Affected: Alpaquita:23: linux-lts, Alpaquita:stream: linux-lts

In the Linux kernel, the following vulnerability has been resolved:

ovl: fix null pointer dereference in ovl_get_acl_rcu()

Following process: P1 P2 path_openat link_path_walk may_lookup inode_permission(rcu) ovl_permission acl_permission_check check_acl get_cached_acl_rcu ovl_get_inode_acl realinode = ovl_inode_real(ovl_inode) drop_cache __dentry_kill(ovl_dentry) iput(ovl_inode) ovl_destroy_inode(ovl_inode) dput(oi->__upperdentry) dentry_kill(upperdentry) dentry_unlink_inode upperdentry->d_inode = NULL ovl_inode_upper upperdentry = ovl_i_dentry_upper(ovl_inode) d_inode(upperdentry) // returns NULL IS_POSIXACL(realinode) // NULL pointer dereference , will trigger an null pointer dereference at realinode: [ 205.472797] BUG: kernel NULL pointer dereference, address: 0000000000000028 [ 205.476701] CPU: 2 PID: 2713 Comm: ls Not tainted 6.3.0-12064-g2edfa098e750-dirty #1216 [ 205.478754] RIP: 0010:do_ovl_get_acl+0x5d/0x300 [ 205.489584] Call Trace: [ 205.489812] <TASK> [ 205.490014] ovl_get_inode_acl+0x26/0x30 [ 205.490466] get_cached_acl_rcu+0x61/0xa0 [ 205.490908] generic_permission+0x1bf/0x4e0 [ 205.491447] ovl_permission+0x79/0x1b0 [ 205.491917] inode_permission+0x15e/0x2c0 [ 205.49…

In the Linux kernel, the following vulnerability has been resolved:

ovl: fix null pointer dereference in ovl_get_acl_rcu()

Following process: P1 P2 path_openat link_path_walk may_lookup inode_permission(rcu) ovl_permission acl_permission_check check_acl get_cached_acl_rcu ovl_get_inode_acl realinode = ovl_inode_real(ovl_inode) drop_cache __dentry_kill(ovl_dentry) iput(ovl_inode) ovl_destroy_inode(ovl_inode) dput(oi->__upperdentry) dentry_kill(upperdentry) dentry_unlink_inode upperdentry->d_inode = NULL ovl_inode_upper upperdentry = ovl_i_dentry_upper(ovl_inode) d_inode(upperdentry) // returns NULL IS_POSIXACL(realinode) // NULL pointer dereference , will trigger an null pointer dereference at realinode: [ 205.472797] BUG: kernel NULL pointer dereference, address: 0000000000000028 [ 205.476701] CPU: 2 PID: 2713 Comm: ls Not tainted 6.3.0-12064-g2edfa098e750-dirty #1216 [ 205.478754] RIP: 0010:do_ovl_get_acl+0x5d/0x300 [ 205.489584] Call Trace: [ 205.489812] <TASK> [ 205.490014] ovl_get_inode_acl+0x26/0x30 [ 205.490466] get_cached_acl_rcu+0x61/0xa0 [ 205.490908] generic_permission+0x1bf/0x4e0 [ 205.491447] ovl_permission+0x79/0x1b0 [ 205.491917] inode_permission+0x15e/0x2c0 [ 205.49…

kernel: xen-netfront: Fix NULL sring after live migration kernel: fscache: Fix oops due to race with cookie_lru and use_cookie kernel: tracing: Free buffers when a used dynamic event is removed kernel: net: tun: Fix use-after-free in tun_detach() kernel: hwmon: (ibmpex) Fix possible UAF when ibmpex_register_bmc() fails kernel: erofs/zmap.c: Fix incorrect offset calculation kernel: arm64/mm: fix incorrect file_map_count for non-leaf pmd/pud kernel: s390: avoid using global register for current_stack_pointer kernel: erofs: fix missing xas_retry() in fscache mode kernel: rpmsg: qcom_smd: Fix refcount leak in qcom_smd_parse_edge kernel: remoteproc: k3-r5: Fix refcount leak in k3_r5_cluster_of_init kernel: of: check previous kernel's ima-kexec-buffer against memory bounds kernel: coresight: Clear the connection field properly kernel: Linux kernel: Denial of Service in coresight: trbe kernel: rpmsg: char: Avoid double destroy of default endpoint kernel: coresight: cti: Fix hang in cti_disable_hw() kernel: lib/fonts: fix undefined behavior in bit shift for get_default_font kernel: Kernel: Denial of Service in pci_endpoint_test due to zero-length DMA mapping kernel: Linux kernel: Denial of Service in erofs due to memory leak kernel: erofs: fix missing unmap if z_erofs_get_extent_compressedlen() fails kernel: pipe: wakeup wr_wait after setting max_usage kernel: ntb: intel: Fix the NULL vs IS_ERR() bug for debugfs_create_dir() kernel: qed/qed_sriov: guard against NULL derefs from qed_…

Security update for the Linux Kernel

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 110 more

In the Linux kernel, the following vulnerability has been resolved: ovl: fix null pointer dereference in ovl_get_acl_rcu() Following process: P1 P2 path_openat link_path_walk may_lookup inode_permission(rcu) ovl_permission acl_permission_check check_acl get_cached_acl_rcu ovl_get_inode_acl realinode = ovl_inode_real(ovl_inode) drop_cache __dentry_kill(ovl_dentry) iput(ovl_inode) ovl_destroy_inode(ovl_inode) dput(oi->__upperdentry) dentry_kill(upperdentry) dentry_unlink_inode upperdentry->d_inode = NULL ovl_inode_upper upperdentry = ovl_i_dentry_upper(ovl_inode) d_inode(upperdentry) // returns NULL IS_POSIXACL(realinode) // NULL pointer dereference , will trigger an null pointer dereference at realinode: [ 205.472797] BUG: kernel NULL pointer dereference, address: 0000000000000028 [ 205.476701] CPU: 2 PID: 2713 Comm: ls Not tainted 6.3.0-12064-g2edfa098e750-dirty #1216 [ 205.478754] RIP: 0010:do_ovl_get_acl+0x5d/0x300 [ 205.489584] Call Trace: [ 205.489812] <TASK> [ 205.490014] ovl_get_inode_acl+0x26/0x30 [ 205.490466] get_cached_acl_rcu+0x61/0xa0 [ 205.490908] generic_permission+0x1bf/0x4e0 [ 205.491447] ovl_permission+0x79/0x1b0 [ 205.491917] inode_permission+0x15e/0x2c0 [ 205.4924…

Ein Angreifer kann diese Schwachstellen ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen, die möglicherweise zu Denial‑of‑Service, Speicherbeschädigung oder weiteren nicht definierten Auswirkungen führen.