| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.
Simplify this process by using the helper force_sig_fault. Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.
In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-hexagon@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.
Simplify this process by using the helper force_sig_fault. Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.
In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
Cc: linux-c6x-dev@linux-c6x.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.
Simplify this process by using the helper force_sig_fault. Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.
In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: linux-alpha@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Filling in struct siginfo before calling send_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.
Simplify this process by using the helper send_sig_fault. Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls send_sig_info.
In short about a 5 line reduction in code for every time send_sig_info
is called, which makes the calling function clearer.
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: linux-alpha@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Using an si_code of 0 that aliases with SI_USER is clearly the wrong
thing todo, and causes problems in interesting ways.
For use in unknown_exception the recently defined TRAP_UNK
semantically is a perfect fit. For use in RunModeException it looks
like something more specific than TRAP_UNK could be used. No one has
bothered to find a better fit than the broken si_code of 0 in all of
these years and I don't see an obvious better fit so TRAP_UNK is
switching RunModeException to return TRAP_UNK is clearly an
improvement.
Recent history suggests no actually cares about crazy corner
cases of the kernel behavior like this so I don't expect any
regressions from changing this. However if something does
happen this change is easy to revert.
Though I wonder if SIGKILL might not be a better fit.
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <kumar.gala@freescale.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx")
Fixes: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Using an si_code of 0 that aliases with SI_USER is clearly the wrong
thing to do, and causes problems in interesting ways.
For it really is not clear to me if using TRAP_UNK bugcheck or
the default case of gentrap is really the best way to handle
things. There is certainly enough information that that a more
specific si_code could potentially be used. That said TRAP_UNK
is definitely an improvement over 0 as it removes the ambiguiuty
of what si_code of 0 with SIGTRAP means on alpha.
Recent history suggests no actually cares about crazy corner cases of
the kernel behavior like this so I don't expect any regressions from
changing this. However if something does happen this change is easy
to revert.
Cc: Helge Deller <deller@gmx.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-alpha@vger.kernel.org
Fixes: 0a635c7a84cf ("Fill in siginfo_t.")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Both powerpc and alpha have cases where they wronly set si_code to 0
in combination with SIGTRAP and don't mean SI_USER.
About half the time this is because the architecture can not report
accurately what kind of trap exception triggered the trap exception.
The other half the time it looks like no one has bothered to
figure out an appropriate si_code.
For the cases where the architecture does not have enough information
or is too lazy to figure out exactly what kind of trap exception
it is define TRAP_UNK.
Cc: linux-api@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
The si_code of 0 (aka SI_USER) has fields si_pid and si_uid not
si_addr so it so only by luck would the appropriate fields by copied
to userspace by copy_siginfo_to_user.
This is just broken and wrong.
Make it obvious what is happening by moving the si_code from a
parameter of the one call to ucf64_raise_sigfpe to a constant value
that info.si_code gets set to.
Explicitly set the si_code to FPE_FLTUNK the newly reserved floating
point si_code for an unknown floating point exception.
It looks like there is a fair chance that this is a code path that has
never been used in real life on unicore32. The bad si_code and the
print statement that calls it an unhandled exception. So I really
don't expect anyone will mind if this just gets fixed.
In similar situations on more popular architectures the conclusion was
just fix it.
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Arnd Bergmann <arnd@arndb.de>
Fixes: d9bc15794d12 ("unicore32 additional architecture files: float point handling")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Using an si_code of 0 that aliases with SI_USER is clearly the
wrong thing todo, and causes problems in interesting ways.
The newly defined FPE_FLTUNK semantically appears to fit the
bill so use it instead.
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <kumar.gala@freescale.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx")
Fixes: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Using an si_code of 0 that aliases with SI_USER is clearly the wrong
thing todo, and causes problems in interesting ways.
The newly defined FPE_FLTUNK semantically appears to fit the bill so
use it instead.
Given recent experience in this area odds are it will not
break anything. Fixing it removes a hazard to kernel maintenance.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Fixes: 987159266c45 ("Linux version 2.3.48")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Using an si_code of 0 that aliases with SI_USER is clearly the wrong
thing todo, and causes problems in interesting ways.
The newly defined FPE_FLTUNK semantically appears to fit the bill so
use it instead.
