x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes section")

... only started ignoring the .notes sections in print_absolute_relocs(),
but the same logic should also by applied in walk_relocs() to avoid
such relocations.

[ mingo: Fixed various typos in the changelog, removed extra curly braces from the code. ]

Fixes: aaa8736370db ("x86, relocs: Ignore relocations in .notes section")
Fixes: 5ead97c84fa7 ("xen: Core Xen implementation")
Fixes: da1a679cde9b ("Add /sys/kernel/notes")
Signed-off-by: Guixiong Wei <weiguixiong@bytedance.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240317150547.24910-1-weiguixiong@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes section")

... only started ignoring the .notes sections in print_absolute_relocs(),
but the same logic should also by applied in walk_relocs() to avoid
such relocations.

[ mingo: Fixed various typos in the changelog, removed extra curly braces from the code. ]

Fixes: aaa8736370db ("x86, relocs: Ignore relocations in .notes section")
Fixes: 5ead97c84fa7 ("xen: Core Xen implementation")
Fixes: da1a679cde9b ("Add /sys/kernel/notes")
Signed-off-by: Guixiong Wei <weiguixiong@bytedance.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240317150547.24910-1-weiguixiong@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes section")

... only started ignoring the .notes sections in print_absolute_relocs(),
but the same logic should also by applied in walk_relocs() to avoid
such relocations.

[ mingo: Fixed various typos in the changelog, removed extra curly braces from the code. ]

Fixes: aaa8736370db ("x86, relocs: Ignore relocations in .notes section")
Fixes: 5ead97c84fa7 ("xen: Core Xen implementation")
Fixes: da1a679cde9b ("Add /sys/kernel/notes")
Signed-off-by: Guixiong Wei <weiguixiong@bytedance.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240317150547.24910-1-weiguixiong@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes section")

... only started ignoring the .notes sections in print_absolute_relocs(),
but the same logic should also by applied in walk_relocs() to avoid
such relocations.

[ mingo: Fixed various typos in the changelog, removed extra curly braces from the code. ]

Fixes: aaa8736370db ("x86, relocs: Ignore relocations in .notes section")
Fixes: 5ead97c84fa7 ("xen: Core Xen implementation")
Fixes: da1a679cde9b ("Add /sys/kernel/notes")
Signed-off-by: Guixiong Wei <weiguixiong@bytedance.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240317150547.24910-1-weiguixiong@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes section")

... only started ignoring the .notes sections in print_absolute_relocs(),
but the same logic should also by applied in walk_relocs() to avoid
such relocations.

[ mingo: Fixed various typos in the changelog, removed extra curly braces from the code. ]

Fixes: aaa8736370db ("x86, relocs: Ignore relocations in .notes section")
Fixes: 5ead97c84fa7 ("xen: Core Xen implementation")
Fixes: da1a679cde9b ("Add /sys/kernel/notes")
Signed-off-by: Guixiong Wei <weiguixiong@bytedance.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240317150547.24910-1-weiguixiong@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes section")

... only started ignoring the .notes sections in print_absolute_relocs(),
but the same logic should also by applied in walk_relocs() to avoid
such relocations.

[ mingo: Fixed various typos in the changelog, removed extra curly braces from the code. ]

Fixes: aaa8736370db ("x86, relocs: Ignore relocations in .notes section")
Fixes: 5ead97c84fa7 ("xen: Core Xen implementation")
Fixes: da1a679cde9b ("Add /sys/kernel/notes")
Signed-off-by: Guixiong Wei <weiguixiong@bytedance.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240317150547.24910-1-weiguixiong@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes

x86/boot: Ignore relocations in .notes sections in walk_relocs() too

[ Upstream commit 76e9762d66373354b45c33b60e9a53ef2a3c5ff2 ]

Commit:

aaa8736370db ("x86, relocs: Ignore relocations in .notes section")

... only started ignoring the .notes sections in print_absolute_relocs(),
but the same logic should also by applied in walk_relocs() to avoid
such relocations.

