--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:45 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:53 -0800
+Subject: docs: Fix path paste-o for /sys/kernel/warn_count
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, kernel test robot <lkp@intel.com>
+Message-ID: <20230203003354.85691-15-ebiggers@kernel.org>
+
+From: Kees Cook <keescook@chromium.org>
+
+commit 00dd027f721e0458418f7750d8a5a664ed3e5994 upstream.
+
+Running "make htmldocs" shows that "/sys/kernel/oops_count" was
+duplicated. This should have been "warn_count":
+
+ Warning: /sys/kernel/oops_count is defined 2 times:
+ ./Documentation/ABI/testing/sysfs-kernel-warn_count:0
+ ./Documentation/ABI/testing/sysfs-kernel-oops_count:0
+
+Fix the typo.
+
+Reported-by: kernel test robot <lkp@intel.com>
+Link: https://lore.kernel.org/linux-doc/202212110529.A3Qav8aR-lkp@intel.com
+Fixes: 8b05aa263361 ("panic: Expose "warn_count" to sysfs")
+Cc: linux-hardening@vger.kernel.org
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ Documentation/ABI/testing/sysfs-kernel-warn_count | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/Documentation/ABI/testing/sysfs-kernel-warn_count
++++ b/Documentation/ABI/testing/sysfs-kernel-warn_count
+@@ -1,4 +1,4 @@
+-What: /sys/kernel/oops_count
++What: /sys/kernel/warn_count
+ Date: November 2022
+ KernelVersion: 6.2.0
+ Contact: Linux Kernel Hardening List <linux-hardening@vger.kernel.org>
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:45 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:42 -0800
+Subject: exit: Add and use make_task_dead.
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org
+Message-ID: <20230203003354.85691-4-ebiggers@kernel.org>
+
+From: "Eric W. Biederman" <ebiederm@xmission.com>
+
+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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/alpha/kernel/traps.c | 6 +++---
+ arch/alpha/mm/fault.c | 2 +-
+ arch/arm/kernel/traps.c | 2 +-
+ arch/arm/mm/fault.c | 2 +-
+ arch/arm64/kernel/traps.c | 2 +-
+ arch/arm64/mm/fault.c | 2 +-
+ arch/h8300/kernel/traps.c | 2 +-
+ arch/h8300/mm/fault.c | 2 +-
+ arch/hexagon/kernel/traps.c | 2 +-
+ arch/ia64/kernel/mca_drv.c | 2 +-
+ arch/ia64/kernel/traps.c | 2 +-
+ arch/ia64/mm/fault.c | 2 +-
+ arch/m68k/kernel/traps.c | 2 +-
+ arch/m68k/mm/fault.c | 2 +-
+ arch/microblaze/kernel/exceptions.c | 4 ++--
+ arch/mips/kernel/traps.c | 2 +-
+ arch/nios2/kernel/traps.c | 4 ++--
+ arch/openrisc/kernel/traps.c | 2 +-
+ arch/parisc/kernel/traps.c | 2 +-
+ arch/powerpc/kernel/traps.c | 2 +-
+ arch/s390/kernel/dumpstack.c | 2 +-
+ arch/s390/kernel/nmi.c | 2 +-
+ arch/sh/kernel/traps.c | 2 +-
+ arch/sparc/kernel/traps_32.c | 4 +---
+ arch/sparc/kernel/traps_64.c | 4 +---
+ arch/x86/entry/entry_32.S | 6 +++---
+ arch/x86/entry/entry_64.S | 6 +++---
+ arch/x86/kernel/dumpstack.c | 4 ++--
+ arch/xtensa/kernel/traps.c | 2 +-
+ include/linux/sched/task.h | 1 +
+ kernel/exit.c | 9 +++++++++
+ tools/objtool/check.c | 3 ++-
+ 32 files changed, 50 insertions(+), 43 deletions(-)
+
+--- a/arch/alpha/kernel/traps.c
++++ b/arch/alpha/kernel/traps.c
+@@ -192,7 +192,7 @@ die_if_kernel(char * str, struct pt_regs
+ local_irq_enable();
+ while (1);
+ }
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+
+ #ifndef CONFIG_MATHEMU
+@@ -609,7 +609,7 @@ do_entUna(void * va, unsigned long opcod
+
+ printk("Bad unaligned kernel access at %016lx: %p %lx %lu\n",
+ pc, va, opcode, reg);
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+
+ got_exception:
+ /* Ok, we caught the exception, but we don't want it. Is there
+@@ -664,7 +664,7 @@ got_exception:
+ local_irq_enable();
+ while (1);
+ }
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+
+ /*
+--- a/arch/alpha/mm/fault.c
++++ b/arch/alpha/mm/fault.c
+@@ -206,7 +206,7 @@ retry:
+ printk(KERN_ALERT "Unable to handle kernel paging request at "
+ "virtual address %016lx\n", address);
+ die_if_kernel("Oops", regs, cause, (unsigned long*)regs - 16);
+- do_exit(SIGKILL);
++ make_task_dead(SIGKILL);
+
+ /* We ran out of memory, or some other thing happened to us that
+ made us unable to handle the page fault gracefully. */
+--- a/arch/arm/kernel/traps.c
++++ b/arch/arm/kernel/traps.c
+@@ -342,7 +342,7 @@ static void oops_end(unsigned long flags
+ if (panic_on_oops)
+ panic("Fatal exception");
+ if (signr)
+- do_exit(signr);
++ make_task_dead(signr);
+ }
+
+ /*
+--- a/arch/arm/mm/fault.c
++++ b/arch/arm/mm/fault.c
+@@ -150,7 +150,7 @@ __do_kernel_fault(struct mm_struct *mm,
+ show_pte(mm, addr);
+ die("Oops", regs, fsr);
+ bust_spinlocks(0);
+- do_exit(SIGKILL);
++ make_task_dead(SIGKILL);
+ }
+
+ /*
+--- a/arch/arm64/kernel/traps.c
++++ b/arch/arm64/kernel/traps.c
+@@ -223,7 +223,7 @@ void die(const char *str, struct pt_regs
+ raw_spin_unlock_irqrestore(&die_lock, flags);
+
+ if (ret != NOTIFY_STOP)
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+
+ void arm64_notify_die(const char *str, struct pt_regs *regs,
+--- a/arch/arm64/mm/fault.c
++++ b/arch/arm64/mm/fault.c
+@@ -288,7 +288,7 @@ static void __do_kernel_fault(unsigned l
+ show_pte(addr);
+ die("Oops", regs, esr);
+ bust_spinlocks(0);
+- do_exit(SIGKILL);
++ make_task_dead(SIGKILL);
+ }
+
+ /*
+--- a/arch/h8300/kernel/traps.c
++++ b/arch/h8300/kernel/traps.c
+@@ -110,7 +110,7 @@ void die(const char *str, struct pt_regs
+ dump(fp);
+
+ spin_unlock_irq(&die_lock);
+- do_exit(SIGSEGV);
++ make_dead_task(SIGSEGV);
+ }
+
+ static int kstack_depth_to_print = 24;