Given recent experience in this area odds are it will not break
anything. Fixing it removes a hazard to kernel maintenance.
Cc: Helge Deller <deller@gmx.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-alpha@vger.kernel.org
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Fixes: 0a635c7a84cf ("Fill in siginfo_t.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
With the recent architecture cleanups these si_codes are always
defined so there is no need to test for them.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
After the last round of cleanups to siginfo.h SEGV_BNDERR is defined
on all architectures so testing to see if it is defined is unnecessary.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
After more experience with the cases where no one the si_code of 0
is used both as a signal specific si_code, and as SI_USER it appears
that no one cares about the signal specific si_code case and the
good solution is to just fix the architectures by using
a different si_code.
In none of the conversations has anyone even suggested that
anything depends on the signal specific redefinition of SI_USER.
There are at least test cases that care when si_code as 0 does
not work as si_user.
So make things simple and keep the generic code from introducing
problems by removing the special casing of TRAP_FIXME and FPE_FIXME.
This will ensure the generic case of sending a signal with
kill will always set SI_USER and work.
The architecture specific, and signal specific overloads that
set si_code to 0 will now have problems with signalfd and
the 32bit compat versions of siginfo copying. At least
until they are fixed.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Now that every instance of struct siginfo is now initialized it is no
longer necessary to copy struct siginfo piece by piece to userspace
but instead the entire structure can be copied.
As well as making the code simpler and more efficient this means that
copy_sinfo_to_user no longer cares which union member of struct
siginfo is in use.
In practice this means that all 32bit architectures that define
FPE_FIXME will handle properly send SI_USER when kill(SIGFPE) is sent.
While still performing their historic architectural brokenness when 0
is used a floating pointer signal. This matches the current behavior
of 64bit architectures that define FPE_FIXME who get lucky and an
overloaded SI_USER has continuted to work through copy_siginfo_to_user
because the 8 byte si_addr occupies the same bytes in struct siginfo
as the 4 byte si_pid and the 4 byte si_uid.
Problematic architectures still need to fix their ABI so that signalfd
and 32bit compat code will work properly.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.
Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.
The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.
In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.
Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
As originally committed do_revisn would deliver a siginfo for SIGILL
with an si_code composed of random stack contents. That makes no
sense and is not something userspace can depend on. So simplify
the code and just use "force_sig(SIG_ILL, current)" instead.
Fixes: 2923f5ea7738 ("nds32: Exception handling")
Cc: Vincent Chen <vincentc@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Neither unhandled_interrupt nor unhandled_exceptions fills in any of the
siginfo fields whend sending SIGKILL. Further because it is SIGKILL
even if all of the fields were filled out appropriately it would be impossible
for the process to read any of the siginfo fields. So simplfy things and
just use force_sig instead of force_sig_info.
Fixes: 2923f5ea7738 ("nds32: Exception handling")
Cc: Vincent Chen <vincentc@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
The call chain is:
breakpoint
notify_die
hw_breakpoint_exceptions_notify
hw_breakpoint_handler
So the signal number can only be SIGTRAP.
In hw_breakpoint_handler rc is either NOTIFY_STOP or NOTIF_DONE
both of which notifier_to_errno converts to 0. So si_errno is 0.
Historically si_addr was left unitialized in struct siginfo which is a
bug. There appears to be no consensus among the various architectures
which value should be in si_addr. So since no usable value has
been returned up to this point return NULL in si_addr.
Fixes: 4352fc1b12fa ("sh: Abstracted SH-4A UBC support on hw-breakpoint core.")
Fixes: 34d0b5af50a0 ("sh: Convert ptrace to hw_breakpoint API.")
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: linux-sh@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
Starting with commit v4.14-rc1~60^2^2~1, a SIGFPE signal sent via kill
results to wrong values in si_pid and si_uid fields of compat siginfo_t.
This happens due to FPE_FIXME being defined to 0 for sparc, and at the
same time siginfo_layout() introduced by the same commit returns
SIL_FAULT for SIGFPE if si_code == SI_USER and FPE_FIXME is defined to 0.
Fix this regression by removing FPE_FIXME macro and changing all its users
to assign FPE_FLTUNK to si_code instead of FPE_FIXME.