[ mingo: Fixed various typos in the changelog, removed extra curly braces from the code. ]

Fixes: aaa8736370db ("x86, relocs: Ignore relocations in .notes section")
Fixes: 5ead97c84fa7 ("xen: Core Xen implementation")
Fixes: da1a679cde9b ("Add /sys/kernel/notes")
Signed-off-by: Guixiong Wei <weiguixiong@bytedance.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240317150547.24910-1-weiguixiong@bytedance.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

x86, relocs: Ignore relocations in .notes section

[ Upstream commit aaa8736370db1a78f0e8434344a484f9fd20be3b ]

When building with CONFIG_XEN_PV=y, .text symbols are emitted into
the .notes section

x86, relocs: Ignore relocations in .notes section

[ Upstream commit aaa8736370db1a78f0e8434344a484f9fd20be3b ]

When building with CONFIG_XEN_PV=y, .text symbols are emitted into
the .notes section so that Xen can find the "startup_xen" entry point.
This information is used prior to booting the kernel, so relocations
are not useful. In fact, performing relocations against the .notes
section means that the KASLR base is exposed since /sys/kernel/notes
is world-readable.

To avoid leaking the KASLR base without breaking unprivileged tools that
are expecting to read /sys/kernel/notes, skip performing relocations in
the .notes section. The values readable in .notes are then identical to
those found in System.map.

Reported-by: Guixiong Wei <guixiongwei@gmail.com>
Closes: https://lore.kernel.org/all/20240218073501.54555-1-guixiongwei@gmail.com/
Fixes: 5ead97c84fa7 ("xen: Core Xen implementation")
Fixes: da1a679cde9b ("Add /sys/kernel/notes")
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

ELF: fix all "Elf" typos

ELF is acronym and therefore should be spelled in all caps.

I left one exception at Documentation/arm/nwfpe/nwfpe.rst which looks like
being written in the first person.

L

ELF: fix all "Elf" typos

ELF is acronym and therefore should be spelled in all caps.

I left one exception at Documentation/arm/nwfpe/nwfpe.rst which looks like
being written in the first person.

Link: https://lkml.kernel.org/r/Y/3wGWQviIOkyLJW@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

x86/tools/relocs: Ignore __kcfi_typeid_ relocations

The compiler generates __kcfi_typeid_ symbols for annotating assembly
functions with type information. These are constants that can be
referenced

x86/tools/relocs: Ignore __kcfi_typeid_ relocations

The compiler generates __kcfi_typeid_ symbols for annotating assembly
functions with type information. These are constants that can be
referenced in assembly code and are resolved by the linker. Ignore
them in relocs.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220908215504.3686827-20-samitolvanen@google.com

show more ...

x86/build: Use the proper name CONFIG_FW_LOADER

Commit in Fixes intends to add the expression regex only when FW_LOADER
is enabled - not FW_LOADER_BUILTIN. Latter is a leftover from a previous
patch

x86/build: Use the proper name CONFIG_FW_LOADER

Commit in Fixes intends to add the expression regex only when FW_LOADER
is enabled - not FW_LOADER_BUILTIN. Latter is a leftover from a previous
patchset and not a valid config item.

So, adjust the condition to the actual name of the config.

[ bp: Cleanup commit message. ]

Fixes: c8dcf655ec81 ("x86/build: Tuck away built-in firmware under FW_LOADER")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20211229111553.5846-1-lukas.bulwahn@gmail.com

show more ...

x86/tools/relocs: Support >64K section headers

While the relocs tool already supports finding the total number of
section headers if vmlinux exceeds 64K sections, it fails to read the
extended symbo

x86/tools/relocs: Support >64K section headers

While the relocs tool already supports finding the total number of
section headers if vmlinux exceeds 64K sections, it fails to read the
extended symbol table to get section header indexes for symbols, causing
incorrect symbol table indexes to be used when there are > 64K symbols.

Parse the ELF file to read the extended symbol table info, and then
replace all direct references to st_shndx with calls to sym_index(),
which will determine whether the value can be read directly or whether
the value should be pulled out of the extended table.

This is needed for future FGKASLR support, which uses a separate section
per function.

Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20211013175742.1197608-2-keescook@chromium.org

show more ...

x86/build: Tuck away built-in firmware under FW_LOADER

When FW_LOADER is modular or disabled we don't use it.
Update x86 relocs to reflect that.

Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off

x86/build: Tuck away built-in firmware under FW_LOADER

When FW_LOADER is modular or disabled we don't use it.
Update x86 relocs to reflect that.

Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20211021155843.1969401-7-mcgrof@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

x86/tools/relocs: Mark die() with the printf function attr format

Mark die() as a function which accepts printf-style arguments so that
the compiler can typecheck them against the supplied format st

x86/tools/relocs: Mark die() with the printf function attr format

Mark die() as a function which accepts printf-style arguments so that
the compiler can typecheck them against the supplied format string.

Use the C99 inttypes.h format specifiers as relocs.c gets built for both
32- and 64-bit.

Original version of the patch by Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: http://lkml.kernel.org/r/YNnb6Q4QHtNYC049@zn.tnic

show more ...

x86/tools/relocs: Fix non-POSIX regexp

Trying to run a cross-compiled x86 relocs tool on a BSD based
HOSTCC leads to errors like

VOFFSET arch/x86/boot/compressed/../voffset.h - due to: vmlinux

x86/tools/relocs: Fix non-POSIX regexp

Trying to run a cross-compiled x86 relocs tool on a BSD based
HOSTCC leads to errors like

VOFFSET arch/x86/boot/compressed/../voffset.h - due to: vmlinux
CC arch/x86/boot/compressed/misc.o - due to: arch/x86/boot/compressed/../voffset.h
OBJCOPY arch/x86/boot/compressed/vmlinux.bin - due to: vmlinux
RELOCS arch/x86/boot/compressed/vmlinux.relocs - due to: vmlinux
empty (sub)expressionarch/x86/boot/compressed/Makefile:118: recipe for target 'arch/x86/boot/compressed/vmlinux.relocs' failed
make[3]: *** [arch/x86/boot/compressed/vmlinux.relocs] Error 1

It turns out that relocs.c uses patterns like

"something(|_end)"

This is not valid syntax or gives undefined results according
to POSIX 9.5.3 ERE Grammar

https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html

It seems to be silently accepted by the Linux regexp() implementation
while a BSD host complains.

Such patterns can be replaced by a transformation like

"(|p1|p2)" -> "(p1|p2)?"

Fixes: fd952815307f ("x86-32, relocs: Whitelist more symbols for ld bug workaround")
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

show more ...

module: remove EXPORT_UNUSED_SYMBOL*

EXPORT_UNUSED_SYMBOL* is not actually used anywhere. Remove the
unused functionality as we generally just remove unused code anyway.

Reviewed-by: Miroslav Bene

module: remove EXPORT_UNUSED_SYMBOL*

EXPORT_UNUSED_SYMBOL* is not actually used anywhere. Remove the
unused functionality as we generally just remove unused code anyway.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>

show more ...

module: remove EXPORT_SYMBOL_GPL_FUTURE

As far as I can tell this has never been used at all, and certainly
not any time recently.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Vel

module: remove EXPORT_SYMBOL_GPL_FUTURE

As far as I can tell this has never been used at all, and certainly
not any time recently.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>

show more ...

x86/build: Treat R_386_PLT32 relocation as R_386_PC32

This is similar to commit

b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32")

but for i386. As far as the kernel is concerned, R_386

x86/build: Treat R_386_PLT32 relocation as R_386_PC32

This is similar to commit

b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32")

but for i386. As far as the kernel is concerned, R_386_PLT32 can be
treated the same as R_386_PC32.

R_386_PLT32/R_X86_64_PLT32 are PC-relative relocation types which
can only be used by branches. If the referenced symbol is defined
externally, a PLT will be used.

R_386_PC32/R_X86_64_PC32 are PC-relative relocation types which can be
used by address taking operations and branches. If the referenced symbol
is defined externally, a copy relocation/canonical PLT entry will be
created in the executable.

On x86-64, there is no PIC vs non-PIC PLT distinction and an
R_X86_64_PLT32 relocation is produced for both `call/jmp foo` and
`call/jmp foo@PLT` with newer (2018) GNU as/LLVM integrated assembler.
This avoids canonical PLT entries (st_shndx=0, st_value!=0).