+--- a/arch/h8300/mm/fault.c
++++ b/arch/h8300/mm/fault.c
+@@ -52,7 +52,7 @@ asmlinkage int do_page_fault(struct pt_r
+ printk(" at virtual address %08lx\n", address);
+ if (!user_mode(regs))
+ die("Oops", regs, error_code);
+- do_exit(SIGKILL);
++ make_dead_task(SIGKILL);
+
+ return 1;
+ }
+--- a/arch/hexagon/kernel/traps.c
++++ b/arch/hexagon/kernel/traps.c
+@@ -234,7 +234,7 @@ int die(const char *str, struct pt_regs
+ panic("Fatal exception");
+
+ oops_exit();
+- do_exit(err);
++ make_dead_task(err);
+ return 0;
+ }
+
+--- a/arch/ia64/kernel/mca_drv.c
++++ b/arch/ia64/kernel/mca_drv.c
+@@ -176,7 +176,7 @@ mca_handler_bh(unsigned long paddr, void
+ spin_unlock(&mca_bh_lock);
+
+ /* This process is about to be killed itself */
+- do_exit(SIGKILL);
++ make_task_dead(SIGKILL);
+ }
+
+ /**
+--- a/arch/ia64/kernel/traps.c
++++ b/arch/ia64/kernel/traps.c
+@@ -85,7 +85,7 @@ die (const char *str, struct pt_regs *re
+ if (panic_on_oops)
+ panic("Fatal exception");
+
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ return 0;
+ }
+
+--- a/arch/ia64/mm/fault.c
++++ b/arch/ia64/mm/fault.c
+@@ -300,7 +300,7 @@ retry:
+ regs = NULL;
+ bust_spinlocks(0);
+ if (regs)
+- do_exit(SIGKILL);
++ make_task_dead(SIGKILL);
+ return;
+
+ out_of_memory:
+--- a/arch/m68k/kernel/traps.c
++++ b/arch/m68k/kernel/traps.c
+@@ -1141,7 +1141,7 @@ void die_if_kernel (char *str, struct pt
+ pr_crit("%s: %08x\n", str, nr);
+ show_registers(fp);
+ add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+
+ asmlinkage void set_esp0(unsigned long ssp)
+--- a/arch/m68k/mm/fault.c
++++ b/arch/m68k/mm/fault.c
+@@ -50,7 +50,7 @@ int send_fault_sig(struct pt_regs *regs)
+ pr_alert("Unable to handle kernel access");
+ pr_cont(" at virtual address %p\n", siginfo.si_addr);
+ die_if_kernel("Oops", regs, 0 /*error_code*/);
+- do_exit(SIGKILL);
++ make_task_dead(SIGKILL);
+ }
+
+ return 1;
+--- a/arch/microblaze/kernel/exceptions.c
++++ b/arch/microblaze/kernel/exceptions.c
+@@ -44,10 +44,10 @@ void die(const char *str, struct pt_regs
+ pr_warn("Oops: %s, sig: %ld\n", str, err);
+ show_regs(fp);
+ spin_unlock_irq(&die_lock);
+- /* do_exit() should take care of panic'ing from an interrupt
++ /* make_task_dead() should take care of panic'ing from an interrupt
+ * context so we don't handle it here
+ */
+- do_exit(err);
++ make_task_dead(err);
+ }
+
+ /* for user application debugging */
+--- a/arch/mips/kernel/traps.c
++++ b/arch/mips/kernel/traps.c
+@@ -414,7 +414,7 @@ void __noreturn die(const char *str, str
+ if (regs && kexec_should_crash(current))
+ crash_kexec(regs);
+
+- do_exit(sig);
++ make_task_dead(sig);
+ }
+
+ extern struct exception_table_entry __start___dbe_table[];
+--- a/arch/nios2/kernel/traps.c
++++ b/arch/nios2/kernel/traps.c
+@@ -43,10 +43,10 @@ void die(const char *str, struct pt_regs
+ show_regs(regs);
+ spin_unlock_irq(&die_lock);
+ /*
+- * do_exit() should take care of panic'ing from an interrupt
++ * make_task_dead() should take care of panic'ing from an interrupt
+ * context so we don't handle it here
+ */
+- do_exit(err);
++ make_task_dead(err);
+ }
+
+ void _exception(int signo, struct pt_regs *regs, int code, unsigned long addr)
+--- a/arch/openrisc/kernel/traps.c
++++ b/arch/openrisc/kernel/traps.c
+@@ -265,7 +265,7 @@ void die(const char *str, struct pt_regs
+ __asm__ __volatile__("l.nop 1");
+ do {} while (1);
+ #endif
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+
+ /* This is normally the 'Oops' routine */
+--- a/arch/parisc/kernel/traps.c
++++ b/arch/parisc/kernel/traps.c
+@@ -290,7 +290,7 @@ void die_if_kernel(char *str, struct pt_
+ panic("Fatal exception");
+
+ oops_exit();
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+
+ /* gdb uses break 4,8 */
+--- a/arch/powerpc/kernel/traps.c
++++ b/arch/powerpc/kernel/traps.c
+@@ -211,7 +211,7 @@ static void oops_end(unsigned long flags
+ panic("Fatal exception in interrupt");
+ if (panic_on_oops)
+ panic("Fatal exception");
+- do_exit(signr);
++ make_task_dead(signr);
+ }
+ NOKPROBE_SYMBOL(oops_end);
+
+--- a/arch/s390/kernel/dumpstack.c
++++ b/arch/s390/kernel/dumpstack.c
+@@ -186,5 +186,5 @@ void die(struct pt_regs *regs, const cha
+ if (panic_on_oops)
+ panic("Fatal exception: panic_on_oops");
+ oops_exit();
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+--- a/arch/s390/kernel/nmi.c
++++ b/arch/s390/kernel/nmi.c
+@@ -94,7 +94,7 @@ void s390_handle_mcck(void)
+ "malfunction (code 0x%016lx).\n", mcck.mcck_code);
+ printk(KERN_EMERG "mcck: task: %s, pid: %d.\n",
+ current->comm, current->pid);
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+ }
+ EXPORT_SYMBOL_GPL(s390_handle_mcck);
+--- a/arch/sh/kernel/traps.c
++++ b/arch/sh/kernel/traps.c
+@@ -57,7 +57,7 @@ void die(const char *str, struct pt_regs
+ if (panic_on_oops)
+ panic("Fatal exception");
+
+- do_exit(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+
+ void die_if_kernel(const char *str, struct pt_regs *regs, long err)
+--- a/arch/sparc/kernel/traps_32.c
++++ b/arch/sparc/kernel/traps_32.c
+@@ -86,9 +86,7 @@ void __noreturn die_if_kernel(char *str,
+ }
+ printk("Instruction DUMP:");
+ instruction_dump ((unsigned long *) regs->pc);
+- if(regs->psr & PSR_PS)
+- do_exit(SIGKILL);
+- do_exit(SIGSEGV);
++ make_task_dead((regs->psr & PSR_PS) ? SIGKILL : SIGSEGV);
+ }
+
+ void do_hw_interrupt(struct pt_regs *regs, unsigned long type)
+--- a/arch/sparc/kernel/traps_64.c
++++ b/arch/sparc/kernel/traps_64.c
+@@ -2547,9 +2547,7 @@ void __noreturn die_if_kernel(char *str,
