crash 7.2.6-1 source package in Ubuntu

Changelog

crash (7.2.6-1) unstable; urgency=medium

  * Two fixes for the Xen hypervisor; the first fixes a bug seen with Xen
    4.11.0 during initialization, which fails with the error message "crash:
    invalid kernel virtual address: <address> type: fill_pcpu_struct",
    followed by "WARNING: cannot fill pcpu_struct" and "crash: cannot read
    cpu_info".  The second fix prevents a segmentation violation associated
    with a crash-7.1.1 commit that addressed the Xen 4.5.0 hypervisor symbol
    name change from "dom0" to "hardware_domain".

  * Fix for Linux 4.20 and later x86_64 kernels which are NOT configured with
    CONFIG_RANDOMIZE_BASE.  Linux 4.20 introduced kernel commit
    d52888aa2753e3063a9d3a0c9f72f94aa9809c15, titled "x86/mm: Move LDT remap
    out of KASLR region on 5-level paging", which modified the 4-level and
    5-level paging PAGE_OFFSET values.  Without this patch, the crash session
    fails during initialization with the error message "crash: read error:
    kernel virtual address: <address>  type: tss_struct ist array".  For
    kernels prior to Linux 4.20.0 which have backports of the kernel commit,
    the kernel's PAGE_OFFSET value must be manually specified via the command
    line option "--machdep page_offset=ffff888000000000" for kernels with
    4-level page tables, or "--machdep page_offset=ff11000000000000" for
    kernels with 5-level paging.  (or alternatively the shorter version "-m
    page_offset=<address>" may be used).  The command line option requirement

  * Fix for the "p" command if the expression contains more than one opening
    parenthesis character and a minus/dash sign.  Without the patch, the
    minus/dash sign will get dropped from the command prior to it being passed
    on to gdb for evaluation, and the command will fail with the message "p:
    gdb request failed: <expression>", where the <expression> string will not

  * Fix for the internal parse_line() utility function to account for embedded
    sets of parentheses, which may be used for expressions that are passed to
    gdb by the "p" command.  Without the patch, expressions containing
    embedded sets of parentheses are broken up into multiple argument tokens
    instead of just one.  The previous commit has been reverted by this one.

  * First phase of support for ARM64 kernels that are configured with
    CONFIG_ARM64_USER_VA_BITS_52, which causes the PTRS_PER_PGD count to
    increase from 64 to 1024.  Without the patch, "WARNING: cannot access
    vmalloc'd module memory" will be displayed during session initialization,
    and the translation of any mapped kernel virtual address that requires a
    page table walk will fail, leading to a myriad of other errors.

  * Support for configurable CONFIG_ARM64_PA_BITS values introduced in kernel
    commit 982aa7c5f0861bf56b2412ca341a13f44c238ba4, titled "arm64: add
    kconfig symbol to configure physical address size".  Without the patch, it
    is impossible to determine the value of CONFIG_ARM64_PA_BITS is, and will
    require a new MAX_PHYSMEM_BITS vmcoreinfo entry to be exported.  This

  * For live system analysis where there is no vmcoreinfo ELF note attached to
    /proc/kcore, or for dumpfile analysis where there is no vmcoreinfo ELF
    note attached to the dumpfile, this patch sets the internal
    pc->read_vmcoreinfo() function to a new plugin function that reads the
    data directly from the live kernel or dumpfile.  Because the function is
    set much later during initialization than if the ELF note is attached to
    /proc/kcore or the dumpfile, it may not be available during very early

  * Fix for Linux 4.14.84 and later 4.14-based x86_64 kernels which are NOT
    configured with CONFIG_RANDOMIZE_BASE and have backported kernel commit
    d52888aa2753e3063a9d3a0c9f72f94aa9809c15, titled "x86/mm: Move LDT remap
    out of KASLR region on 5-level paging", which modified the 4-level and
    5-level paging PAGE_OFFSET values.  Without this patch, the crash session
    fails during initialization with the error message "crash: read error:
    kernel virtual address: <address>  type: tss_struct ist array".

