An issue was discovered in the Linux kernel through 4.17.11, as used in Xen through 4.11.x. The xen_failsafe_callback entry point in arch/x86/entry/entry_64.S does not properly maintain RBX, which allows local users to cause a denial of service (uninitialized memory usage and system crash). Within Xen, 64-bit x86 PV Linux guest OS users can trigger a guest OS crash or possibly gain privileges.
An issue was discovered in the Linux kernel through 4.17.10. There is a NULL pointer dereference and panic in hfsplus_lookup() in fs/hfsplus/dir.c when opening a file (that is purportedly a hard link) in an hfs+ filesystem that has malformed catalog data, and is mounted read-only without a metadata directory.
An issue was discovered in the Linux kernel through 4.17.10. There is a buffer overflow in truncate_inline_inode() in fs/f2fs/inline.c when umounting an f2fs image, because a length value may be negative.
An issue was discovered in the Linux kernel through 4.17.10. There is an out-of-bounds access in __remove_dirty_segment() in fs/f2fs/segment.c when mounting an f2fs image.
An issue was discovered in the Linux kernel through 4.17.10. There is an invalid pointer dereference in io_ctl_map_page() when mounting and operating a crafted btrfs image, because of a lack of block group item validation in check_leaf_item in fs/btrfs/tree-checker.c.
An issue was discovered in the Linux kernel through 4.17.10. There is an invalid pointer dereference in btrfs_root_node() when mounting a crafted btrfs image, because of a lack of chunk block group mapping validation in btrfs_read_block_groups in fs/btrfs/extent-tree.c, and a lack of empty-tree checks in check_leaf in fs/btrfs/tree-checker.c.
An issue was discovered in the Linux kernel through 4.17.10. There is a use-after-free in try_merge_free_space() when mounting a crafted btrfs image, because of a lack of chunk type flag checks in btrfs_check_chunk_valid in fs/btrfs/volumes.c.
An issue was discovered in the Linux kernel through 4.17.10. There is out-of-bounds access in write_extent_buffer() when mounting and operating a crafted btrfs image, because of a lack of verification that each block group has a corresponding chunk at mount time, within btrfs_read_block_groups in fs/btrfs/extent-tree.c.
An issue was discovered in the Linux kernel through 4.17.10. There is an invalid pointer dereference in __del_reloc_root() in fs/btrfs/relocation.c when mounting a crafted btrfs image, related to removing reloc rb_trees when reloc control has not been initialized.
An issue was discovered in fs/f2fs/super.c in the Linux kernel through 4.17.3, which does not properly validate secs_per_zone in a corrupted f2fs image, as demonstrated by a divide-by-zero error.
An issue was discovered in fs/f2fs/inline.c in the Linux kernel through 4.4. A denial of service (out-of-bounds memory access and BUG) can occur for a modified f2fs filesystem image in which an inline inode contains an invalid reserved blkaddr.
An issue was discovered in fs/f2fs/inode.c in the Linux kernel through 4.17.3. A denial of service (slab out-of-bounds read and BUG) can occur for a modified f2fs filesystem image in which FI_EXTRA_ATTR is set in an inode.
An issue was discovered in fs/f2fs/super.c in the Linux kernel through 4.17.3. There is an out-of-bounds read or a divide-by-zero error for an incorrect user_block_count in a corrupted f2fs image, leading to a denial of service (BUG).
An issue was discovered in fs/f2fs/super.c in the Linux kernel through 4.14. A denial of service (out-of-bounds memory access and BUG) can occur upon encountering an abnormal bitmap size when mounting a crafted f2fs image.
An issue was discovered in fs/xfs/libxfs/xfs_inode_buf.c in the Linux kernel through 4.17.3. A denial of service (memory corruption and BUG) can occur for a corrupted xfs image upon encountering an inode that is in extent format, but has more extents than fit in the inode fork.
An issue was discovered in fs/xfs/xfs_icache.c in the Linux kernel through 4.17.3. There is a NULL pointer dereference and panic in lookup_slow() on a NULL inode->i_ops pointer when doing pathwalks on a corrupted xfs image. This occurs because of a lack of proper validation that cached inodes are free during allocation.
The alarm_timer_nsleep function in kernel/time/alarmtimer.c in the Linux kernel through 4.17.3 has an integer overflow via a large relative timeout because ktime_add_safe is not used.
In the function wmi_set_ie(), the length validation code does not handle unsigned integer overflow properly. As a result, a large value of the 'ie_len' argument can cause a buffer overflow in all Android releases from CAF (Android for MSM, Firefox OS for MSM, QRD Android) using the Linux Kernel.
Xen allows guest OS users to obtain sensitive information from uninitialized locations in host OS kernel memory by not enabling memory and I/O decoding control bits. NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-0777.