+ }
+ if (panic_on_oops)
+ panic("Fatal exception");
+- if (regs->tstate & TSTATE_PRIV)
+- do_exit(SIGKILL);
+- do_exit(SIGSEGV);
++ make_task_dead((regs->tstate & TSTATE_PRIV)? SIGKILL : SIGSEGV);
+ }
+ EXPORT_SYMBOL(die_if_kernel);
+
+--- a/arch/x86/entry/entry_32.S
++++ b/arch/x86/entry/entry_32.S
+@@ -1068,13 +1068,13 @@ ENTRY(async_page_fault)
+ END(async_page_fault)
+ #endif
+
+-ENTRY(rewind_stack_do_exit)
++ENTRY(rewind_stack_and_make_dead)
+ /* Prevent any naive code from trying to unwind to our caller. */
+ xorl %ebp, %ebp
+
+ movl PER_CPU_VAR(cpu_current_top_of_stack), %esi
+ leal -TOP_OF_KERNEL_STACK_PADDING-PTREGS_SIZE(%esi), %esp
+
+- call do_exit
++ call make_task_dead
+ 1: jmp 1b
+-END(rewind_stack_do_exit)
++END(rewind_stack_and_make_dead)
+--- a/arch/x86/entry/entry_64.S
++++ b/arch/x86/entry/entry_64.S
+@@ -1672,7 +1672,7 @@ ENTRY(ignore_sysret)
+ sysretl
+ END(ignore_sysret)
+
+-ENTRY(rewind_stack_do_exit)
++ENTRY(rewind_stack_and_make_dead)
+ UNWIND_HINT_FUNC
+ /* Prevent any naive code from trying to unwind to our caller. */
+ xorl %ebp, %ebp
+@@ -1681,5 +1681,5 @@ ENTRY(rewind_stack_do_exit)
+ leaq -PTREGS_SIZE(%rax), %rsp
+ UNWIND_HINT_REGS
+
+- call do_exit
+-END(rewind_stack_do_exit)
++ call make_task_dead
++END(rewind_stack_and_make_dead)
+--- a/arch/x86/kernel/dumpstack.c
++++ b/arch/x86/kernel/dumpstack.c
+@@ -271,7 +271,7 @@ unsigned long oops_begin(void)
+ EXPORT_SYMBOL_GPL(oops_begin);
+ NOKPROBE_SYMBOL(oops_begin);
+
+-void __noreturn rewind_stack_do_exit(int signr);
++void __noreturn rewind_stack_and_make_dead(int signr);
+
+ void oops_end(unsigned long flags, struct pt_regs *regs, int signr)
+ {
+@@ -303,7 +303,7 @@ void oops_end(unsigned long flags, struc
+ * reuse the task stack and that existing poisons are invalid.
+ */
+ kasan_unpoison_task_stack(current);
+- rewind_stack_do_exit(signr);
++ rewind_stack_and_make_dead(signr);
+ }
+ NOKPROBE_SYMBOL(oops_end);
+
+--- a/arch/xtensa/kernel/traps.c
++++ b/arch/xtensa/kernel/traps.c
+@@ -547,5 +547,5 @@ void die(const char * str, struct pt_reg
+ if (panic_on_oops)
+ panic("Fatal exception");
+
+- do_exit(err);
++ make_task_dead(err);
+ }
+--- a/include/linux/sched/task.h
++++ b/include/linux/sched/task.h
+@@ -36,6 +36,7 @@ extern int sched_fork(unsigned long clon
+ extern void sched_dead(struct task_struct *p);
+
+ void __noreturn do_task_dead(void);
++void __noreturn make_task_dead(int signr);
+
+ extern void proc_caches_init(void);
+
+--- a/kernel/exit.c
++++ b/kernel/exit.c
+@@ -920,6 +920,15 @@ void __noreturn do_exit(long code)
+ }
+ EXPORT_SYMBOL_GPL(do_exit);
+
++void __noreturn make_task_dead(int signr)
++{
++ /*
++ * Take the task off the cpu after something catastrophic has
++ * happened.
++ */
++ do_exit(signr);
++}
++
+ void complete_and_exit(struct completion *comp, long code)
+ {
+ if (comp)
+--- a/tools/objtool/check.c
++++ b/tools/objtool/check.c
+@@ -159,6 +159,7 @@ static int __dead_end_function(struct ob
+ "panic",
+ "do_exit",
+ "do_task_dead",
++ "make_task_dead",
+ "__module_put_and_exit",
+ "complete_and_exit",
+ "kvm_spurious_fault",
+@@ -166,7 +167,7 @@ static int __dead_end_function(struct ob
+ "lbug_with_loc",
+ "fortify_panic",
+ "machine_real_restart",
+- "rewind_stack_do_exit",
++ "rewind_stack_and_make_dead"
+ };
+
+ if (func->bind == STB_WEAK)
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:54 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:49 -0800
+Subject: exit: Allow oops_limit to be disabled
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>, Andrew Morton <akpm@linux-foundation.org>, Baolin Wang <baolin.wang@linux.alibaba.com>, "Jason A. Donenfeld" <Jason@zx2c4.com>, Eric Biggers <ebiggers@google.com>, Huang Ying <ying.huang@intel.com>, Arnd Bergmann <arnd@arndb.de>, linux-doc@vger.kernel.org
+Message-ID: <20230203003354.85691-11-ebiggers@kernel.org>
+
+From: Kees Cook <keescook@chromium.org>
+
+commit de92f65719cd672f4b48397540b9f9eff67eca40 upstream.
+
+In preparation for keeping oops_limit logic in sync with warn_limit,
+have oops_limit == 0 disable checking the Oops counter.
+
+Cc: Jann Horn <jannh@google.com>
+Cc: Jonathan Corbet <corbet@lwn.net>
+Cc: Andrew Morton <akpm@linux-foundation.org>
+Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
+Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
+Cc: Eric Biggers <ebiggers@google.com>
+Cc: Huang Ying <ying.huang@intel.com>
+Cc: "Eric W. Biederman" <ebiederm@xmission.com>
+Cc: Arnd Bergmann <arnd@arndb.de>
+Cc: linux-doc@vger.kernel.org
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ Documentation/sysctl/kernel.txt | 5 +++--
+ kernel/exit.c | 2 +-
+ 2 files changed, 4 insertions(+), 3 deletions(-)
+
+--- a/Documentation/sysctl/kernel.txt
++++ b/Documentation/sysctl/kernel.txt
+@@ -519,8 +519,9 @@ scanned for a given scan.
+ oops_limit:
+
+ Number of kernel oopses after which the kernel should panic when
+-``panic_on_oops`` is not set. Setting this to 0 or 1 has the same effect
+-as setting ``panic_on_oops=1``.
++``panic_on_oops`` is not set. Setting this to 0 disables checking
++the count. Setting this to 1 has the same effect as setting
++``panic_on_oops=1``. The default value is 10000.
+
+ ==============================================================
+
+--- a/kernel/exit.c
++++ b/kernel/exit.c
+@@ -984,7 +984,7 @@ void __noreturn make_task_dead(int signr
+ * To make sure this can't happen, place an upper bound on how often the
+ * kernel may oops without panic().
