06 Dec, 2018
4 commits
-
In kdump case, there exists only one dedicated memblock region as usable
memory (crashk_res). With this patch, kexec_walk_memblock() runs a given
callback function on this region.Cosmetic change: 0 to MEMBLOCK_NONE at for_each_free_mem_range*()
Signed-off-by: AKASHI Takahiro
Acked-by: Dave Young
Cc: Vivek Goyal
Cc: Baoquan He
Signed-off-by: Will Deacon -
Memblock list is another source for usable system memory layout.
So move powerpc's arch_kexec_walk_mem() to common code so that other
memblock-based architectures, particularly arm64, can also utilise it.
A moved function is now renamed to kexec_walk_memblock() and integrated
into kexec_locate_mem_hole(), which will now be usable for all
architectures with no need for overriding arch_kexec_walk_mem().With this change, arch_kexec_walk_mem() need no longer be a weak function,
and was now renamed to kexec_walk_resources().Since powerpc doesn't support kdump in its kexec_file_load(), the current
kexec_walk_memblock() won't work for kdump either in this form, this will
be fixed in the next patch.Signed-off-by: AKASHI Takahiro
Cc: "Eric W. Biederman"
Acked-by: Dave Young
Cc: Vivek Goyal
Cc: Baoquan He
Acked-by: James Morse
Signed-off-by: Will Deacon -
Since s390 already knows where to locate buffers, calling
arch_kexec_mem_walk() has no sense. So we can just drop it as kbuf->mem
indicates this while all other architectures sets it to 0 initially.This change is a preparatory work for the next patch, where all the
variant memory walks, either on system resource or memblock, will be
put in one common place so that it will satisfy all the architectures'
need.Signed-off-by: AKASHI Takahiro
Reviewed-by: Philipp Rudo
Cc: Martin Schwidefsky
Cc: Heiko Carstens
Cc: Dave Young
Cc: Vivek Goyal
Cc: Baoquan He
Signed-off-by: Will Deacon -
Change this function from static to global so that arm64 can implement
its own arch_kimage_file_post_load_cleanup() later using
kexec_image_post_load_cleanup_default().Signed-off-by: AKASHI Takahiro
Acked-by: Dave Young
Cc: Vivek Goyal
Cc: Baoquan He
Signed-off-by: Will Deacon
04 Nov, 2018
1 commit
-
We include kexec.h and slab.h twice in kexec_file.c. It's unnecessary.
hence just remove them.Link: http://lkml.kernel.org/r/1537498098-19171-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang
Reviewed-by: Bhupesh Sharma
Reviewed-by: Andrew Morton
Acked-by: Baoquan He
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
13 Jun, 2018
1 commit
-
The vzalloc() function has no 2-factor argument form, so multiplication
factors need to be wrapped in array_size(). This patch replaces cases of:vzalloc(a * b)
with:
vzalloc(array_size(a, b))as well as handling cases of:
vzalloc(a * b * c)
with:
vzalloc(array3_size(a, b, c))
This does, however, attempt to ignore constant size factors like:
vzalloc(4 * 1024)
though any constants defined via macros get caught up in the conversion.
Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.The Coccinelle script used for this was:
// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@(
vzalloc(
- (sizeof(TYPE)) * E
+ sizeof(TYPE) * E
, ...)
|
vzalloc(
- (sizeof(THING)) * E
+ sizeof(THING) * E
, ...)
)// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@(
vzalloc(
- sizeof(u8) * (COUNT)
+ COUNT
, ...)
|
vzalloc(
- sizeof(__u8) * (COUNT)
+ COUNT
, ...)
|
vzalloc(
- sizeof(char) * (COUNT)
+ COUNT
, ...)
|
vzalloc(
- sizeof(unsigned char) * (COUNT)
+ COUNT
, ...)
|
vzalloc(
- sizeof(u8) * COUNT
+ COUNT
, ...)
|
vzalloc(
- sizeof(__u8) * COUNT
+ COUNT
, ...)
|
vzalloc(
- sizeof(char) * COUNT
+ COUNT
, ...)
|
vzalloc(
- sizeof(unsigned char) * COUNT
+ COUNT
, ...)
)// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@(
vzalloc(
- sizeof(TYPE) * (COUNT_ID)
+ array_size(COUNT_ID, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * COUNT_ID
+ array_size(COUNT_ID, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * (COUNT_CONST)
+ array_size(COUNT_CONST, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * COUNT_CONST
+ array_size(COUNT_CONST, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(THING) * (COUNT_ID)
+ array_size(COUNT_ID, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * COUNT_ID
+ array_size(COUNT_ID, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * (COUNT_CONST)
+ array_size(COUNT_CONST, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * COUNT_CONST
+ array_size(COUNT_CONST, sizeof(THING))
, ...)
)// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@vzalloc(
- SIZE * COUNT
+ array_size(COUNT, SIZE)
, ...)// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@(
vzalloc(
- sizeof(TYPE) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(THING) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
)// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@(
vzalloc(
- sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
vzalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
vzalloc(
- sizeof(THING1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
vzalloc(
- sizeof(THING1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
vzalloc(
- sizeof(TYPE1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
|
vzalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
)// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@(
vzalloc(
- (COUNT) * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- COUNT * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- COUNT * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- (COUNT) * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- COUNT * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- (COUNT) * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- (COUNT) * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- COUNT * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
)// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@(
vzalloc(C1 * C2 * C3, ...)
|
vzalloc(
- E1 * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
)// And then all remaining 2 factors products when they're not all constants.
@@
expression E1, E2;
constant C1, C2;
@@(
vzalloc(C1 * C2, ...)
|
vzalloc(
- E1 * E2
+ array_size(E1, E2)
, ...)
)Signed-off-by: Kees Cook
14 Apr, 2018
12 commits
-
For s390 new kernels are loaded to fixed addresses in memory before they
are booted. With the current code this is a problem as it assumes the
kernel will be loaded to an 'arbitrary' address. In particular,
kexec_locate_mem_hole searches for a large enough memory region and sets
the load address (kexec_bufer->mem) to it.Luckily there is a simple workaround for this problem. By returning 1
in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off. This
allows the architecture to set kbuf->mem by hand. While the trick works
fine for the kernel it does not for the purgatory as here the
architectures don't have access to its kexec_buffer.Give architectures access to the purgatories kexec_buffer by changing
kexec_load_purgatory to take a pointer to it. With this change
architectures have access to the buffer and can edit it as they need.A nice side effect of this change is that we can get rid of the
purgatory_info->purgatory_load_address field. As now the information
stored there can directly be accessed from kbuf->mem.Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Reviewed-by: Martin Schwidefsky
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The current code uses the sh_offset field in purgatory_info->sechdrs to
store a pointer to the current load address of the section. Depending
whether the section will be loaded or not this is either a pointer into
purgatory_info->purgatory_buf or kexec_purgatory. This is not only a
violation of the ELF standard but also makes the code very hard to
understand as you cannot tell if the memory you are using is read-only
or not.Remove this misuse and store the offset of the section in
pugaroty_info->purgatory_buf in sh_offset.Link: http://lkml.kernel.org/r/20180321112751.22196-10-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The main loop currently uses quite a lot of variables to update the
section headers. Some of them are unnecessary. So clean them up a
little.Link: http://lkml.kernel.org/r/20180321112751.22196-9-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
To update the entry point there is an extra loop over all section
headers although this can be done in the main loop. So move it there
and eliminate the extra loop and variable to store the 'entry section
index'.Also, in the main loop, move the usual case, i.e. non-bss section, out
of the extra if-block.Link: http://lkml.kernel.org/r/20180321112751.22196-8-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Reviewed-by: Martin Schwidefsky
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When inspecting __kexec_load_purgatory you find that it has two tasks
1) setting up the kexec_buffer for the new kernel and,
2) setting up pi->sechdrs for the final load address.The two tasks are independent of each other. To improve readability
split up __kexec_load_purgatory into two functions, one for each task,
and call them directly from kexec_load_purgatory.Link: http://lkml.kernel.org/r/20180321112751.22196-7-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When the relocations are applied to the purgatory only the section the
relocations are applied to is writable. The other sections, i.e. the
symtab and .rel/.rela, are in read-only kexec_purgatory. Highlight this
by marking the corresponding variables as 'const'.While at it also change the signatures of arch_kexec_apply_relocations* to
take section pointers instead of just the index of the relocation section.