On i386, there are 2 types of PLTs, PIC and non-PIC. Currently,
the GCC/GNU as convention is to use R_386_PC32 for non-PIC PLT and
R_386_PLT32 for PIC PLT. Copy relocations/canonical PLT entries
are possible ABI issues but GCC/GNU as will likely keep the status
quo because (1) the ABI is legacy (2) the change will drop a GNU
ld diagnostic for non-default visibility ifunc in shared objects.

clang-12 -fno-pic (since [1]) can emit R_386_PLT32 for compiler
generated function declarations, because preventing canonical PLT
entries is weighed over the rare ifunc diagnostic.

Further info for the more interested:

https://github.com/ClangBuiltLinux/linux/issues/1210
https://sourceware.org/bugzilla/show_bug.cgi?id=27169
https://github.com/llvm/llvm-project/commit/a084c0388e2a59b9556f2de0083333232da3f1d6 [1]

[ bp: Massage commit message. ]

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Link: https://lkml.kernel.org/r/20210127205600.1227437-1-maskray@google.com

show more ...

x86/build: Treat R_386_PLT32 relocation as R_386_PC32

commit bb73d07148c405c293e576b40af37737faf23a6a upstream.

This is similar to commit

b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC3

x86/build: Treat R_386_PLT32 relocation as R_386_PC32

commit bb73d07148c405c293e576b40af37737faf23a6a upstream.

This is similar to commit

b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32")

but for i386. As far as the kernel is concerned, R_386_PLT32 can be
treated the same as R_386_PC32.

R_386_PLT32/R_X86_64_PLT32 are PC-relative relocation types which
can only be used by branches. If the referenced symbol is defined
externally, a PLT will be used.

R_386_PC32/R_X86_64_PC32 are PC-relative relocation types which can be
used by address taking operations and branches. If the referenced symbol
is defined externally, a copy relocation/canonical PLT entry will be
created in the executable.

On x86-64, there is no PIC vs non-PIC PLT distinction and an
R_X86_64_PLT32 relocation is produced for both `call/jmp foo` and
`call/jmp foo@PLT` with newer (2018) GNU as/LLVM integrated assembler.
This avoids canonical PLT entries (st_shndx=0, st_value!=0).

On i386, there are 2 types of PLTs, PIC and non-PIC. Currently,
the GCC/GNU as convention is to use R_386_PC32 for non-PIC PLT and
R_386_PLT32 for PIC PLT. Copy relocations/canonical PLT entries
are possible ABI issues but GCC/GNU as will likely keep the status
quo because (1) the ABI is legacy (2) the change will drop a GNU
ld diagnostic for non-default visibility ifunc in shared objects.

clang-12 -fno-pic (since [1]) can emit R_386_PLT32 for compiler
generated function declarations, because preventing canonical PLT
entries is weighed over the rare ifunc diagnostic.

Further info for the more interested:

https://github.com/ClangBuiltLinux/linux/issues/1210
https://sourceware.org/bugzilla/show_bug.cgi?id=27169
https://github.com/llvm/llvm-project/commit/a084c0388e2a59b9556f2de0083333232da3f1d6 [1]

[ bp: Massage commit message. ]

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Link: https://lkml.kernel.org/r/20210127205600.1227437-1-maskray@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

x86/tools/relocs: Fix big section header tables

In case when the number of entries in the section header table is larger
then or equal to SHN_LORESERVE the size of the table is held in the sh_size
m

x86/tools/relocs: Fix big section header tables

In case when the number of entries in the section header table is larger
then or equal to SHN_LORESERVE the size of the table is held in the sh_size
member of the initial entry in section header table instead of e_shnum.
Same with the string table index which is located in sh_link instead of
e_shstrndx.

This case is easily reproducible with KCFLAGS="-ffunction-sections",
bzImage build fails with "String table index out of bounds" error.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Eric W . Biederman <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181129155615.2594-1-asavkov@redhat.com
[ Simplify the die() lines. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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x86/irq/64: Split the IRQ stack into its own pages

Currently, the IRQ stack is hardcoded as the first page of the percpu
area, and the stack canary lives on the IRQ stack. The former gets in
the way

x86/irq/64: Split the IRQ stack into its own pages

Currently, the IRQ stack is hardcoded as the first page of the percpu
area, and the stack canary lives on the IRQ stack. The former gets in
the way of adding an IRQ stack guard page, and the latter is a potential
weakness in the stack canary mechanism.