+ */
+- if (atomic_inc_return(&oops_count) >= READ_ONCE(oops_limit))
++ if (atomic_inc_return(&oops_count) >= READ_ONCE(oops_limit) && oops_limit)
+ panic("Oopsed too often (kernel.oops_limit is %d)", oops_limit);
+
+ do_exit(signr);
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:55 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:48 -0800
+Subject: exit: Expose "oops_count" to sysfs
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>, Luis Chamberlain <mcgrof@kernel.org>
+Message-ID: <20230203003354.85691-10-ebiggers@kernel.org>
+
+From: Kees Cook <keescook@chromium.org>
+
+commit 9db89b41117024f80b38b15954017fb293133364 upstream.
+
+Since Oops count is now tracked and is a fairly interesting signal, add
+the entry /sys/kernel/oops_count to expose it to userspace.
+
+Cc: "Eric W. Biederman" <ebiederm@xmission.com>
+Cc: Jann Horn <jannh@google.com>
+Cc: Arnd Bergmann <arnd@arndb.de>
+Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Link: https://lore.kernel.org/r/20221117234328.594699-3-keescook@chromium.org
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ Documentation/ABI/testing/sysfs-kernel-oops_count | 6 ++++++
+ kernel/exit.c | 22 ++++++++++++++++++++--
+ 2 files changed, 26 insertions(+), 2 deletions(-)
+ create mode 100644 Documentation/ABI/testing/sysfs-kernel-oops_count
+
+--- /dev/null
++++ b/Documentation/ABI/testing/sysfs-kernel-oops_count
+@@ -0,0 +1,6 @@
++What: /sys/kernel/oops_count
++Date: November 2022
++KernelVersion: 6.2.0
++Contact: Linux Kernel Hardening List <linux-hardening@vger.kernel.org>
++Description:
++ Shows how many times the system has Oopsed since last boot.
+--- a/kernel/exit.c
++++ b/kernel/exit.c
+@@ -62,6 +62,7 @@
+ #include <linux/random.h>
+ #include <linux/rcuwait.h>
+ #include <linux/compat.h>
++#include <linux/sysfs.h>
+
+ #include <linux/uaccess.h>
+ #include <asm/unistd.h>
+@@ -95,6 +96,25 @@ static __init int kernel_exit_sysctls_in
+ late_initcall(kernel_exit_sysctls_init);
+ #endif
+
++static atomic_t oops_count = ATOMIC_INIT(0);
++
++#ifdef CONFIG_SYSFS
++static ssize_t oops_count_show(struct kobject *kobj, struct kobj_attribute *attr,
++ char *page)
++{
++ return sysfs_emit(page, "%d\n", atomic_read(&oops_count));
++}
++
++static struct kobj_attribute oops_count_attr = __ATTR_RO(oops_count);
++
++static __init int kernel_exit_sysfs_init(void)
++{
++ sysfs_add_file_to_group(kernel_kobj, &oops_count_attr.attr, NULL);
++ return 0;
++}
++late_initcall(kernel_exit_sysfs_init);
++#endif
++
+ static void __unhash_process(struct task_struct *p, bool group_dead)
+ {
+ nr_threads--;
+@@ -949,8 +969,6 @@ EXPORT_SYMBOL_GPL(do_exit);
+
+ void __noreturn make_task_dead(int signr)
+ {
+- static atomic_t oops_count = ATOMIC_INIT(0);
+-
+ /*
+ * Take the task off the cpu after something catastrophic has
+ * happened.
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:50 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:47 -0800
+Subject: exit: Put an upper limit on how often we can oops
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Luis Chamberlain <mcgrof@kernel.org>
+Message-ID: <20230203003354.85691-9-ebiggers@kernel.org>
+
+From: Jann Horn <jannh@google.com>
+
+commit d4ccd54d28d3c8598e2354acc13e28c060961dbb upstream.
+
+Many Linux systems are configured to not panic on oops; but allowing an
+attacker to oops the system **really** often can make even bugs that look
+completely unexploitable exploitable (like NULL dereferences and such) if
+each crash elevates a refcount by one or a lock is taken in read mode, and
+this causes a counter to eventually overflow.
+
+The most interesting counters for this are 32 bits wide (like open-coded
+refcounts that don't use refcount_t). (The ldsem reader count on 32-bit
+platforms is just 16 bits, but probably nobody cares about 32-bit platforms
+that much nowadays.)
+
+So let's panic the system if the kernel is constantly oopsing.
+
+The speed of oopsing 2^32 times probably depends on several factors, like
+how long the stack trace is and which unwinder you're using; an empirically
+important one is whether your console is showing a graphical environment or
+a text console that oopses will be printed to.
+In a quick single-threaded benchmark, it looks like oopsing in a vfork()
+child with a very short stack trace only takes ~510 microseconds per run
+when a graphical console is active; but switching to a text console that
+oopses are printed to slows it down around 87x, to ~45 milliseconds per
+run.
+(Adding more threads makes this faster, but the actual oops printing
+happens under &die_lock on x86, so you can maybe speed this up by a factor
+of around 2 and then any further improvement gets eaten up by lock
+contention.)
+
+It looks like it would take around 8-12 days to overflow a 32-bit counter
+with repeated oopsing on a multi-core X86 system running a graphical
+environment; both me (in an X86 VM) and Seth (with a distro kernel on
+normal hardware in a standard configuration) got numbers in that ballpark.
+
+12 days aren't *that* short on a desktop system, and you'd likely need much
+longer on a typical server system (assuming that people don't run graphical
+desktop environments on their servers), and this is a *very* noisy and
+violent approach to exploiting the kernel; and it also seems to take orders
+of magnitude longer on some machines, probably because stuff like EFI
+pstore will slow it down a ton if that's active.
+
+Signed-off-by: Jann Horn <jannh@google.com>
+Link: https://lore.kernel.org/r/20221107201317.324457-1-jannh@google.com
+Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Link: https://lore.kernel.org/r/20221117234328.594699-2-keescook@chromium.org
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ Documentation/sysctl/kernel.txt | 9 ++++++++
+ kernel/exit.c | 43 ++++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 52 insertions(+)
+
+--- a/Documentation/sysctl/kernel.txt
++++ b/Documentation/sysctl/kernel.txt
+@@ -48,6 +48,7 @@ show up in /proc/sys/kernel:
+ - msgmnb
+ - msgmni
+ - nmi_watchdog
++- oops_limit
+ - osrelease
+ - ostype
+ - overflowgid
+@@ -515,6 +516,14 @@ scanned for a given scan.
+
+ ==============================================================
+
++oops_limit:
++
++Number of kernel oopses after which the kernel should panic when
++``panic_on_oops`` is not set. Setting this to 0 or 1 has the same effect
++as setting ``panic_on_oops=1``.
++
++==============================================================
++
+ osrelease, ostype & version:
+
+ # cat osrelease
+--- a/kernel/exit.c
++++ b/kernel/exit.c
+@@ -68,6 +68,33 @@
+ #include <asm/pgtable.h>
+ #include <asm/mmu_context.h>
+
++/*
++ * The default value should be high enough to not crash a system that randomly
++ * crashes its kernel from time to time, but low enough to at least not permit
++ * overflowing 32-bit refcounts or the ldsem writer count.