This removes the second lookup and sanity check of the sections in arch
code.Link: http://lkml.kernel.org/r/20180321112751.22196-6-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The stripped purgatory does not contain a symtab. So when looking for
symbols this is done in read-only kexec_purgatory. Highlight this by
marking the corresponding variables as 'const'.Link: http://lkml.kernel.org/r/20180321112751.22196-5-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The kexec_purgatory buffer is read-only. Thus all pointers into
kexec_purgatory are read-only, too. Point this out by explicitly
marking purgatory_info->ehdr as 'const' and update the comments in
purgatory_info.Link: http://lkml.kernel.org/r/20180321112751.22196-4-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Before the purgatory is loaded several checks are done whether the ELF
file in kexec_purgatory is valid or not. These checks are incomplete.
For example they don't check for the total size of the sections defined
in the section header table or if the entry point actually points into
the purgatory.On the other hand the purgatory, although an ELF file on its own, is
part of the kernel. Thus not trusting the purgatory means not trusting
the kernel build itself.So remove all validity checks on the purgatory and just trust the kernel
build.Link: http://lkml.kernel.org/r/20180321112751.22196-3-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo
Acked-by: Dave Young
Cc: AKASHI Takahiro
Cc: Eric Biederman
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Martin Schwidefsky
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Cc: Vivek Goyal
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In the previous patches, commonly-used routines, exclude_mem_range() and
prepare_elf64_headers(), were carved out. Now place them in kexec
common code. A prefix "crash_" is given to each of their names to avoid
possible name collisions.Link: http://lkml.kernel.org/r/20180306102303.9063-8-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro
Acked-by: Dave Young
Tested-by: Dave Young
Cc: Vivek Goyal
Cc: Baoquan He
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
As arch_kexec_kernel_image_{probe,load}(),
arch_kimage_file_post_load_cleanup() and arch_kexec_kernel_verify_sig()
are almost duplicated among architectures, they can be commonalized with
an architecture-defined kexec_file_ops array. So let's factor them out.Link: http://lkml.kernel.org/r/20180306102303.9063-3-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro
Acked-by: Dave Young
Tested-by: Dave Young
Cc: Vivek Goyal
Cc: Baoquan He
Cc: Michael Ellerman
Cc: Thiago Jung Bauermann
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Patch series "kexec_file, x86, powerpc: refactoring for other
architecutres", v2.This is a preparatory patchset for adding kexec_file support on arm64.