Note that FPE_FLTUNK is a new macro introduced by commit
266da65e9156d93e1126e185259a4aae68188d0e.
Tested with commit v4.16-11958-g16e205cf42da.
This bug was found by strace test suite.
In the discussion about FPE_FLTUNK on sparc David Miller said:
> Eric, feel free to do something similar on Sparc.
Link: https://github.com/strace/strace/issues/21
Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic")
Fixes: 2.3.41
Cc: David Miller <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Conceptually-Acked-By: David Miller <davem@davemloft.net>
Thanks-to: Anatoly Pugachev <matorola@gmail.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
|
Setting si_code to 0 is the same as setting si_code to SI_USER. This
is the same si_code as SI_USER. Posix and common sense requires that
SI_USER not be a signal specific si_code. As such this use of 0 for
the si_code is a pretty horribly broken ABI.
Cc: Helge Deller <deller@gmx.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-alpha@vger.kernel.org
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Ref: 0a635c7a84cf ("Fill in siginfo_t.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
|
|
|
The code to verify the new kernels sha digest is applicable for all
architectures. Move it to common code.
One problem is the string.c implementation on x86. Currently sha256
includes x86/boot/string.h which defines memcpy and memset to be gcc
builtins. By moving the sha256 implementation to common code and
changing the include to linux/string.h both functions are no longer
defined. Thus definitions have to be provided in x86/purgatory/string.c
Link: http://lkml.kernel.org/r/20180321112751.22196-12-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Patch series "kexec_file: Clean up purgatory load", v2.
Following the discussion with Dave and AKASHI, here are the common code
patches extracted from my recent patch set (Add kexec_file_load support
to s390) [1]. The patches were extracted to allow upstream integration
together with AKASHI's common code patches before the arch code gets
adjusted to the new base.
The reason for this series is to prepare common code for adding
kexec_file_load to s390 as well as cleaning up the mis-use of the
sh_offset field during purgatory load. In detail this series contains:
Patch #1&2: Minor cleanups/fixes.
Patch #3-9: Clean up the purgatory load/relocation code. Especially
remove the mis-use of the purgatory_info->sechdrs->sh_offset field,
currently holding a pointer into either kexec_purgatory (ro) or
purgatory_buf (rw) depending on the section. With these patches the
section address will be calculated verbosely and sh_offset will contain
the offset of the section in the stripped purgatory binary
(purgatory_buf).
Patch #10: Allows architectures to set the purgatory load address. This
patch is important for s390 as the kernel and purgatory have to be
loaded to fixed addresses. In current code this is impossible as the
purgatory load is opaque to the architecture.
Patch #11: Moves x86 purgatories sha implementation to common lib/
directory to allow reuse in other architectures.
This patch (of 11)
When building the kernel with CONFIG_KEXEC_FILE enabled gcc prints a
compile warning multiple times.
In file included from <path>/linux/init/initramfs.c:526:0:
<path>/include/linux/kexec.h:120:9: warning: `struct kimage' declared inside parameter list [enabled by default]
unsigned long cmdline_len);
^
This is because the typedefs for kexec_file_load uses struct kimage
before it is declared. Fix this by simply forward declaring struct
kimage.
Link: http://lkml.kernel.org/r/20180321112751.22196-2-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Removing bufp variable in prepare_elf64_headers() makes the code simpler
and more understandable.
Link: http://lkml.kernel.org/r/20180306102303.9063-7-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
While CRASH_MAX_RANGES (== 16) seems to be good enough, fixed-number
array is not a good idea in general.
In this patch, size of crash_mem buffer is calculated as before and the
buffer is now dynamically allocated. This change also allows removing
crash_elf_data structure.
Link: http://lkml.kernel.org/r/20180306102303.9063-6-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The code guarded by CONFIG_X86_64 is necessary on some architectures
which have a dedicated kernel mapping outside of linear memory mapping.
(arm64 is among those.)
In this patch, an additional argument, kernel_map, is added to enable/
disable the code removing #ifdef.
Link: http://lkml.kernel.org/r/20180306102303.9063-5-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
While prepare_elf64_headers() in x86 looks pretty generic for other
architectures' use, it contains some code which tries to list crash
memory regions by walking through system resources, which is not always
architecture agnostic. To make this function more generic, the related
code should be purged.