++ */
++static unsigned int oops_limit = 10000;
++
++#ifdef CONFIG_SYSCTL
++static struct ctl_table kern_exit_table[] = {
++ {
++ .procname = "oops_limit",
++ .data = &oops_limit,
++ .maxlen = sizeof(oops_limit),
++ .mode = 0644,
++ .proc_handler = proc_douintvec,
++ },
++ { }
++};
++
++static __init int kernel_exit_sysctls_init(void)
++{
++ register_sysctl_init("kernel", kern_exit_table);
++ return 0;
++}
++late_initcall(kernel_exit_sysctls_init);
++#endif
++
+ static void __unhash_process(struct task_struct *p, bool group_dead)
+ {
+ nr_threads--;
+@@ -922,10 +949,26 @@ EXPORT_SYMBOL_GPL(do_exit);
+
+ void __noreturn make_task_dead(int signr)
+ {
++ static atomic_t oops_count = ATOMIC_INIT(0);
++
+ /*
+ * Take the task off the cpu after something catastrophic has
+ * happened.
+ */
++
++ /*
++ * Every time the system oopses, if the oops happens while a reference
++ * to an object was held, the reference leaks.
++ * If the oops doesn't also leak memory, repeated oopsing can cause
++ * reference counters to wrap around (if they're not using refcount_t).
++ * This means that repeated oopsing can make unexploitable-looking bugs
++ * exploitable through repeated oopsing.
++ * To make sure this can't happen, place an upper bound on how often the
++ * kernel may oops without panic().
++ */
++ if (atomic_inc_return(&oops_count) >= READ_ONCE(oops_limit))
++ panic("Oopsed too often (kernel.oops_limit is %d)", oops_limit);
++
+ do_exit(signr);
+ }
+
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:46 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:54 -0800
+Subject: exit: Use READ_ONCE() for all oops/warn limit reads
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>, Petr Mladek <pmladek@suse.com>, Andrew Morton <akpm@linux-foundation.org>, Luis Chamberlain <mcgrof@kernel.org>, Marco Elver <elver@google.com>, tangmeng <tangmeng@uniontech.com>, Sebastian Andrzej Siewior <bigeasy@linutronix.de>, Tiezhu Yang <yangtiezhu@loongson.cn>, Peter Zijlstra <peterz@infradead.org>
+Message-ID: <20230203003354.85691-16-ebiggers@kernel.org>
+
+From: Kees Cook <keescook@chromium.org>
+
+commit 7535b832c6399b5ebfc5b53af5c51dd915ee2538 upstream.
+
+Use a temporary variable to take full advantage of READ_ONCE() behavior.
+Without this, the report (and even the test) might be out of sync with
+the initial test.
+
+Reported-by: Peter Zijlstra <peterz@infradead.org>
+Link: https://lore.kernel.org/lkml/Y5x7GXeluFmZ8E0E@hirez.programming.kicks-ass.net
+Fixes: 9fc9e278a5c0 ("panic: Introduce warn_limit")
+Fixes: d4ccd54d28d3 ("exit: Put an upper limit on how often we can oops")
+Cc: "Eric W. Biederman" <ebiederm@xmission.com>
+Cc: Jann Horn <jannh@google.com>
+Cc: Arnd Bergmann <arnd@arndb.de>
+Cc: Petr Mladek <pmladek@suse.com>
+Cc: Andrew Morton <akpm@linux-foundation.org>
+Cc: Luis Chamberlain <mcgrof@kernel.org>
+Cc: Marco Elver <elver@google.com>
+Cc: tangmeng <tangmeng@uniontech.com>
+Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/exit.c | 6 ++++--
+ kernel/panic.c | 7 +++++--
+ 2 files changed, 9 insertions(+), 4 deletions(-)
+
+--- a/kernel/exit.c
++++ b/kernel/exit.c
+@@ -973,6 +973,7 @@ void __noreturn make_task_dead(int signr
+ * Take the task off the cpu after something catastrophic has
+ * happened.
+ */
++ unsigned int limit;
+
+ /*
+ * Every time the system oopses, if the oops happens while a reference
+@@ -984,8 +985,9 @@ void __noreturn make_task_dead(int signr
+ * To make sure this can't happen, place an upper bound on how often the
+ * kernel may oops without panic().
+ */
+- if (atomic_inc_return(&oops_count) >= READ_ONCE(oops_limit) && oops_limit)
+- panic("Oopsed too often (kernel.oops_limit is %d)", oops_limit);
++ limit = READ_ONCE(oops_limit);
++ if (atomic_inc_return(&oops_count) >= limit && limit)
++ panic("Oopsed too often (kernel.oops_limit is %d)", limit);
+
+ do_exit(signr);
+ }
+--- a/kernel/panic.c
++++ b/kernel/panic.c
+@@ -165,12 +165,15 @@ EXPORT_SYMBOL(nmi_panic);
+
+ void check_panic_on_warn(const char *origin)
+ {
++ unsigned int limit;
++
+ if (panic_on_warn)
+ panic("%s: panic_on_warn set ...\n", origin);
+
+- if (atomic_inc_return(&warn_count) >= READ_ONCE(warn_limit) && warn_limit)
++ limit = READ_ONCE(warn_limit);
++ if (atomic_inc_return(&warn_count) >= limit && limit)
+ panic("%s: system warned too often (kernel.warn_limit is %d)",
+- origin, warn_limit);
++ origin, limit);
+ }
+
+ /**
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:40 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:45 -0800
+Subject: h8300: Fix build errors from do_exit() to make_task_dead() transition
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Nathan Chancellor <nathan@kernel.org>
+Message-ID: <20230203003354.85691-7-ebiggers@kernel.org>
+
+From: Nathan Chancellor <nathan@kernel.org>
+
+commit ab4ababdf77ccc56c7301c751dff49c79709c51c upstream.
+
+When building ARCH=h8300 defconfig:
+
+arch/h8300/kernel/traps.c: In function 'die':
+arch/h8300/kernel/traps.c:109:2: error: implicit declaration of function
+'make_dead_task' [-Werror=implicit-function-declaration]
+ 109 | make_dead_task(SIGSEGV);
+ | ^~~~~~~~~~~~~~
+
+arch/h8300/mm/fault.c: In function 'do_page_fault':
+arch/h8300/mm/fault.c:54:2: error: implicit declaration of function
+'make_dead_task' [-Werror=implicit-function-declaration]
+ 54 | make_dead_task(SIGKILL);
+ | ^~~~~~~~~~~~~~
+
+The function's name is make_task_dead(), change it so there is no more
+build error.
+
+Additionally, include linux/sched/task.h in arch/h8300/kernel/traps.c
+to avoid the same error because do_exit()'s declaration is in kernel.h
+but make_task_dead()'s is in task.h, which is not included in traps.c.
+
+Fixes: 0e25498f8cd4 ("exit: Add and use make_task_dead.")