It was originally included in a arm64 patch set[1], but Philipp is also
working on their kexec_file support on s390[2] and some changes are now
conflicting.So these common parts were extracted and put into a separate patch set
for better integration. What's more, my original patch#4 was split into
a few small chunks for easier review after Dave's comment.As such, the resulting code is basically identical with my original, and
the only *visible* differences are:- renaming of _kexec_kernel_image_probe() and _kimage_file_post_load_cleanup()
- change one of types of arguments at prepare_elf64_headers()
Those, unfortunately, require a couple of trivial changes on the rest
(#1, #6 to #13) of my arm64 kexec_file patch set[1].Patch #1 allows making a use of purgatory optional, particularly useful
for arm64.Patch #2 commonalizes arch_kexec_kernel_{image_probe, image_load,
verify_sig}() and arch_kimage_file_post_load_cleanup() across
architectures.Patches #3-#7 are also intended to generalize parse_elf64_headers(),
along with exclude_mem_range(), to be made best re-use of.[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-February/561182.html
[2] http://lkml.iu.edu//hypermail/linux/kernel/1802.1/02596.htmlThis patch (of 7):
On arm64, crash dump kernel's usable memory is protected by *unmapping*
it from kernel virtual space unlike other architectures where the region
is just made read-only. It is highly unlikely that the region is
accidentally corrupted and this observation rationalizes that digest
check code can also be dropped from purgatory. The resulting code is so
simple as it doesn't require a bit ugly re-linking/relocation stuff,
i.e. arch_kexec_apply_relocations_add().Please see:
http://lists.infradead.org/pipermail/linux-arm-kernel/2017-December/545428.html
All that the purgatory does is to shuffle arguments and jump into a new
kernel, while we still need to have some space for a hash value
(purgatory_sha256_digest) which is never checked against.As such, it doesn't make sense to have trampline code between old kernel
and new kernel on arm64.This patch introduces a new configuration, ARCH_HAS_KEXEC_PURGATORY, and
allows related code to be compiled in only if necessary.[takahiro.akashi@linaro.org: fix trivial screwup]
Link: http://lkml.kernel.org/r/20180309093346.GF25863@linaro.org
Link: http://lkml.kernel.org/r/20180306102303.9063-2-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro
Acked-by: Dave Young
Tested-by: Dave Young
Cc: Vivek Goyal
Cc: Baoquan He
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Nov, 2017
1 commit
-
In preperation for a new function that will need additional resource
information during the resource walk, update the resource walk callback to
pass the resource structure. Since the current callback start and end
arguments are pulled from the resource structure, the callback functions
can obtain them from the resource structure directly.Signed-off-by: Tom Lendacky
Signed-off-by: Brijesh Singh
Signed-off-by: Thomas Gleixner
Reviewed-by: Kees Cook
Reviewed-by: Borislav Petkov
Tested-by: Borislav Petkov
Cc: kvm@vger.kernel.org
Cc: Benjamin Herrenschmidt
Cc: Borislav Petkov
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lkml.kernel.org/r/20171020143059.3291-10-brijesh.singh@amd.com
13 Jul, 2017
2 commits
-
Defining kexec_purgatory as a zero-length char array upsets compile time
size checking. Since this is built on a per-arch basis, define it as an
unsized char array (like is done for other similar things, e.g. linker
sections). This silences the warning generated by the future
CONFIG_FORTIFY_SOURCE, which did not like the memcmp() of a "0 byte"
array. This drops the __weak and uses an extern instead, since both
users define kexec_purgatory.Link: http://lkml.kernel.org/r/1497903987-21002-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook
Acked-by: "Eric W. Biederman"
Cc: Daniel Micay
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently vmcoreinfo data is updated at boot time subsys_initcall(), it
has the risk of being modified by some wrong code during system is
running.As a result, vmcore dumped may contain the wrong vmcoreinfo. Later on,
when using "crash", "makedumpfile", etc utility to parse this vmcore, we