In this patch, prepare_elf64_headers() simply scans crash_mem buffer
passed and add all the listed regions to elf header as a PT_LOAD
segment. So walk_system_ram_res(prepare_elf64_headers_callback) have
been moved forward before prepare_elf64_headers() where the callback,
prepare_elf64_headers_callback(), is now responsible for filling up
crash_mem buffer.
Meanwhile exclude_elf_header_ranges() used to be called every time in
this callback it is rather redundant and now called only once in
prepare_elf_headers() as well.
Link: http://lkml.kernel.org/r/20180306102303.9063-4-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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 <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
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.html
This 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 <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
If module removes proc directory while another process pins it by
chdir'ing to it, then subsequent recreation of proc entry and all
entries down the tree will not be visible to any process until pinning
process unchdir from directory and unpins everything.
Steps to reproduce:
proc_mkdir("aaa", NULL);
proc_create("aaa/bbb", ...);
chdir("/proc/aaa");
remove_proc_entry("aaa/bbb", NULL);
remove_proc_entry("aaa", NULL);
proc_mkdir("aaa", NULL);
# inaccessible because "aaa" dentry still points
# to the original "aaa".
proc_create("aaa/bbb", ...);
Fix is to implement ->d_revalidate and ->d_delete.
Link: http://lkml.kernel.org/r/20180312201938.GA4871@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
cache_reap() is initially scheduled in start_cpu_timer() via
schedule_delayed_work_on(). But then the next iterations are scheduled
via schedule_delayed_work(), i.e. using WORK_CPU_UNBOUND.
Thus since commit ef557180447f ("workqueue: schedule WORK_CPU_UNBOUND
work on wq_unbound_cpumask CPUs") there is no guarantee the future
iterations will run on the originally intended cpu, although it's still
preferred. I was able to demonstrate this with
/sys/module/workqueue/parameters/debug_force_rr_cpu. IIUC, it may also
happen due to migrating timers in nohz context. As a result, some cpu's
would be calling cache_reap() more frequently and others never.
This patch uses schedule_delayed_work_on() with the current cpu when
scheduling the next iteration.
Link: http://lkml.kernel.org/r/20180411070007.32225-1-vbabka@suse.cz
Fixes: ef557180447f ("workqueue: schedule WORK_CPU_UNBOUND work on wq_unbound_cpumask CPUs")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Since commit 6326fec1122c ("mm: Use owner_priv bit for PageSwapCache,
valid when PageSwapBacked"), PG_swapcache is an alias for
PG_owner_priv_1, which may be also used for other purposes.
To know whether the bit indeed has the PG_swapcache meaning, it is
necessary to check PG_swapbacked, hence this bit must be exported.
Link: http://lkml.kernel.org/r/20180410161345.142e142d@ezekiel.suse.cz
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Xunlei Pang <xlpang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: "Marc-Andr Lureau" <marcandre.lureau@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
syzbot reported a use-after-free of shm_file_data(file)->file->f_op in
shm_get_unmapped_area(), called via sys_remap_file_pages().
Unfortunately it couldn't generate a reproducer, but I found a bug which
I think caused it. When remap_file_pages() is passed a full System V
shared memory segment, the memory is first unmapped, then a new map is
created using the ->vm_file. Between these steps, the shm ID can be
removed and reused for a new shm segment. But, shm_mmap() only checks
whether the ID is currently valid before calling the underlying file's
->mmap(); it doesn't check whether it was reused. Thus it can use the
wrong underlying file, one that was already freed.
Fix this by making the "outer" shm file (the one that gets put in
->vm_file) hold a reference to the real shm file, and by making
__shm_open() require that the file associated with the shm ID matches
the one associated with the "outer" file.
Taking the reference to the real shm file is needed to fully solve the
problem, since otherwise sfd->file could point to a freed file, which
then could be reallocated for the reused shm ID, causing the wrong shm
segment to be mapped (and without the required permission checks).
Commit 1ac0b6dec656 ("ipc/shm: handle removed segments gracefully in
shm_mmap()") almost fixed this bug, but it didn't go far enough because
it didn't consider the case where the shm ID is reused.