+Signed-off-by: Nathan Chancellor <nathan@kernel.org>
+Link: https://lkml.kernel.org/r/20211227184851.2297759-3-nathan@kernel.org
+Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/h8300/kernel/traps.c | 3 ++-
+ arch/h8300/mm/fault.c | 2 +-
+ 2 files changed, 3 insertions(+), 2 deletions(-)
+
+--- a/arch/h8300/kernel/traps.c
++++ b/arch/h8300/kernel/traps.c
+@@ -17,6 +17,7 @@
+ #include <linux/types.h>
+ #include <linux/sched.h>
+ #include <linux/sched/debug.h>
++#include <linux/sched/task.h>
+ #include <linux/mm_types.h>
+ #include <linux/kernel.h>
+ #include <linux/errno.h>
+@@ -110,7 +111,7 @@ void die(const char *str, struct pt_regs
+ dump(fp);
+
+ spin_unlock_irq(&die_lock);
+- make_dead_task(SIGSEGV);
++ make_task_dead(SIGSEGV);
+ }
+
+ static int kstack_depth_to_print = 24;
+--- a/arch/h8300/mm/fault.c
++++ b/arch/h8300/mm/fault.c
+@@ -52,7 +52,7 @@ asmlinkage int do_page_fault(struct pt_r
+ printk(" at virtual address %08lx\n", address);
+ if (!user_mode(regs))
+ die("Oops", regs, error_code);
+- make_dead_task(SIGKILL);
++ make_task_dead(SIGKILL);
+
+ return 1;
+ }
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:40 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:44 -0800
+Subject: hexagon: Fix function name in die()
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Nathan Chancellor <nathan@kernel.org>
+Message-ID: <20230203003354.85691-6-ebiggers@kernel.org>
+
+From: Nathan Chancellor <nathan@kernel.org>
+
+commit 4f0712ccec09c071e221242a2db9a6779a55a949 upstream.
+
+When building ARCH=hexagon defconfig:
+
+arch/hexagon/kernel/traps.c:217:2: error: implicit declaration of
+function 'make_dead_task' [-Werror,-Wimplicit-function-declaration]
+ make_dead_task(err);
+ ^
+
+The function's name is make_task_dead(), change it so there is no more
+build error.
+
+Fixes: 0e25498f8cd4 ("exit: Add and use make_task_dead.")
+Signed-off-by: Nathan Chancellor <nathan@kernel.org>
+Link: https://lkml.kernel.org/r/20211227184851.2297759-2-nathan@kernel.org
+Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/hexagon/kernel/traps.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/arch/hexagon/kernel/traps.c
++++ b/arch/hexagon/kernel/traps.c
+@@ -234,7 +234,7 @@ int die(const char *str, struct pt_regs
+ panic("Fatal exception");
+
+ oops_exit();
+- make_dead_task(err);
++ make_task_dead(err);
+ return 0;
+ }
+
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:45 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:46 -0800
+Subject: ia64: make IA64_MCA_RECOVERY bool instead of tristate
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Tony Luck <tony.luck@intel.com>, Randy Dunlap <rdunlap@infradead.org>, Christoph Hellwig <hch@infradead.org>, Christoph Hellwig <hch@lst.de>, Andrew Morton <akpm@linux-foundation.org>, Linus Torvalds <torvalds@linux-foundation.org>
+Message-ID: <20230203003354.85691-8-ebiggers@kernel.org>
+
+From: Randy Dunlap <rdunlap@infradead.org>
+
+commit dbecf9b8b8ce580f4e11afed9d61e8aa294cddd2 upstream.
+
+In linux-next, IA64_MCA_RECOVERY uses the (new) function
+make_task_dead(), which is not exported for use by modules. Instead of
+exporting it for one user, convert IA64_MCA_RECOVERY to be a bool
+Kconfig symbol.
+
+In a config file from "kernel test robot <lkp@intel.com>" for a
+different problem, this linker error was exposed when
+CONFIG_IA64_MCA_RECOVERY=m.
+
+Fixes this build error:
+
+ ERROR: modpost: "make_task_dead" [arch/ia64/kernel/mca_recovery.ko] undefined!
+
+Link: https://lkml.kernel.org/r/20220124213129.29306-1-rdunlap@infradead.org
+Fixes: 0e25498f8cd4 ("exit: Add and use make_task_dead.")
+Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
+Suggested-by: Christoph Hellwig <hch@infradead.org>
+Reviewed-by: Christoph Hellwig <hch@lst.de>
+Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
+Cc: Tony Luck <tony.luck@intel.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/ia64/Kconfig | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/arch/ia64/Kconfig
++++ b/arch/ia64/Kconfig
+@@ -461,7 +461,7 @@ config ARCH_PROC_KCORE_TEXT
+ depends on PROC_KCORE
+
+ config IA64_MCA_RECOVERY
+- tristate "MCA recovery from errors other than TLB."
++ bool "MCA recovery from errors other than TLB."
+
+ config PERFMON
+ bool "Performance monitor support"
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:40 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:43 -0800
+Subject: objtool: Add a missing comma to avoid string concatenation
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, kernel test robot <lkp@intel.com>
+Message-ID: <20230203003354.85691-5-ebiggers@kernel.org>
+
+From: "Eric W. Biederman" <ebiederm@xmission.com>
+
+commit 1fb466dff904e4a72282af336f2c355f011eec61 upstream.
+
+Recently the kbuild robot reported two new errors:
+
+>> lib/kunit/kunit-example-test.o: warning: objtool: .text.unlikely: unexpected end of section
+>> arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_opcodes()
+
+I don't know why they did not occur in my test setup but after digging
+it I realized I had accidentally dropped a comma in
+tools/objtool/check.c when I renamed rewind_stack_do_exit to
+rewind_stack_and_make_dead.
+
+Add that comma back to fix objtool errors.
+
+Link: https://lkml.kernel.org/r/202112140949.Uq5sFKR1-lkp@intel.com
+Fixes: 0e25498f8cd4 ("exit: Add and use make_task_dead.")
+Reported-by: kernel test robot <lkp@intel.com>
+Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ tools/objtool/check.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/tools/objtool/check.c
++++ b/tools/objtool/check.c
+@@ -167,7 +167,7 @@ static int __dead_end_function(struct ob
+ "lbug_with_loc",
+ "fortify_panic",
+ "machine_real_restart",
+- "rewind_stack_and_make_dead"
++ "rewind_stack_and_make_dead",
+ };
+
+ if (func->bind == STB_WEAK)
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:49 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:50 -0800
+Subject: panic: Consolidate open-coded panic_on_warn checks
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Marco Elver <elver@google.com>, Dmitry Vyukov <dvyukov@google.com>, Ingo Molnar <mingo@redhat.com>, Peter Zijlstra <peterz@infradead.org>, Juri Lelli <juri.lelli@redhat.com>, Vincent Guittot <vincent.guittot@linaro.org>, Dietmar Eggemann <dietmar.eggemann@arm.com>, Steven Rostedt <rostedt@goodmis.org>, Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>, Daniel Bristot de Oliveira <bristot@redhat.com>, Valentin Schneider <vschneid@redhat.com>, Andrey Ryabinin <ryabinin.a.a@gmail.com>, Alexander Potapenko <glider@google.com>, Andrey Konovalov <andreyknvl@gmail.com>, Vincenzo Frascino <vincenzo.frascino@arm.com>, Andrew Morton <akpm@linux-foundation.org>, David Gow <davidgow@google.com>, tangmeng <tangmeng@uniontech.com>, Shuah Khan <skhan@linuxfoundation.org>, Petr Mladek <pmladek@suse.com>, "Paul E. McKenney" <paulmck@kernel.org>, Sebastian Andrzej Siewior <bigeasy@linutronix.de>, "Guilherme G. Piccoli" <gpiccoli@igalia.com>, Tiezhu Yang <yangtiezhu@loongson.cn>, kasan-dev@googlegroups.com, linux-mm@kvack.org, Luis Chamberlain <mcgrof@kernel.org>
+Message-ID: <20230203003354.85691-12-ebiggers@kernel.org>
+
+From: Kees Cook <keescook@chromium.org>
+
+commit 79cc1ba7badf9e7a12af99695a557e9ce27ee967 upstream.