probably will get "Segmentation fault" or other unexpected errors.E.g. 1) wrong code overwrites vmcoreinfo_data; 2) further crashes the
system; 3) trigger kdump, then we obviously will fail to recognize the
crash context correctly due to the corrupted vmcoreinfo.Now except for vmcoreinfo, all the crash data is well
protected(including the cpu note which is fully updated in the crash
path, thus its correctness is guaranteed). Given that vmcoreinfo data
is a large chunk prepared for kdump, we better protect it as well.To solve this, we relocate and copy vmcoreinfo_data to the crash memory
when kdump is loading via kexec syscalls. Because the whole crash
memory will be protected by existing arch_kexec_protect_crashkres()
mechanism, we naturally protect vmcoreinfo_data from write(even read)
access under kernel direct mapping after kdump is loaded.Since kdump is usually loaded at the very early stage after boot, we can
trust the correctness of the vmcoreinfo data copied.On the other hand, we still need to operate the vmcoreinfo safe copy
when crash happens to generate vmcoreinfo_note again, we rely on vmap()
to map out a new kernel virtual address and update to use this new one
instead in the following crash_save_vmcoreinfo().BTW, we do not touch vmcoreinfo_note, because it will be fully updated
using the protected vmcoreinfo_data after crash which is surely correct
just like the cpu crash note.Link: http://lkml.kernel.org/r/1493281021-20737-3-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang
Tested-by: Michael Holzheu
Cc: Benjamin Herrenschmidt
Cc: Dave Young
Cc: Eric Biederman
Cc: Hari Bathini
Cc: Juergen Gross
Cc: Mahesh Salgaonkar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
30 Jun, 2017
1 commit
-
Signed-off-by: Al Viro
11 Mar, 2017
1 commit
-
The purgatory code defines global variables which are referenced via a
symbol lookup in the kexec code (core and arch).A recent commit addressing sparse warnings made these static and thereby
broke kexec_file.Why did this happen? Simply because the whole machinery is undocumented and
lacks any form of forward declarations. The variable names are unspecific
and lack a prefix, so adding forward declarations creates shadow variables
in the core code. Aside of that the code relies on magic constants and
duplicate struct definitions with no way to ensure that these things stay
in sync. The section placement of the purgatory variables happened by
chance and not by design.Unbreak kexec and cleanup the mess:
- Add proper forward declarations and document the usage
- Use common struct definition
- Use the proper common defines instead of magic constants
- Add a purgatory_ prefix to have a proper name space
- Use ARRAY_SIZE() instead of a homebrewn reimplementation
- Add proper sections to the purgatory variables [ From Mike ]Fixes: 72042a8c7b01 ("x86/purgatory: Make functions and variables static")
Reported-by: Mike Galbraith <
Signed-off-by: Thomas Gleixner
Cc: Nicholas Mc Guire
Cc: Borislav Petkov
Cc: Vivek Goyal
Cc: "Tobin C. Harding"
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1703101315140.3681@nanos
Signed-off-by: Thomas Gleixner
21 Dec, 2016
1 commit
-
The TPM PCRs are only reset on a hard reboot. In order to validate a
TPM's quote after a soft reboot (eg. kexec -e), the IMA measurement
list of the running kernel must be saved and restored on boot.This patch uses the kexec buffer passing mechanism to pass the
serialized IMA binary_runtime_measurements to the next kernel.Link: http://lkml.kernel.org/r/1480554346-29071-7-git-send-email-zohar@linux.vnet.ibm.com
Signed-off-by: Thiago Jung Bauermann
Signed-off-by: Mimi Zohar
Acked-by: "Eric W. Biederman"
Acked-by: Dmitry Kasatkin
Cc: Andreas Steffen
Cc: Josh Sklar
Cc: Dave Young
Cc: Vivek Goyal
Cc: Baoquan He
Cc: Michael Ellerman
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Stewart Smith
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
30 Nov, 2016
3 commits
-
kexec_locate_mem_hole will be used by the PowerPC kexec_file_load
implementation to find free memory for the purgatory stack.Signed-off-by: Thiago Jung Bauermann
Acked-by: Dave Young
Signed-off-by: Michael Ellerman -
This is done to simplify the kexec_add_buffer argument list.
Adapt all callers to set up a kexec_buf to pass to kexec_add_buffer.In addition, change the type of kexec_buf.buffer from char * to void *.
