linux-stable.git/arch/nios2/kernel, branch linux-5.15.y Linux kernel stable tree nios2: ensure that memblock.current_limit is set when setting pfn limits 2025-10-29T13:03:10+00:00 Simon Schuster schuster.simon@siemens-energy.com 2025-08-21T10:37:07+00:00 25f09699edd360b534ccae16bc276c3b52c471f3 [ Upstream commit a20b83cf45be2057f3d073506779e52c7fa17f94 ] On nios2, with CONFIG_FLATMEM set, the kernel relies on memblock_get_current_limit() to determine the limits of mem_map, in particular for max_low_pfn. Unfortunately, memblock.current_limit is only default initialized to MEMBLOCK_ALLOC_ANYWHERE at this point of the bootup, potentially leading to situations where max_low_pfn can erroneously exceed the value of max_pfn and, thus, the valid range of available DRAM. This can in turn cause kernel-level paging failures, e.g.: [ 76.900000] Unable to handle kernel paging request at virtual address 20303000 [ 76.900000] ea = c0080890, ra = c000462c, cause = 14 [ 76.900000] Kernel panic - not syncing: Oops [ 76.900000] ---[ end Kernel panic - not syncing: Oops ]--- This patch fixes this by pre-calculating memblock.current_limit based on the upper limits of the available memory ranges via adjust_lowmem_bounds, a simplified version of the equivalent implementation within the arm architecture. Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com> Signed-off-by: Andreas Oetken <andreas.oetken@siemens-energy.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit a20b83cf45be2057f3d073506779e52c7fa17f94 ]

On nios2, with CONFIG_FLATMEM set, the kernel relies on
memblock_get_current_limit() to determine the limits of mem_map, in
particular for max_low_pfn.
Unfortunately, memblock.current_limit is only default initialized to
MEMBLOCK_ALLOC_ANYWHERE at this point of the bootup, potentially leading
to situations where max_low_pfn can erroneously exceed the value of
max_pfn and, thus, the valid range of available DRAM.

This can in turn cause kernel-level paging failures, e.g.:

[   76.900000] Unable to handle kernel paging request at virtual address 20303000
[   76.900000] ea = c0080890, ra = c000462c, cause = 14
[   76.900000] Kernel panic - not syncing: Oops
[   76.900000] ---[ end Kernel panic - not syncing: Oops ]---

This patch fixes this by pre-calculating memblock.current_limit
based on the upper limits of the available memory ranges via
adjust_lowmem_bounds, a simplified version of the equivalent
implementation within the arm architecture.

Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com>
Signed-off-by: Andreas Oetken <andreas.oetken@siemens-energy.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sched: Add wrapper for get_wchan() to keep task blocked 2025-08-28T14:24:03+00:00 Kees Cook keescook@chromium.org 2021-09-29T22:02:14+00:00 5ce1264b586d53775f69769606e8c4afcbd7f85c commit 42a20f86dc19f9282d974df0ba4d226c865ab9dd upstream. Having a stable wchan means the process must be blocked and for it to stay that way while performing stack unwinding. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm] Tested-by: Mark Rutland <mark.rutland@arm.com> [arm64] Link: https://lkml.kernel.org/r/20211008111626.332092234@infradead.org Signed-off-by: Siddhi Katage <siddhi.katage@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 42a20f86dc19f9282d974df0ba4d226c865ab9dd upstream.

Having a stable wchan means the process must be blocked and for it to
stay that way while performing stack unwinding.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm]
Tested-by: Mark Rutland <mark.rutland@arm.com> [arm64]
Link: https://lkml.kernel.org/r/20211008111626.332092234@infradead.org
Signed-off-by: Siddhi Katage <siddhi.katage@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
exit: Add and use make_task_dead. 2023-02-01T07:27:20+00:00 Eric W. Biederman ebiederm@xmission.com 2023-01-24T18:50:56+00:00 39a26d872178423acf46cb001954e2ac2730b117 commit 0e25498f8cd43c1b5aa327f373dd094e9a006da7 upstream. There are two big uses of do_exit. The first is it's design use to be the guts of the exit(2) system call. The second use is to terminate a task after something catastrophic has happened like a NULL pointer in kernel code. Add a function make_task_dead that is initialy exactly the same as do_exit to cover the cases where do_exit is called to handle catastrophic failure. In time this can probably be reduced to just a light wrapper around do_task_dead. For now keep it exactly the same so that there will be no behavioral differences introducing this new concept. Replace all of the uses of do_exit that use it for catastraphic task cleanup with make_task_dead to make it clear what the code is doing. As part of this rename rewind_stack_do_exit rewind_stack_and_make_dead. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit 0e25498f8cd43c1b5aa327f373dd094e9a006da7 upstream.