+
+Several run-time checkers (KASAN, UBSAN, KFENCE, KCSAN, sched) roll
+their own warnings, and each check "panic_on_warn". Consolidate this
+into a single function so that future instrumentation can be added in
+a single location.
+
+Cc: Marco Elver <elver@google.com>
+Cc: Dmitry Vyukov <dvyukov@google.com>
+Cc: Ingo Molnar <mingo@redhat.com>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Cc: Juri Lelli <juri.lelli@redhat.com>
+Cc: Vincent Guittot <vincent.guittot@linaro.org>
+Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
+Cc: Steven Rostedt <rostedt@goodmis.org>
+Cc: Ben Segall <bsegall@google.com>
+Cc: Mel Gorman <mgorman@suse.de>
+Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
+Cc: Valentin Schneider <vschneid@redhat.com>
+Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
+Cc: Alexander Potapenko <glider@google.com>
+Cc: Andrey Konovalov <andreyknvl@gmail.com>
+Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
+Cc: Andrew Morton <akpm@linux-foundation.org>
+Cc: David Gow <davidgow@google.com>
+Cc: tangmeng <tangmeng@uniontech.com>
+Cc: Jann Horn <jannh@google.com>
+Cc: Shuah Khan <skhan@linuxfoundation.org>
+Cc: Petr Mladek <pmladek@suse.com>
+Cc: "Paul E. McKenney" <paulmck@kernel.org>
+Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
+Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
+Cc: kasan-dev@googlegroups.com
+Cc: linux-mm@kvack.org
+Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Reviewed-by: Marco Elver <elver@google.com>
+Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
+Link: https://lore.kernel.org/r/20221117234328.594699-4-keescook@chromium.org
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/linux/kernel.h | 1 +
+ kernel/panic.c | 9 +++++++--
+ kernel/sched/core.c | 3 +--
+ mm/kasan/report.c | 3 +--
+ 4 files changed, 10 insertions(+), 6 deletions(-)
+
+--- a/include/linux/kernel.h
++++ b/include/linux/kernel.h
+@@ -293,6 +293,7 @@ extern long (*panic_blink)(int state);
+ __printf(1, 2)
+ void panic(const char *fmt, ...) __noreturn __cold;
+ void nmi_panic(struct pt_regs *regs, const char *msg);
++void check_panic_on_warn(const char *origin);
+ extern void oops_enter(void);
+ extern void oops_exit(void);
+ void print_oops_end_marker(void);
+--- a/kernel/panic.c
++++ b/kernel/panic.c
+@@ -122,6 +122,12 @@ void nmi_panic(struct pt_regs *regs, con
+ }
+ EXPORT_SYMBOL(nmi_panic);
+
++void check_panic_on_warn(const char *origin)
++{
++ if (panic_on_warn)
++ panic("%s: panic_on_warn set ...\n", origin);
++}
++
+ /**
+ * panic - halt the system
+ * @fmt: The text string to print
+@@ -546,8 +552,7 @@ void __warn(const char *file, int line,
+ if (args)
+ vprintk(args->fmt, args->args);
+
+- if (panic_on_warn)
+- panic("panic_on_warn set ...\n");
++ check_panic_on_warn("kernel");
+
+ print_modules();
+
+--- a/kernel/sched/core.c
++++ b/kernel/sched/core.c
+@@ -3185,8 +3185,7 @@ static noinline void __schedule_bug(stru
+ print_ip_sym(preempt_disable_ip);
+ pr_cont("\n");
+ }
+- if (panic_on_warn)
+- panic("scheduling while atomic\n");
++ check_panic_on_warn("scheduling while atomic");
+
+ dump_stack();
+ add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
+--- a/mm/kasan/report.c
++++ b/mm/kasan/report.c
+@@ -172,8 +172,7 @@ static void kasan_end_report(unsigned lo
+ pr_err("==================================================================\n");
+ add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
+ spin_unlock_irqrestore(&report_lock, *flags);
+- if (panic_on_warn)
+- panic("panic_on_warn set ...\n");
++ check_panic_on_warn("KASAN");
+ kasan_enable_current();
+ }
+
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:46 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:52 -0800
+Subject: panic: Expose "warn_count" to sysfs
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Petr Mladek <pmladek@suse.com>, Andrew Morton <akpm@linux-foundation.org>, tangmeng <tangmeng@uniontech.com>, "Guilherme G. Piccoli" <gpiccoli@igalia.com>, Sebastian Andrzej Siewior <bigeasy@linutronix.de>, Tiezhu Yang <yangtiezhu@loongson.cn>, Luis Chamberlain <mcgrof@kernel.org>
+Message-ID: <20230203003354.85691-14-ebiggers@kernel.org>
+
+From: Kees Cook <keescook@chromium.org>
+
+commit 8b05aa26336113c4cea25f1c333ee8cd4fc212a6 upstream.
+
+Since Warn count is now tracked and is a fairly interesting signal, add
+the entry /sys/kernel/warn_count to expose it to userspace.
+
+Cc: Petr Mladek <pmladek@suse.com>
+Cc: Andrew Morton <akpm@linux-foundation.org>
+Cc: tangmeng <tangmeng@uniontech.com>
+Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
+Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
+Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Link: https://lore.kernel.org/r/20221117234328.594699-6-keescook@chromium.org
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ Documentation/ABI/testing/sysfs-kernel-warn_count | 6 ++++++
+ kernel/panic.c | 22 ++++++++++++++++++++--
+ 2 files changed, 26 insertions(+), 2 deletions(-)
+ create mode 100644 Documentation/ABI/testing/sysfs-kernel-warn_count
+
+--- /dev/null
++++ b/Documentation/ABI/testing/sysfs-kernel-warn_count
+@@ -0,0 +1,6 @@
++What: /sys/kernel/oops_count
++Date: November 2022
++KernelVersion: 6.2.0
++Contact: Linux Kernel Hardening List <linux-hardening@vger.kernel.org>
++Description:
++ Shows how many times the system has Warned since last boot.