There is no particular reason for it to be a char *, and the change
allows us to get rid of 3 existing casts to char * in the code.Signed-off-by: Thiago Jung Bauermann
Acked-by: Dave Young
Acked-by: Balbir Singh
Signed-off-by: Michael Ellerman -
Allow architectures to specify a different memory walking function for
kexec_add_buffer. x86 uses iomem to track reserved memory ranges, but
PowerPC uses the memblock subsystem.Signed-off-by: Thiago Jung Bauermann
Acked-by: Dave Young
Acked-by: Balbir Singh
Signed-off-by: Michael Ellerman
02 Sep, 2016
1 commit
-
If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs
and pi->purgatory_buf. This is redundant, because in case of error
kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which
will also free those buffers.This causes two warnings like the following, one for pi->sechdrs and the
other for pi->purgatory_buf:kexec-bzImage64: Loading purgatory failed
------------[ cut here ]------------
WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0
Trying to vfree() nonexistent vm area (ffffc90000e91000)
Modules linked in:
CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
dump_stack+0x4d/0x65
__warn+0xcb/0xf0
warn_slowpath_fmt+0x4f/0x60
? find_vmap_area+0x19/0x70
? kimage_file_post_load_cleanup+0x47/0xb0
__vunmap+0xc1/0xd0
vfree+0x2e/0x70
kimage_file_post_load_cleanup+0x5e/0xb0
SyS_kexec_file_load+0x448/0x680
? putname+0x54/0x60
? do_sys_open+0x190/0x1f0
entry_SYSCALL_64_fastpath+0x13/0x8f
---[ end trace 158bb74f5950ca2b ]---Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree
won't try to free a NULL pointer.Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.com
Signed-off-by: Thiago Jung Bauermann
Acked-by: Baoquan He
Cc: "Eric W. Biederman"
Cc: Vivek Goyal
Cc: Dave Young
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
24 May, 2016
1 commit
-
For the cases that some kernel (module) path stamps the crash reserved
memory(already mapped by the kernel) where has been loaded the second
kernel data, the kdump kernel will probably fail to boot when panic
happens (or even not happens) leaving the culprit at large, this is
unacceptable.The patch introduces a mechanism for detecting such cases:
1) After each crash kexec loading, it simply marks the reserved memory
regions readonly since we no longer access it after that. When someone
stamps the region, the first kernel will panic and trigger the kdump.
The weak arch_kexec_protect_crashkres() is introduced to do the actual
protection.2) To allow multiple loading, once 1) was done we also need to remark
the reserved memory to readwrite each time a system call related to
kdump is made. The weak arch_kexec_unprotect_crashkres() is introduced
to do the actual protection.The architecture can make its specific implementation by overriding
arch_kexec_protect_crashkres() and arch_kexec_unprotect_crashkres().Signed-off-by: Xunlei Pang
Cc: Eric Biederman
Cc: Dave Young
Cc: Minfei Huang
Cc: Vivek Goyal
Cc: Baoquan He
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
18 Mar, 2016
1 commit
-
Pull security layer updates from James Morris:
"There are a bunch of fixes to the TPM, IMA, and Keys code, with minor
fixes scattered across the subsystem.IMA now requires signed policy, and that policy is also now measured
and appraised"* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (67 commits)
X.509: Make algo identifiers text instead of enum
akcipher: Move the RSA DER encoding check to the crypto layer
crypto: Add hash param to pkcs1pad
sign-file: fix build with CMS support disabled
MAINTAINERS: update tpmdd urls
MODSIGN: linux/string.h should be #included to get memcpy()
certs: Fix misaligned data in extra certificate list
X.509: Handle midnight alternative notation in GeneralizedTime
X.509: Support leap seconds
Handle ISO 8601 leap seconds and encodings of midnight in mktime64()
X.509: Fix leap year handling again
PKCS#7: fix unitialized boolean 'want'
firmware: change kernel read fail to dev_dbg()
KEYS: Use the symbol value for list size, updated by scripts/insert-sys-cert
KEYS: Reserve an extra certificate symbol for inserting without recompiling
modsign: hide openssl output in silent builds
tpm_tis: fix build warning with tpm_tis_resume
ima: require signed IMA policy
ima: measure and appraise the IMA policy itself
ima: load policy using path
...
21 Feb, 2016
1 commit
-
Replace copy_file_from_fd() with kernel_read_file_from_fd().
