In the Linux kernel, the following vulnerability has been resolved:
mm: khugepaged: skip huge page collapse for special files
The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2].
This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface.
[shy828301@gmail.com: fix vm_file check [3]]
In the Linux kernel, the following vulnerability has been resolved:
mm: khugepaged: skip huge page collapse for special files
The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2].
This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface.
[shy828301@gmail.com: fix vm_file check [3]]
kernel: tracing: Restructure trace_clock_global() to never block kernel: ensure definition of the fixmap area is in a limit kernel: net: ieee802154: fix null deref in parse dev addr kernel: isdn: mISDN: netjet: Fix crash in nj_probe kernel: tcp: fix tcp_init_transfer() to not reset icsk_ca_initialized kernel: irqchip/gic-v3-its: Fix potential VPE leak on error kernel: netfilter: conntrack: serialize hash resizes and cleanups kernel: userfaultfd: fix a race between writeprotect and exit_mmap() kernel: isdn: mISDN: Fix sleeping function called from invalid context kernel: mm: khugepaged: skip huge page collapse for special files kernel: ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port() kernel: ovl: fix warning in ovl_create_real() kernel: net/sunrpc: fix reference count leaks in rpc_sysfs_xprt_state_change kernel: i2c: mlxbf: prevent stack overflow in mlxbf_i2c_smbus_start_transaction() kernel: net: amd-xgbe: Fix skb data length underflow kernel: block: Fix wrong offset in bio_truncate() kernel: net: fix information leakage in /proc/net/ptype kernel: cifs: Fix memory leak when build ntlmssp negotiate blob failed kernel: x86/xen: Fix memory leak in xen_smp_intr_init{_pv}() kernel: Local information disclosure on Intel(R) Atom(R) processors kernel: powerpc: Fix access beyond end of drmem array kernel: efivarfs: force RO when remounting if SetVariable is not supported kernel: use-after-free in kv_parse_power_table kernel: null po…
kernel: tracing: Restructure trace_clock_global() to never block kernel: net: ieee802154: fix null deref in parse dev addr kernel: isdn: mISDN: netjet: Fix crash in nj_probe kernel: tcp: fix tcp_init_transfer() to not reset icsk_ca_initialized kernel: irqchip/gic-v3-its: Fix potential VPE leak on error kernel: netfilter: conntrack: serialize hash resizes and cleanups kernel: userfaultfd: fix a race between writeprotect and exit_mmap() kernel: isdn: mISDN: Fix sleeping function called from invalid context kernel: mm: khugepaged: skip huge page collapse for special files kernel: ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port() kernel: ovl: fix warning in ovl_create_real() kernel: net/sunrpc: fix reference count leaks in rpc_sysfs_xprt_state_change kernel: i2c: mlxbf: prevent stack overflow in mlxbf_i2c_smbus_start_transaction() kernel: net: amd-xgbe: Fix skb data length underflow kernel: block: Fix wrong offset in bio_truncate() kernel: net: fix information leakage in /proc/net/ptype kernel: efivarfs: force RO when remounting if SetVariable is not supported kernel: use-after-free in kv_parse_power_table kernel: null pointer dereference issues in ice_ptp.c kernel: drm: Don't unref the same fb many times by mistake due to deadlock handling kernel: wifi: mac80211: fix potential key use-after-free kernel: pstore/ram: Fix crash when setting number of cpus to an odd number kernel: ext4: avoid online resizing failures due to oversiz…
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:Pro:18.04:LTS: linux-aws-5.4, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:Pro:18.04:LTS: linux-azure-5.4, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3 and 83 more
In the Linux kernel, the following vulnerability has been resolved: mm: khugepaged: skip huge page collapse for special files The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2]. This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface. [shy828301@gmail.com: fix vm_file check [3]]
Ein lokaler Angreifer kann mehrere Schwachstellen im Linux-Kernel ausnutzen, um einen Denial-of-Service-Zustand zu erzeugen oder unspezifische Angriffe durchzuführen.