  * Fix for determining the x86_64 "phys_base" value in dumpfiles created by
    the KVM "virsh dump" facility if the kernel is KASLR-enabled and does not
    have the phys_base value stored in vmcoreinfo data.  Without the patch,
    the message "WARNING: cannot determine physical base address: defaulting
    to 0" is displayed, and the crash session fails to initialize.

  * 32-bit ARM kernels built with the Thumb-2 instruction set utilize the R7
    register instead of FP for unwinding stacks using the DWARF unwinder.  On
    those kernels, without the patch, the "bt" command only shows the task

  * Fix for the "kmem -z" option on Linux 5.0 and later kernels that contain
    commit a921444382b49cc7fdeca3fba3e278bc09484a27, titled "mm: move zone
    watermark accesses behind an accessor".  Without the patch, the command
    fails with the error message "kmem: invalid (optional) structure member
    offsets: zone_pages_min or zone_struct_pages_min".

  * Fix for the "kmem -i" option on Linux 5.0 and later kernels that contain
    commit ca79b0c211af63fa3276f0e3fd7dd9ada2439839 titled "mm: convert
    totalram_pages and totalhigh_pages variables to atomic".  Without the
    patch, the command prints some incorrect values, and besides does not
    print high/low memory information on kernels which are configured with

  * Fix for the display of kernel module symbol types by the "sym" command in
    Linux 5.0 and later kernels if the module debuginfo data has not been
    loaded into the crash session.  The st_info member of the Elf32_Sym or
    Elf64_Sym structures has changed so as to not contain ASCII symbol type
    characters, and as a result the "sym" command will show unprintable data
    as the symbol type.  With the patch, only text types ("t" or "T") will be

  * First phase of support of the upcoming ARM64 kernel memory map changes to
    support 52-bit kernel virtual addressing, which allows the configuration
    of CONFIG_ARM64_VA_BITS to be 52, but where the actual number of VA bits
    may be downgraded during boot depending upon the hardware capability.
    This phase is only applicable for live system analysis.

  * Fix for the "dis <function>" option with kernel module text symbols on
    Linux 5.0 and later kernels.  Without the patch, the disassembly may stop
    prematurely or extend into the next function because the st_size member of
    the Elf32_Sym or Elf64_Sym text symbol structures can no longer be used as

  * Commit dd12805ed1db7 in the linux-next kernel repository, titled "XArray:
    Remove radix tree compatibility", changes the definition of
    "radix_tree_root" back to be a struct.  However, the content of the new
    structure differs from the original structure, so without the patch,
    current linux-next kernels fail during initialization with the error
    message "radix trees do not exist or have changed their format".  Because
    the new "radix_tree_root" and "xarray" structures have nearly the same
    layout, the existing functionality for XArrays can be reused.

  * Fixes for the "trace.so" extension module: (1) The reader_page can be
    empty if it was never read, do not record it if it is empty. Better yet,
    do not record any page that is empty.  The struct buffer_page "real_end"
    is not available in older kernels, so it needs to be tested if it exists
    before we can use it.  (2) In newer kernels, the sp->type of kernel module
    symbols does not contain the symbol type character unless the module's
    debuginfo data has been loaded into the crash session.  Writing a garbage
    type to the kallsyms file for trace-cmd to read causes it to crash, so
    just always write an 'm'.  (3) Add the "trace dump -t <trace.dat>" option

  * Fix to find the kernel configuration data in Linux 5.1 kernels containing
    commit 13610aa908dcfce77135bb799c0a10d0172da6ba, titled "kernel/configs:
    use .incbin directive to embed config_data.gz".  Without the patch, new
    kernels configured with CONFIG_IKCONFIG_PROC will display "WARNING: could
    not find MAGIC_START!" during session initialization, and also when