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
nios2: add force_successful_syscall_return() 2022-08-25T09:40:19+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:09:45+00:00 8af269e5bdf427b2fb79d132e2fb6d9ba9941a58 commit fd0c153daad135d0ec1a53c5dbe6936a724d6ae1 upstream. If we use the ancient SysV syscall ABI, we'd better have tell the kernel how to claim that a negative return value is a success. Use ->orig_r2 for that - it's inaccessible via ptrace, so it's a fair game for changes and it's normally[*] non-negative on return from syscall. Set to -1; syscall is not going to be restart-worthy by definition, so we won't interfere with that use either. [*] the only exception is rt_sigreturn(), where we skip the entire messing with r1/r2 anyway. Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fd0c153daad135d0ec1a53c5dbe6936a724d6ae1 upstream.

If we use the ancient SysV syscall ABI, we'd better have tell the
kernel how to claim that a negative return value is a success.
Use ->orig_r2 for that - it's inaccessible via ptrace, so it's
a fair game for changes and it's normally[*] non-negative on return
from syscall.  Set to -1; syscall is not going to be restart-worthy
by definition, so we won't interfere with that use either.

[*] the only exception is rt_sigreturn(), where we skip the entire
messing with r1/r2 anyway.

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: restarts apply only to the first sigframe we build... 2022-08-25T09:40:18+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:09:16+00:00 c9f78def88569d6e96c95618a9fbbba4861d8cee commit 411a76b7219555c55867466c82d70ce928d6c9e1 upstream. Fixes: b53e906d255d ("nios2: Signal handling support") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 411a76b7219555c55867466c82d70ce928d6c9e1 upstream.

Fixes: b53e906d255d ("nios2: Signal handling support")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: fix syscall restart checks 2022-08-25T09:40:18+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:08:48+00:00 3bee7b77d917e12de7d4c6e3a155cf00cdb61472 commit 2d631bd58fe0ea3e3350212e23c9aba1fb606514 upstream. sys_foo() returns -512 (aka -ERESTARTSYS) => do_signal() sees 512 in r2 and 1 in r1. sys_foo() returns 512 => do_signal() sees 512 in r2 and 0 in r1. The former is restart-worthy; the latter obviously isn't. Fixes: b53e906d255d ("nios2: Signal handling support") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 2d631bd58fe0ea3e3350212e23c9aba1fb606514 upstream.

sys_foo() returns -512 (aka -ERESTARTSYS) => do_signal() sees
512 in r2 and 1 in r1.

sys_foo() returns 512 => do_signal() sees 512 in r2 and 0 in r1.

The former is restart-worthy; the latter obviously isn't.

Fixes: b53e906d255d ("nios2: Signal handling support")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: traced syscall does need to check the syscall number 2022-08-25T09:40:18+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:07:21+00:00 f794d1fe6e528d055ea9149b61905e5feb909b14 commit 25ba820ef36bdbaf9884adeac69b6e1821a7df76 upstream. all checks done before letting the tracer modify the register state are worthless... Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 25ba820ef36bdbaf9884adeac69b6e1821a7df76 upstream.

all checks done before letting the tracer modify the register
state are worthless...

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: don't leave NULLs in sys_call_table[] 2022-08-25T09:40:18+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:06:46+00:00 80cae5d810d260fc3026fd1a9c3aacadb14d74a1 commit 45ec746c65097c25e77d24eae8fee0def5b6cc5d upstream. fill the gaps in there with sys_ni_syscall, as everyone does... Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 45ec746c65097c25e77d24eae8fee0def5b6cc5d upstream.

fill the gaps in there with sys_ni_syscall, as everyone does...

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: page fault et.al. are *not* restartable syscalls... 2022-08-25T09:40:17+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:06:04+00:00 35d5fd70e8c8d568b6dbeee62d6b6dcc612a1b92 commit 8535c239ac674f7ead0f2652932d35c52c4123b2 upstream. make sure that ->orig_r2 is negative for everything except the syscalls. Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8535c239ac674f7ead0f2652932d35c52c4123b2 upstream.

make sure that ->orig_r2 is negative for everything except
the syscalls.

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
uaccess: fix type mismatch warnings from access_ok() 2022-04-08T12:24:01+00:00 Arnd Bergmann arnd@arndb.de 2022-02-14T19:22:10+00:00 8b2a6074b981488ceeabf5ef7b5f873340e75118 [ Upstream commit 23fc539e81295b14b50c6ccc5baeb4f3d59d822d ] On some architectures, access_ok() does not do any argument type checking, so replacing the definition with a generic one causes a few warnings for harmless issues that were never caught before. Fix the ones that I found either through my own test builds or that were reported by the 0-day bot. Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 23fc539e81295b14b50c6ccc5baeb4f3d59d822d ]

On some architectures, access_ok() does not do any argument type
checking, so replacing the definition with a generic one causes
a few warnings for harmless issues that were never caught before.

Fix the ones that I found either through my own test builds or
that were reported by the 0-day bot.

Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>