linux.git/tools/objtool, branch v6.19.12 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git objtool/klp: fix mkstemp() failure with long paths 2026-04-11T12:29:21+00:00 Joe Lawrence joe.lawrence@redhat.com 2026-03-10T20:37:41+00:00 3362980d8e02aa6e7d35fc7b2322fa8d84f7c25c [ Upstream commit 28e367a969b0c54c87ca655ec180715fe469fd14 ] The elf_create_file() function fails with EINVAL when the build directory path is long enough to truncate the "XXXXXX" suffix in the 256-byte tmp_name buffer. Simplify the code to remove the unnecessary dirname()/basename() split and concatenation. Instead, allocate the exact number of bytes needed for the path. Acked-by: Song Liu <song@kernel.org> Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> Link: https://patch.msgid.link/20260310203751.1479229-3-joe.lawrence@redhat.com Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 28e367a969b0c54c87ca655ec180715fe469fd14 ]

The elf_create_file() function fails with EINVAL when the build directory
path is long enough to truncate the "XXXXXX" suffix in the 256-byte
tmp_name buffer.

Simplify the code to remove the unnecessary dirname()/basename() split
and concatenation.  Instead, allocate the exact number of bytes needed for
the path.

Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/20260310203751.1479229-3-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
objtool: Fix Clang jump table detection 2026-04-11T12:29:21+00:00 Josh Poimboeuf jpoimboe@kernel.org 2026-03-09T16:03:05+00:00 9f201c9722a9517d1b5d1242c2e3735b5aa924f6 [ Upstream commit 4e5019216402ad0b4a84cff457b662d26803f103 ] With Clang, there can be a conditional forward jump between the load of the jump table address and the indirect branch. Fixes the following warning: vmlinux.o: warning: objtool: ___bpf_prog_run+0x1c5: sibling call from callable instruction with modified stack frame Reported-by: Arnd Bergmann <arnd@arndb.de> Closes: https://lore.kernel.org/a426d669-58bb-4be1-9eaa-6f3d83109e2d@app.fastmail.com Link: https://patch.msgid.link/7d8600caed08901b6679767488acd639f6df9688.1773071992.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 4e5019216402ad0b4a84cff457b662d26803f103 ]

With Clang, there can be a conditional forward jump between the load of
the jump table address and the indirect branch.

Fixes the following warning:

  vmlinux.o: warning: objtool: ___bpf_prog_run+0x1c5: sibling call from callable instruction with modified stack frame

Reported-by: Arnd Bergmann <arnd@arndb.de>
Closes: https://lore.kernel.org/a426d669-58bb-4be1-9eaa-6f3d83109e2d@app.fastmail.com
Link: https://patch.msgid.link/7d8600caed08901b6679767488acd639f6df9688.1773071992.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
objtool: Handle Clang RSP musical chairs 2026-04-02T11:25:21+00:00 Josh Poimboeuf jpoimboe@kernel.org 2026-03-06T17:35:06+00:00 0702339ec6f10849408deb29660a1f5389cf8cbd [ Upstream commit 7fdaa640c810cb42090a182c33f905bcc47a616a ] For no apparent reason (possibly related to CONFIG_KMSAN), Clang can randomly pass the value of RSP to other registers and then back again to RSP. Handle that accordingly. Fixes the following warnings: drivers/input/misc/uinput.o: warning: objtool: uinput_str_to_user+0x165: undefined stack state drivers/input/misc/uinput.o: warning: objtool: uinput_str_to_user+0x165: unknown CFA base reg -1 Reported-by: Arnd Bergmann <arnd@arndb.de> Closes: https://lore.kernel.org/90956545-2066-46e3-b547-10c884582eb0@app.fastmail.com Link: https://patch.msgid.link/240e6a172cc73292499334a3724d02ccb3247fc7.1772818491.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7fdaa640c810cb42090a182c33f905bcc47a616a ]

For no apparent reason (possibly related to CONFIG_KMSAN), Clang can
randomly pass the value of RSP to other registers and then back again to
RSP.  Handle that accordingly.