  * Fix for the PPC64 "bt" command running against kernels that are configured
    with CONFIG_THREAD_INFO_IN_TASK.  Without the patch, the "bt" command
    fails with the message "bt: invalid/stale stack pointer for this task:

  * Fix for the "files -d <dentry>" option if the dentry.d_inode pointer is
    NULL.  Without the patch, the command output does not display the

  * When the is_s390_dump() function is called to determine whether a file is
    an s390 dumpfile, it currently presumes that the fopen() call always
    works, and then tries to read it with using a NULL file pointer.  Change
    it to verify that the fopen() was successful, and if not, print an error
    message as is done with the other dumpfile type verifier functions.

  * Implement support for ARM64 kernels that are configured with:
    CONFIG_ARM64_PA_BITS=52 CONFIG_ARM64_64K_PAGES CONFIG_PGTABLE_LEVELS=3 and
    that run on a host containing physical memory that utilizes any bit in the
    uppermost 4 bits of the 52-bit physical address range.

  * Extension of the "snap.so" extension module to pass a second
    architecture-specific value in the ELF header; its initial use is for
    support of the upcoming ARM64 52-bit kernel virtual address space by

  * Apply initial changes to support kernel address space layout randomization
    (KASLR) for s390X.  This is the minimal patch-set required to process
    s390x dumps for the kernels configured with CONFIG_RANDOMIZE_BASE, and to
    accept the "--kaslr" command line option.  Only dumpfiles whose headers

  * Fix for the "dev -[dD]" options on Linux 5.1-rc1 and later kernels that
    contain commit 570d0200123fb4f809aa2f6226e93a458d664d70, titled "driver
    core: move device->knode_class to device_private".  Without the patch, the
    command options fail with the error message "dev: invalid structure member

  * Linux 4.18 kernels introduced a new CONFIG_PROC_VMCORE_DEVICE_DUMP
    configuration in commit 2724273e8fd00b512596a77ee063f49b25f36507, titled
    "vmcore: add API to collect hardware dump in second kernel", in which
    device drivers may collect a device specific snapshot of the
    hardware/firmware state of their underlying devices, and export the data
    as a kdump ELF note with type NT_VMCOREDD.  This patch recognizes the new
    ELF note(s) in both ELF and compressed kdump vmcore dumpfiles.  The "help
    -[nD]" option shows basic information about each note, and two new "dev"
    command options have been introduced.  The "dev -V" option displays an
    indexed list of each note, showing the device name, the dumpfile offset,
    and the size of each note.  The "dev -v index [file]" option either dumps
    the contents of a note to the display screen in a human-readable format,
    or copies the note data directly to a specified file.

  * If the kernel's "vmap_area_list" doubly-linked list is corrupt such that
    it does not link back to the global list_head, commands that require
    information regarding the range of virtually-mapped kernel addresses will
    display a generic list-handling error message such as "kmem: invalid list
    entry: 0", and the command will typically fail to fully complete.
    However, without the patch, there will also be "WARNING: malloc/free
    mismatch (29/30)" messages that get displayed after every subsequent
    command.  This patch prevents the mismatch messages, and also adds an
    additional error message indicating "WARNING: invalid/corrupt
    vmap_area_list" to further clarify the generic list-handling error

  * Fix for the "dev" help page to remove the unused -r option letter.

  * If a duplicate list entry is encountered when using the "list -B" Brent
    algorithm, change the list loop length value from hexadecimal to decimal.

  * Update the README file to indicate the capability of building an x86_64
    crash binary with "make target=PPC64", which can be used to analyze

  * Fix for hybrid kernels that have backported support for the Xarray
    facility while allowing subsystems to continue to use radix trees.
    Without the patch, the crash session fails during initialization with the
    message "crash: xarray facility does not exist or has changed its format".

 -- Troy Heber <email address hidden>  Mon, 15 Jul 2019 08:20:49 -0600