -EPSS: 0%CPEs: 7EXPL: 0CVE-2024-26688 – fs,hugetlb: fix NULL pointer dereference in hugetlbs_fill_super
https://notcve.org/view.php?id=CVE-2024-26688
In the Linux kernel, the following vulnerability has been resolved: fs,hugetlb: fix NULL pointer dereference in hugetlbs_fill_super When configuring a hugetlb filesystem via the fsconfig() syscall, there is a possible NULL dereference in hugetlbfs_fill_super() caused by assigning NULL to ctx->hstate in hugetlbfs_parse_param() when the requested pagesize is non valid. E.g: Taking the following steps: fd = fsopen("hugetlbfs", FSOPEN_CLOEXEC); fsconfig(fd, FSCONFIG_SET_STRING, "pagesize", "1024", 0); fsconfig(fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0); Given that the requested "pagesize" is invalid, ctxt->hstate will be replaced with NULL, losing its previous value, and we will print an error: ... ... case Opt_pagesize: ps = memparse(param->string, &rest); ctx->hstate = h; if (!ctx->hstate) { pr_err("Unsupported page size %lu MB\n", ps / SZ_1M); return -EINVAL; } return 0; ... ... This is a problem because later on, we will dereference ctxt->hstate in hugetlbfs_fill_super() ... ... sb->s_blocksize = huge_page_size(ctx->hstate); ... ... Causing below Oops. Fix this by replacing cxt->hstate value only when then pagesize is known to be valid. kernel: hugetlbfs: Unsupported page size 0 MB kernel: BUG: kernel NULL pointer dereference, address: 0000000000000028 kernel: #PF: supervisor read access in kernel mode kernel: #PF: error_code(0x0000) - not-present page kernel: PGD 800000010f66c067 P4D 800000010f66c067 PUD 1b22f8067 PMD 0 kernel: Oops: 0000 [#1] PREEMPT SMP PTI kernel: CPU: 4 PID: 5659 Comm: syscall Tainted: G E 6.8.0-rc2-default+ #22 5a47c3fef76212addcc6eb71344aabc35190ae8f kernel: Hardware name: Intel Corp. GROVEPORT/GROVEPORT, BIOS GVPRCRB1.86B.0016.D04.1705030402 05/03/2017 kernel: RIP: 0010:hugetlbfs_fill_super+0xb4/0x1a0 kernel: Code: 48 8b 3b e8 3e c6 ed ff 48 85 c0 48 89 45 20 0f 84 d6 00 00 00 48 b8 ff ff ff ff ff ff ff 7f 4c 89 e7 49 89 44 24 20 48 8b 03 <8b> 48 28 b8 00 10 00 00 48 d3 e0 49 89 44 24 18 48 8b 03 8b 40 28 kernel: RSP: 0018:ffffbe9960fcbd48 EFLAGS: 00010246 kernel: RAX: 0000000000000000 RBX: ffff9af5272ae780 RCX: 0000000000372004 kernel: RDX: ffffffffffffffff RSI: ffffffffffffffff RDI: ffff9af555e9b000 kernel: RBP: ffff9af52ee66b00 R08: 0000000000000040 R09: 0000000000370004 kernel: R10: ffffbe9960fcbd48 R11: 0000000000000040 R12: ffff9af555e9b000 kernel: R13: ffffffffa66b86c0 R14: ffff9af507d2f400 R15: ffff9af507d2f400 kernel: FS: 00007ffbc0ba4740(0000) GS:ffff9b0bd7000000(0000) knlGS:0000000000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kernel: CR2: 0000000000000028 CR3: 00000001b1ee0000 CR4: 00000000001506f0 kernel: Call Trace: kernel: <TASK> kernel: ? __die_body+0x1a/0x60 kernel: ? page_fault_oops+0x16f/0x4a0 kernel: ? • https://git.kernel.org/stable/c/32021982a324dce93b4ae00c06213bf45fb319c8 https://git.kernel.org/stable/c/1dde8ef4b7a749ae1bc73617c91775631d167557 https://git.kernel.org/stable/c/80d852299987a8037be145a94f41874228f1a773 https://git.kernel.org/stable/c/22850c9950a4e43a67299755d11498f3292d02ff https://git.kernel.org/stable/c/2e2c07104b4904aed1389a59b25799b95a85b5b9 https://git.kernel.org/stable/c/13c5a9fb07105557a1fa9efdb4f23d7ef30b7274 https://git.kernel.org/stable/c/ec78418801ef7b0c22cd6a30145ec480dd48db39 https://git.kernel.org/stable/c/79d72c68c58784a3e1cd2378669d51bfd •
CVSS: -EPSS: 0%CPEs: 7EXPL: 0CVE-2024-26687 – xen/events: close evtchn after mapping cleanup
https://notcve.org/view.php?id=CVE-2024-26687
In the Linux kernel, the following vulnerability has been resolved: xen/events: close evtchn after mapping cleanup shutdown_pirq and startup_pirq are not taking the irq_mapping_update_lock because they can't due to lock inversion. Both are called with the irq_desc->lock being taking. The lock order, however, is first irq_mapping_update_lock and then irq_desc->lock. This opens multiple races: - shutdown_pirq can be interrupted by a function that allocates an event channel: CPU0 CPU1 shutdown_pirq { xen_evtchn_close(e) __startup_pirq { EVTCHNOP_bind_pirq -> returns just freed evtchn e set_evtchn_to_irq(e, irq) } xen_irq_info_cleanup() { set_evtchn_to_irq(e, -1) } } Assume here event channel e refers here to the same event channel number. After this race the evtchn_to_irq mapping for e is invalid (-1). - __startup_pirq races with __unbind_from_irq in a similar way. Because __startup_pirq doesn't take irq_mapping_update_lock it can grab the evtchn that __unbind_from_irq is currently freeing and cleaning up. In this case even though the event channel is allocated, its mapping can be unset in evtchn_to_irq. The fix is to first cleanup the mappings and then close the event channel. • https://git.kernel.org/stable/c/d46a78b05c0e37f76ddf4a7a67bf0b6c68bada55 https://git.kernel.org/stable/c/9470f5b2503cae994098dea9682aee15b313fa44 https://git.kernel.org/stable/c/0fc88aeb2e32b76db3fe6a624b8333dbe621b8fd https://git.kernel.org/stable/c/ea592baf9e41779fe9a0424c03dd2f324feca3b3 https://git.kernel.org/stable/c/585a344af6bcac222608a158fc2830ff02712af5 https://git.kernel.org/stable/c/20980195ec8d2e41653800c45c8c367fa1b1f2b4 https://git.kernel.org/stable/c/9be71aa12afa91dfe457b3fb4a444c42b1ee036b https://git.kernel.org/stable/c/fa765c4b4aed2d64266b694520ecb025c •