Fixes the following warnings:

  drivers/input/misc/uinput.o: warning: objtool: uinput_str_to_user+0x165: undefined stack state
  drivers/input/misc/uinput.o: warning: objtool: uinput_str_to_user+0x165: unknown CFA base reg -1

Reported-by: Arnd Bergmann <arnd@arndb.de>
Closes: https://lore.kernel.org/90956545-2066-46e3-b547-10c884582eb0@app.fastmail.com
Link: https://patch.msgid.link/240e6a172cc73292499334a3724d02ccb3247fc7.1772818491.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
objtool/klp: Disable unsupported pr_debug() usage 2026-04-02T11:25:21+00:00 Josh Poimboeuf jpoimboe@kernel.org 2026-02-10T21:50:10+00:00 b078f3c67137b8ffb91c65c9ebff04d348757161 [ Upstream commit e476bb277cf91b7ac3ea803ec78a4f0791bddec3 ] Instead of erroring out on unsupported pr_debug() (e.g., when patching a module), issue a warning and make it inert, similar to how unsupported tracepoints are currently handled. Reviewed-and-tested-by: Song Liu <song@kernel.org> Link: https://patch.msgid.link/3a7db3a5b7d4abf9b2534803a74e2e7231322738.1770759954.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e476bb277cf91b7ac3ea803ec78a4f0791bddec3 ]

Instead of erroring out on unsupported pr_debug() (e.g., when patching a
module), issue a warning and make it inert, similar to how unsupported
tracepoints are currently handled.

Reviewed-and-tested-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/3a7db3a5b7d4abf9b2534803a74e2e7231322738.1770759954.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
objtool: Use HOSTCFLAGS for HAVE_XXHASH test 2026-04-02T11:25:20+00:00 HONG Yifan elsk@google.com 2026-03-03T01:03:39+00:00 1786b6847e9061875f26a6124e1ca6e2d91fdd66 [ Upstream commit 32234049107d012703d50547e815f198f147968b ] Previously, HAVE_XXHASH is tested by invoking HOSTCC without HOSTCFLAGS. Consider the following scenario: - The host machine has libxxhash installed - We build the kernel with HOSTCFLAGS containing a --sysroot that does not have xxhash.h (for hermetic builds) In this case, HAVE_XXHASH is set to y, but when it builds objtool with HOSTCFLAGS, because the --sysroot does not contain xxhash.h, the following error is raised: <...>/common/tools/objtool/include/objtool/checksum_types.h:12:10: fatal error: 'xxhash.h' file not found 12 | #include <xxhash.h> | ^~~~~~~~~~ To resolve the error, we test HAVE_XXHASH by invoking HOSTCC with HOSTCFLAGS. Signed-off-by: HONG Yifan <elsk@google.com> Reviewed-by: Carlos Llamas <cmllamas@google.com> Link: https://patch.msgid.link/20260303010340.306164-1-elsk@google.com Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 32234049107d012703d50547e815f198f147968b ]

Previously, HAVE_XXHASH is tested by invoking HOSTCC without HOSTCFLAGS.

Consider the following scenario:

- The host machine has libxxhash installed
- We build the kernel with HOSTCFLAGS containing a --sysroot that does
  not have xxhash.h (for hermetic builds)

In this case, HAVE_XXHASH is set to y, but when it builds objtool with
HOSTCFLAGS, because the --sysroot does not contain xxhash.h, the
following error is raised:

<...>/common/tools/objtool/include/objtool/checksum_types.h:12:10: fatal error: 'xxhash.h' file not found
   12 | #include <xxhash.h>
      |          ^~~~~~~~~~

To resolve the error, we test HAVE_XXHASH by invoking HOSTCC with
HOSTCFLAGS.

Signed-off-by: HONG Yifan <elsk@google.com>
Reviewed-by: Carlos Llamas <cmllamas@google.com>
Link: https://patch.msgid.link/20260303010340.306164-1-elsk@google.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
objtool/klp: fix data alignment in __clone_symbol() 2026-04-02T11:25:13+00:00 Joe Lawrence joe.lawrence@redhat.com 2026-03-10T20:37:40+00:00 06164b31605429f3b1d820c93a3c0450980e3d4e [ Upstream commit 2f2600decb3004938762a3f2d0eba3ea9e01045b ] Commit 356e4b2f5b80 ("objtool: Fix data alignment in elf_add_data()") corrected the alignment of data within a section (honoring the section's sh_addralign). Apply the same alignment when klp-diff mode clones a symbol, adjusting the new symbol's offset for the output section's sh_addralign. Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files") Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> Link: https://patch.msgid.link/20260310203751.1479229-2-joe.lawrence@redhat.com Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2f2600decb3004938762a3f2d0eba3ea9e01045b ]

Commit 356e4b2f5b80 ("objtool: Fix data alignment in elf_add_data()")
corrected the alignment of data within a section (honoring the section's
sh_addralign).  Apply the same alignment when klp-diff mode clones a
symbol, adjusting the new symbol's offset for the output section's
sh_addralign.

Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/20260310203751.1479229-2-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
objtool: Fix another stack overflow in validate_branch() 2026-03-19T15:15:07+00:00 Josh Poimboeuf jpoimboe@kernel.org 2026-03-06T18:28:14+00:00 6cf3e0c4cd2f430e66dcbc97cfb9ecfa615936f7 [ Upstream commit 9a73f085dc91980ab7fcc5e9716f4449424b3b59 ] The insn state is getting saved on the stack twice for each recursive iteration. No need for that, once is enough. Fixes the following reported stack overflow: drivers/scsi/qla2xxx/qla_dbg.o: error: SIGSEGV: objtool stack overflow! Segmentation fault Fixes: 70589843b36f ("objtool: Add option to trace function validation") Reported-by: Arnd Bergmann <arnd@arndb.de> Closes: https://lore.kernel.org/90956545-2066-46e3-b547-10c884582eb0@app.fastmail.com Link: https://patch.msgid.link/8b97f62d083457f3b0a29a424275f7957dd3372f.1772821683.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 9a73f085dc91980ab7fcc5e9716f4449424b3b59 ]

The insn state is getting saved on the stack twice for each recursive
iteration.  No need for that, once is enough.

Fixes the following reported stack overflow:

  drivers/scsi/qla2xxx/qla_dbg.o: error: SIGSEGV: objtool stack overflow!
  Segmentation fault

Fixes: 70589843b36f ("objtool: Add option to trace function validation")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Closes: https://lore.kernel.org/90956545-2066-46e3-b547-10c884582eb0@app.fastmail.com
Link: https://patch.msgid.link/8b97f62d083457f3b0a29a424275f7957dd3372f.1772821683.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
objtool: Fix data alignment in elf_add_data() 2026-03-19T15:15:07+00:00 Josh Poimboeuf jpoimboe@kernel.org 2026-03-05T03:31:20+00:00 fa31c5b01bb47f155a5e9ecbe8dc9672032b60c8 [ Upstream commit 356e4b2f5b80f757965f3f4d0219c81fca91b6f2 ] Any data added to a section needs to be aligned in accordance with the section's sh_addralign value. Particularly strings added to a .str1.8 section. Otherwise you may get some funky strings. Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files") Link: https://patch.msgid.link/d962fc0ca24fa0825cca8dad71932dccdd9312a9.1772681234.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 356e4b2f5b80f757965f3f4d0219c81fca91b6f2 ]

Any data added to a section needs to be aligned in accordance with the
section's sh_addralign value.  Particularly strings added to a .str1.8
section.  Otherwise you may get some funky strings.

Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Link: https://patch.msgid.link/d962fc0ca24fa0825cca8dad71932dccdd9312a9.1772681234.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
objtool/klp: Fix detection of corrupt static branch/call entries 2026-03-19T15:15:07+00:00 Josh Poimboeuf jpoimboe@kernel.org 2026-02-10T21:50:09+00:00 0a701ede2dfffbbd16f65fb3e3f3aff31e3dbaf0 [ Upstream commit f9fb44b0ecefc1f218db56661ed66d4e8d67317d ] Patching a function which references a static key living in a kernel module is unsupported due to ordering issues inherent to late module patching: 1) Load a livepatch module which has a __jump_table entry which needs a klp reloc to reference static key K which lives in module M. 2) The __jump_table klp reloc does *not* get resolved because module M is not yet loaded. 3) jump_label_add_module() corrupts memory (or causes a panic) when dereferencing the uninitialized pointer to key K. validate_special_section_klp_reloc() intends to prevent that from ever happening by catching it at build time. However, it incorrectly assumes the special section entry's reloc symbol references have already been converted from section symbols to object symbols, causing the validation to miss corruption in extracted static branch/call table entries. Make sure the references have been properly converted before doing the validation. Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files") Reported-by: Song Liu <song@kernel.org> Reviewed-and-tested-by: Song Liu <song@kernel.org> Link: https://patch.msgid.link/124ad747b751df0df1725eff89de8332e3fb26d6.1770759954.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f9fb44b0ecefc1f218db56661ed66d4e8d67317d ]

Patching a function which references a static key living in a kernel
module is unsupported due to ordering issues inherent to late module
patching:

  1) Load a livepatch module which has a __jump_table entry which needs
     a klp reloc to reference static key K which lives in module M.