Two new identifiers named READING_KEXEC_IMAGE and READING_KEXEC_INITRAMFS
are defined for measuring, appraising or auditing the kexec image and
initramfs.Changelog v3:
- return -EBADF, not -ENOEXEC
- identifier change
- split patch, moving copy_file_from_fd() to a separate patch
- split patch, moving IMA changes to a separate patch
v0:
- use kstat file size type loff_t, not size_t
- Calculate the file hash from the in memory buffer - Dave YoungSigned-off-by: Mimi Zohar
Acked-by: Kees Cook
Acked-by: Luis R. Rodriguez
Cc: Eric Biederman
Acked-by: Dave Young
30 Jan, 2016
2 commits
-
Change the callers of walk_iomem_res() scanning for the
following resources by name to use walk_iomem_res_desc()
instead."ACPI Tables"
"ACPI Non-volatile Storage"
"Persistent Memory (legacy)"
"Crash kernel"Note, the caller of walk_iomem_res() with "GART" will be removed
in a later patch.Signed-off-by: Toshi Kani
Signed-off-by: Borislav Petkov
Reviewed-by: Dave Young
Cc: Andrew Morton
Cc: Andy Lutomirski
Cc: Andy Lutomirski
Cc: Borislav Petkov
Cc: Brian Gerst
Cc: Chun-Yi
Cc: Dan Williams
Cc: Denys Vlasenko
Cc: Don Zickus
Cc: H. Peter Anvin
Cc: Lee, Chun-Yi
Cc: Linus Torvalds
Cc: Luis R. Rodriguez
Cc: Minfei Huang
Cc: Peter Zijlstra (Intel)
Cc: Ross Zwisler
Cc: Stephen Rothwell
Cc: Takao Indoh
Cc: Thomas Gleixner
Cc: Toshi Kani
Cc: kexec@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mm
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1453841853-11383-15-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar -
Set proper ioresource flags and types for crash kernel
reservation areas.Signed-off-by: Toshi Kani
Signed-off-by: Borislav Petkov
Reviewed-by: Dave Young
Cc: Andrew Morton
Cc: Andy Lutomirski
Cc: Baoquan He
Cc: Borislav Petkov
Cc: Brian Gerst
Cc: Denys Vlasenko
Cc: H. Peter Anvin
Cc: HATAYAMA Daisuke
Cc: Linus Torvalds
Cc: Luis R. Rodriguez
Cc: Minfei Huang
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Toshi Kani
Cc: Vivek Goyal
Cc: kexec@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mm
Link: http://lkml.kernel.org/r/1453841853-11383-8-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar
21 Jan, 2016
1 commit
-
Move the stuff currently only used by the kexec file code within
CONFIG_KEXEC_FILE (and CONFIG_KEXEC_VERIFY_SIG).Also move internal "struct kexec_sha_region" and "struct kexec_buf" into
"kexec_internal.h".Signed-off-by: Xunlei Pang
Cc: "Eric W. Biederman"
Cc: Dave Young
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Nov, 2015
1 commit
-
kexec output message misses the prefix "kexec", when Dave Young split the
kexec code. Now, we use file name as the output message prefix.Currently, the format of output message:
[ 140.290795] SYSC_kexec_load: hello, world
[ 140.291534] kexec: sanity_check_segment_list: hello, worldIdeally, the format of output message:
[ 30.791503] kexec: SYSC_kexec_load, Hello, world
[ 79.182752] kexec_core: sanity_check_segment_list, Hello, worldRemove the custom prefix "kexec" in output message.
Signed-off-by: Minfei Huang
Acked-by: Dave Young
Cc: "Eric W. Biederman"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
11 Sep, 2015
1 commit
-
Split kexec_file syscall related code to another file kernel/kexec_file.c
so that the #ifdef CONFIG_KEXEC_FILE in kexec.c can be dropped.Sharing variables and functions are moved to kernel/kexec_internal.h per
suggestion from Vivek and Petr.[akpm@linux-foundation.org: fix bisectability]
[akpm@linux-foundation.org: declare the various arch_kexec functions]
[akpm@linux-foundation.org: fix build]
Signed-off-by: Dave Young
Cc: Eric W. Biederman
Cc: Vivek Goyal
Cc: Petr Tesarik
Cc: Theodore Ts'o
Cc: Josh Boyer
Cc: David Howells
Cc: Geert Uytterhoeven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