The following program usually reproduces this bug:
#include <stdlib.h>
#include <sys/shm.h>
#include <sys/syscall.h>
#include <unistd.h>
int main()
{
int is_parent = (fork() != 0);
srand(getpid());
for (;;) {
int id = shmget(0xF00F, 4096, IPC_CREAT|0700);
if (is_parent) {
void *addr = shmat(id, NULL, 0);
usleep(rand() % 50);
while (!syscall(__NR_remap_file_pages, addr, 4096, 0, 0, 0));
} else {
usleep(rand() % 50);
shmctl(id, IPC_RMID, NULL);
}
}
}
It causes the following NULL pointer dereference due to a 'struct file'
being used while it's being freed. (I couldn't actually get a KASAN
use-after-free splat like in the syzbot report. But I think it's
possible with this bug; it would just take a more extraordinary race...)
BUG: unable to handle kernel NULL pointer dereference at 0000000000000058
PGD 0 P4D 0
Oops: 0000 [#1] SMP NOPTI
CPU: 9 PID: 258 Comm: syz_ipc Not tainted 4.16.0-05140-gf8cf2f16a7c95 #189
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
RIP: 0010:d_inode include/linux/dcache.h:519 [inline]
RIP: 0010:touch_atime+0x25/0xd0 fs/inode.c:1724
[...]
Call Trace:
file_accessed include/linux/fs.h:2063 [inline]
shmem_mmap+0x25/0x40 mm/shmem.c:2149
call_mmap include/linux/fs.h:1789 [inline]
shm_mmap+0x34/0x80 ipc/shm.c:465
call_mmap include/linux/fs.h:1789 [inline]
mmap_region+0x309/0x5b0 mm/mmap.c:1712
do_mmap+0x294/0x4a0 mm/mmap.c:1483
do_mmap_pgoff include/linux/mm.h:2235 [inline]
SYSC_remap_file_pages mm/mmap.c:2853 [inline]
SyS_remap_file_pages+0x232/0x310 mm/mmap.c:2769
do_syscall_64+0x64/0x1a0 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ebiggers@google.com: add comment]
Link: http://lkml.kernel.org/r/20180410192850.235835-1-ebiggers3@gmail.com
Link: http://lkml.kernel.org/r/20180409043039.28915-1-ebiggers3@gmail.com
Reported-by: syzbot+d11f321e7f1923157eac80aa990b446596f46439@syzkaller.appspotmail.com
Fixes: c8d78c1823f4 ("mm: replace remap_file_pages() syscall with emulation")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Building orangefs on MMU-less machines now results in a link error
because of the newly introduced use of the filemap_page_mkwrite()
function:
ERROR: "filemap_page_mkwrite" [fs/orangefs/orangefs.ko] undefined!
This adds a dummy version for it, similar to the existing
generic_file_mmap and generic_file_readonly_mmap stubs in the same file,
to avoid the link error without adding #ifdefs in each file system that
uses these.
Link: http://lkml.kernel.org/r/20180409105555.2439976-1-arnd@arndb.de
Fixes: a5135eeab2e5 ("orangefs: implement vm_ops->fault")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Martin Brandenburg <martin@omnibond.com>
Cc: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
__get_user_pages_fast handles errors differently from
get_user_pages_fast: the former always returns the number of pages
pinned, the later might return a negative error code.
Link: http://lkml.kernel.org/r/1522962072-182137-6-git-send-email-mst@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
get_user_pages_fast is supposed to be a faster drop-in equivalent of
get_user_pages. As such, callers expect it to return a negative return
code when passed an invalid address, and never expect it to return 0
when passed a positive number of pages, since its documentation says:
* Returns number of pages pinned. This may be fewer than the number
* requested. If nr_pages is 0 or negative, returns 0. If no pages
* were pinned, returns -errno.
When get_user_pages_fast fall back on get_user_pages this is exactly
what happens. Unfortunately the implementation is inconsistent: it
returns 0 if passed a kernel address, confusing callers: for example,
the following is pretty common but does not appear to do the right thing
with a kernel address:
ret = get_user_pages_fast(addr, 1, writeable, &page);
if (ret < 0)
return ret;
Change get_user_pages_fast to return -EFAULT when supplied a kernel
address to make it match expectations.
