A flaw was found in the Linux kernel's implementation of ext4 extent management. The kernel doesn't correctly initialize memory regions in the extent tree block which may be exported to a local user to obtain sensitive information by reading empty/uninitialized data from the filesystem.

An information leakage issue was found in the way Linux kernel's KVM hypervisor handled page fault exception while emulating instructions like VMXON, VMCLEAR, VMPTRLD, VMWRITE with memory address as an operand. It occurs if the operand is an mmio address, as the returned exception object holds uninitialised stack memory contents.

A guest user/process could use this flaw to leak host's stack memory contents to a guest.

It affects only Intel processors and only when nested virtualization is enabled.

Upstream patch: --------------- -> https://git.kernel.org/linus/353c0956a618a07ba4bbe7ad00ff29fe70e8412a

Reference: ---------- -> https://www.openwall.com/lists/oss-security/2019/02/18/2

A flaw was found in the Linux kernel's implementation of logical link control and adaptation protocol (L2CAP), part of the Bluetooth stack in the l2capparseconfrsp and l2capparseconfreq functions. An attacker with physical access within the range of standard Bluetooth transmission can create a specially crafted packet. The response to this specially crafted packet can contain part of the kernel stack which can be used in a further attack.

A flaw was found in the Linux kernel's implementation of Logical Link Control and Adaptation Protocol (L2CAP), part of the Bluetooth stack. An attacker, within the range of standard Bluetooth transmissions, can create and send a specially crafted packet. The response to this specially crafted packet can contain part of the kernel stack which can be used in a further attack.