  2) The __jump_table klp reloc does *not* get resolved because module M
     is not yet loaded.

  3) jump_label_add_module() corrupts memory (or causes a panic) when
     dereferencing the uninitialized pointer to key K.

validate_special_section_klp_reloc() intends to prevent that from ever
happening by catching it at build time.  However, it incorrectly assumes
the special section entry's reloc symbol references have already been
converted from section symbols to object symbols, causing the validation
to miss corruption in extracted static branch/call table entries.

Make sure the references have been properly converted before doing the
validation.

Fixes: dd590d4d57eb ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Reported-by: Song Liu <song@kernel.org>
Reviewed-and-tested-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/124ad747b751df0df1725eff89de8332e3fb26d6.1770759954.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
kbuild: Leave objtool binary around with 'make clean' 2026-03-12T11:09:39+00:00 Nathan Chancellor nathan@kernel.org 2026-02-28T05:40:48+00:00 bc9cf84c9311aab5bc1da2985385864ccda25f3b commit fdb12c8a24a453bdd6759979b6ef1e04ebd4beb4 upstream. The difference between 'make clean' and 'make mrproper' is documented in 'make help' as: clean - Remove most generated files but keep the config and enough build support to build external modules mrproper - Remove all generated files + config + various backup files After commit 68b4fe32d737 ("kbuild: Add objtool to top-level clean target"), running 'make clean' then attempting to build an external module with the resulting build directory fails with $ make ARCH=x86_64 O=build clean $ make -C build M=... MO=... ... /bin/sh: line 1: .../build/tools/objtool/objtool: No such file or directory as 'make clean' removes the objtool binary. Split the objtool clean target into mrproper and clean like Kbuild does and remove all generated artifacts with 'make clean' except for the objtool binary, which is removed with 'make mrproper'. To avoid a small race when running the objtool clean target through both objtool_mrproper and objtool_clean when running 'make mrproper', modify objtool's clean up find command to avoid using find's '-delete' command by piping the files into 'xargs rm -f' like the rest of Kbuild does. Cc: stable@vger.kernel.org Fixes: 68b4fe32d737 ("kbuild: Add objtool to top-level clean target") Reported-by: Michal Suchanek <msuchanek@suse.de> Closes: https://lore.kernel.org/20260225112633.6123-1-msuchanek@suse.de/ Reported-by: Rainer Fiebig <jrf@mailbox.org> Closes: https://lore.kernel.org/62d12399-76e5-3d40-126a-7490b4795b17@mailbox.org/ Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Nicolas Schier <nsc@kernel.org> Tested-by: Nicolas Schier <nsc@kernel.org> Link: https://patch.msgid.link/20260227-avoid-objtool-binary-removal-clean-v1-1-122f3e55eae9@kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fdb12c8a24a453bdd6759979b6ef1e04ebd4beb4 upstream.

The difference between 'make clean' and 'make mrproper' is documented in
'make help' as:

  clean     - Remove most generated files but keep the config and
              enough build support to build external modules
  mrproper  - Remove all generated files + config + various backup files

After commit 68b4fe32d737 ("kbuild: Add objtool to top-level clean
target"), running 'make clean' then attempting to build an external
module with the resulting build directory fails with

  $ make ARCH=x86_64 O=build clean

  $ make -C build M=... MO=...
  ...
  /bin/sh: line 1: .../build/tools/objtool/objtool: No such file or directory

as 'make clean' removes the objtool binary.

Split the objtool clean target into mrproper and clean like Kbuild does
and remove all generated artifacts with 'make clean' except for the
objtool binary, which is removed with 'make mrproper'. To avoid a small
race when running the objtool clean target through both objtool_mrproper
and objtool_clean when running 'make mrproper', modify objtool's clean
up find command to avoid using find's '-delete' command by piping the
files into 'xargs rm -f' like the rest of Kbuild does.

Cc: stable@vger.kernel.org
Fixes: 68b4fe32d737 ("kbuild: Add objtool to top-level clean target")
Reported-by: Michal Suchanek <msuchanek@suse.de>
Closes: https://lore.kernel.org/20260225112633.6123-1-msuchanek@suse.de/
Reported-by: Rainer Fiebig <jrf@mailbox.org>
Closes: https://lore.kernel.org/62d12399-76e5-3d40-126a-7490b4795b17@mailbox.org/
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Tested-by: Nicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/20260227-avoid-objtool-binary-removal-clean-v1-1-122f3e55eae9@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>