All callers have been audited for consistency with the documented
semantics.
Link: http://lkml.kernel.org/r/1522962072-182137-4-git-send-email-mst@redhat.com
Fixes: 5b65c4677a57 ("mm, x86/mm: Fix performance regression in get_user_pages_fast()")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reported-by: syzbot+6304bf97ef436580fede@syzkaller.appspotmail.com
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Patch series "mm/get_user_pages_fast fixes, cleanups", v2.
Turns out get_user_pages_fast and __get_user_pages_fast return different
values on error when given a single page: __get_user_pages_fast returns
0. get_user_pages_fast returns either 0 or an error.
Callers of get_user_pages_fast expect an error so fix it up to return an
error consistently.
Stress the difference between get_user_pages_fast and
__get_user_pages_fast to make sure callers aren't confused.
This patch (of 3):
__gup_benchmark_ioctl does not handle the case where get_user_pages_fast
fails:
- a negative return code will cause a buffer overrun
- returning with partial success will cause use of uninitialized
memory.
[akpm@linux-foundation.org: simplification]
Link: http://lkml.kernel.org/r/1522962072-182137-3-git-send-email-mst@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
We've got a bug report indicating a kernel panic at booting on an x86-32
system, and it turned out to be the invalid PCI resource assigned after
reallocation. __find_resource() first aligns the resource start address
and resets the end address with start+size-1 accordingly, then checks
whether it's contained. Here the end address may overflow the integer,
although resource_contains() still returns true because the function
validates only start and end address. So this ends up with returning an
invalid resource (start > end).
There was already an attempt to cover such a problem in the commit
47ea91b4052d ("Resource: fix wrong resource window calculation"), but
this case is an overseen one.
This patch adds the validity check of the newly calculated resource for
avoiding the integer overflow problem.
Bugzilla: http://bugzilla.opensuse.org/show_bug.cgi?id=1086739
Link: http://lkml.kernel.org/r/s5hpo37d5l8.wl-tiwai@suse.de
Fixes: 23c570a67448 ("resource: ability to resize an allocated resource")
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reported-by: Michael Henders <hendersm@shaw.ca>
Tested-by: Michael Henders <hendersm@shaw.ca>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
We at Red Hat/Fedora have generally tried to have a per file breakdown of
every config option we set. This makes it easy for us to add new options
when they are exposed and keep a changelog of why they were set.
A Fedora example is here:
https://src.fedoraproject.org/cgit/rpms/kernel.git/tree/configs/fedora/generic
Using various merge scripts, we build up a config file and run it through
'make listnewconfig' and 'make oldnoconfig'. The idea is to print out new
config options that haven't been manually set and use the default until
a patch is posted to set it properly.
To speed things up, it would be nice to make it easier to generate a
patch to post the default setting. The output of 'make listnewconfig'
has two issues that limit us:
- it doesn't provide the default value
- it doesn't provide the new 'choice' options that get flagged in
'oldconfig'
This patch extends 'listnewconfig' to address the above two issues.
This allows us to run a script
make listnewconfig | rhconfig-tool -o patches; git send-email patches/
The output of 'make listnewconfig':
CONFIG_NET_EMATCH_IPT
CONFIG_IPVLAN
CONFIG_ICE
CONFIG_NET_VENDOR_NI
CONFIG_IEEE802154_MCR20A
CONFIG_IR_IMON_DECODER
CONFIG_IR_IMON_RAW
The new output of 'make listnewconfig':
CONFIG_KERNEL_XZ=n
CONFIG_KERNEL_LZO=n
CONFIG_NET_EMATCH_IPT=n
CONFIG_IPVLAN=n
CONFIG_ICE=n
CONFIG_NET_VENDOR_NI=y
CONFIG_IEEE802154_MCR20A=n
CONFIG_IR_IMON_DECODER=n
CONFIG_IR_IMON_RAW=n
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
|
Eric W. Biederman
Dmitry V. Levin
Linus Torvalds
Philipp Rudo
AKASHI Takahiro
Alexey Dobriyan
Vlastimil Babka
Petr Tesarik
Eric Biggers
Arnd Bergmann
Michael S. Tsirkin
Takashi Iwai
Don Zickus