Split the IRQ stack into its own private percpu pages.

[ tglx: Make 64 and 32 bit share struct irq_stack ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Feng Tang <feng.tang@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jordan Borgner <mail@jordan-borgner.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Maran Wilson <maran.wilson@oracle.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: "Rafael Ávila de Espíndola" <rafael@espindo.la>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20190414160146.267376656@linutronix.de

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x86: Clean up 'sizeof x' => 'sizeof(x)'

"sizeof(x)" is the canonical coding style used in arch/x86 most of the time.
Fix the few places that didn't follow the convention.

(Also do some whitespace c

x86: Clean up 'sizeof x' => 'sizeof(x)'

"sizeof(x)" is the canonical coding style used in arch/x86 most of the time.
Fix the few places that didn't follow the convention.

(Also do some whitespace cleanups in a few places while at it.)

[ mingo: Rewrote the changelog. ]

Signed-off-by: Jordan Borgner <mail@jordan-borgner.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181028125828.7rgammkgzep2wpam@JordanDesktop
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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x86: Add support for 64-bit place relative relocations

Add support for R_X86_64_PC64 relocations, which operate on 64-bit
quantities holding a relative symbol reference. Also remove the
definition o

x86: Add support for 64-bit place relative relocations

Add support for R_X86_64_PC64 relocations, which operate on 64-bit
quantities holding a relative symbol reference. Also remove the
definition of R_X86_64_NUM: given that it is currently unused, it
is unclear what the new value should be.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jessica Yu <jeyu@kernel.org>
Link: https://lkml.kernel.org/r/20180919065144.25010-5-ard.biesheuvel@linaro.org

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x86/relocs: Add __end_rodata_aligned to S_REL

This new symbol needs to be in the workaround-list for buggy
binutils, otherwise the build with gcc-4.6 fails.

Fixes: 39d668e04eda ('x86/mm/pti: Make p

x86/relocs: Add __end_rodata_aligned to S_REL

This new symbol needs to be in the workaround-list for buggy
binutils, otherwise the build with gcc-4.6 fails.

Fixes: 39d668e04eda ('x86/mm/pti: Make pti_clone_kernel_text() compile on 32 bit')
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linux-Next Mailing List <linux-next@vger.kernel.org>
Link: https://lkml.kernel.org/r/20180809094449.ddmnrkz7qkvo3j2x@suse.de

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x86: Treat R_X86_64_PLT32 as R_X86_64_PC32

On i386, there are 2 types of PLTs, PIC and non-PIC. PIE and shared
objects must use PIC PLT. To use PIC PLT, you need to load
_GLOBAL_OFFSET_TABLE_ into

x86: Treat R_X86_64_PLT32 as R_X86_64_PC32

On i386, there are 2 types of PLTs, PIC and non-PIC. PIE and shared
objects must use PIC PLT. To use PIC PLT, you need to load
_GLOBAL_OFFSET_TABLE_ into EBX first. There is no need for that on
x86-64 since x86-64 uses PC-relative PLT.

On x86-64, for 32-bit PC-relative branches, we can generate PLT32
relocation, instead of PC32 relocation, which can also be used as
a marker for 32-bit PC-relative branches. Linker can always reduce
PLT32 relocation to PC32 if function is defined locally. Local
functions should use PC32 relocation. As far as Linux kernel is
concerned, R_X86_64_PLT32 can be treated the same as R_X86_64_PC32
since Linux kernel doesn't use PLT.

R_X86_64_PLT32 for 32-bit PC-relative branches has been enabled in
binutils master branch which will become binutils 2.31.

[ hjl is working on having better documentation on this all, but a few
more notes from him:

"PLT32 relocation is used as marker for PC-relative branches. Because
of EBX, it looks odd to generate PLT32 relocation on i386 when EBX
doesn't have GOT.

As for symbol resolution, PLT32 and PC32 relocations are almost
interchangeable. But when linker sees PLT32 relocation against a
protected symbol, it can resolved locally at link-time since it is
used on a branch instruction. Linker can't do that for PC32
relocation"

but for the kernel use, the two are basically the same, and this
commit gets things building and working with the current binutils
master - Linus ]

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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