+--- a/kernel/panic.c
++++ b/kernel/panic.c
+@@ -28,6 +28,7 @@
+ #include <linux/console.h>
+ #include <linux/bug.h>
+ #include <linux/ratelimit.h>
++#include <linux/sysfs.h>
+
+ #define PANIC_TIMER_STEP 100
+ #define PANIC_BLINK_SPD 18
+@@ -68,6 +69,25 @@ static __init int kernel_panic_sysctls_i
+ late_initcall(kernel_panic_sysctls_init);
+ #endif
+
++static atomic_t warn_count = ATOMIC_INIT(0);
++
++#ifdef CONFIG_SYSFS
++static ssize_t warn_count_show(struct kobject *kobj, struct kobj_attribute *attr,
++ char *page)
++{
++ return sysfs_emit(page, "%d\n", atomic_read(&warn_count));
++}
++
++static struct kobj_attribute warn_count_attr = __ATTR_RO(warn_count);
++
++static __init int kernel_panic_sysfs_init(void)
++{
++ sysfs_add_file_to_group(kernel_kobj, &warn_count_attr.attr, NULL);
++ return 0;
++}
++late_initcall(kernel_panic_sysfs_init);
++#endif
++
+ static long no_blink(int state)
+ {
+ return 0;
+@@ -145,8 +165,6 @@ EXPORT_SYMBOL(nmi_panic);
+
+ void check_panic_on_warn(const char *origin)
+ {
+- static atomic_t warn_count = ATOMIC_INIT(0);
+-
+ if (panic_on_warn)
+ panic("%s: panic_on_warn set ...\n", origin);
+
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:49 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:51 -0800
+Subject: panic: Introduce warn_limit
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>, Andrew Morton <akpm@linux-foundation.org>, Baolin Wang <baolin.wang@linux.alibaba.com>, "Jason A. Donenfeld" <Jason@zx2c4.com>, Eric Biggers <ebiggers@google.com>, Huang Ying <ying.huang@intel.com>, Petr Mladek <pmladek@suse.com>, tangmeng <tangmeng@uniontech.com>, "Guilherme G. Piccoli" <gpiccoli@igalia.com>, Tiezhu Yang <yangtiezhu@loongson.cn>, Sebastian Andrzej Siewior <bigeasy@linutronix.de>, linux-doc@vger.kernel.org, Luis Chamberlain <mcgrof@kernel.org>
+Message-ID: <20230203003354.85691-13-ebiggers@kernel.org>
+
+From: Kees Cook <keescook@chromium.org>
+
+commit 9fc9e278a5c0b708eeffaf47d6eb0c82aa74ed78 upstream.
+
+Like oops_limit, add warn_limit for limiting the number of warnings when
+panic_on_warn is not set.
+
+Cc: Jonathan Corbet <corbet@lwn.net>
+Cc: Andrew Morton <akpm@linux-foundation.org>
+Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
+Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
+Cc: Eric Biggers <ebiggers@google.com>
+Cc: Huang Ying <ying.huang@intel.com>
+Cc: Petr Mladek <pmladek@suse.com>
+Cc: tangmeng <tangmeng@uniontech.com>
+Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
+Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
+Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Cc: linux-doc@vger.kernel.org
+Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Link: https://lore.kernel.org/r/20221117234328.594699-5-keescook@chromium.org
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ Documentation/sysctl/kernel.txt | 10 ++++++++++
+ kernel/panic.c | 27 +++++++++++++++++++++++++++
+ 2 files changed, 37 insertions(+)
+
+--- a/Documentation/sysctl/kernel.txt
++++ b/Documentation/sysctl/kernel.txt
+@@ -94,6 +94,7 @@ show up in /proc/sys/kernel:
+ - threads-max
+ - unprivileged_bpf_disabled
+ - unknown_nmi_panic
++- warn_limit
+ - watchdog
+ - watchdog_thresh
+ - version
+@@ -1072,6 +1073,15 @@ example. If a system hangs up, try pres
+
+ ==============================================================
+
++warn_limit:
++
++Number of kernel warnings after which the kernel should panic when
++``panic_on_warn`` is not set. Setting this to 0 disables checking
++the warning count. Setting this to 1 has the same effect as setting
++``panic_on_warn=1``. The default value is 0.
++
++==============================================================
++
+ watchdog:
+
+ This parameter can be used to disable or enable the soft lockup detector
+--- a/kernel/panic.c
++++ b/kernel/panic.c
+@@ -39,6 +39,7 @@ static int pause_on_oops_flag;
+ static DEFINE_SPINLOCK(pause_on_oops_lock);
+ bool crash_kexec_post_notifiers;
+ int panic_on_warn __read_mostly;
++static unsigned int warn_limit __read_mostly;
+
+ int panic_timeout = CONFIG_PANIC_TIMEOUT;
+ EXPORT_SYMBOL_GPL(panic_timeout);
+@@ -47,6 +48,26 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list
+
+ EXPORT_SYMBOL(panic_notifier_list);
+
++#ifdef CONFIG_SYSCTL
++static struct ctl_table kern_panic_table[] = {
++ {
++ .procname = "warn_limit",
++ .data = &warn_limit,
++ .maxlen = sizeof(warn_limit),
++ .mode = 0644,
++ .proc_handler = proc_douintvec,
++ },
++ { }
++};
++
++static __init int kernel_panic_sysctls_init(void)
++{
++ register_sysctl_init("kernel", kern_panic_table);
++ return 0;
++}
++late_initcall(kernel_panic_sysctls_init);
++#endif
++
+ static long no_blink(int state)
+ {
+ return 0;
+@@ -124,8 +145,14 @@ EXPORT_SYMBOL(nmi_panic);
+
+ void check_panic_on_warn(const char *origin)
+ {
++ static atomic_t warn_count = ATOMIC_INIT(0);
++
+ if (panic_on_warn)
+ panic("%s: panic_on_warn set ...\n", origin);
++
++ if (atomic_inc_return(&warn_count) >= READ_ONCE(warn_limit) && warn_limit)
++ panic("%s: system warned too often (kernel.warn_limit is %d)",
++ origin, warn_limit);
+ }
+
+ /**
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:38 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:41 -0800
+Subject: panic: unset panic_on_warn inside panic()
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Andrey Ryabinin <ryabinin.a.a@gmail.com>, Baoquan He <bhe@redhat.com>, Jonathan Corbet <corbet@lwn.net>, Xuefeng Li <lixuefeng@loongson.cn>, Tiezhu Yang <yangtiezhu@loongson.cn>, Marco Elver <elver@google.com>, Andrew Morton <akpm@linux-foundation.org>, Linus Torvalds <torvalds@linux-foundation.org>
+Message-ID: <20230203003354.85691-3-ebiggers@kernel.org>
+
+From: Tiezhu Yang <yangtiezhu@loongson.cn>
+
+commit 1a2383e8b84c0451fd9b1eec3b9aab16f30b597c upstream.
+
+In the current code, the following three places need to unset
+panic_on_warn before calling panic() to avoid recursive panics:
+
+kernel/kcsan/report.c: print_report()
+kernel/sched/core.c: __schedule_bug()
+mm/kfence/report.c: kfence_report_error()
+
+In order to avoid copy-pasting "panic_on_warn = 0" all over the places,
+it is better to move it inside panic() and then remove it from the other
+places.
+
+Link: https://lkml.kernel.org/r/1644324666-15947-4-git-send-email-yangtiezhu@loongson.cn
+Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
+Reviewed-by: Marco Elver <elver@google.com>
+Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
+Cc: Baoquan He <bhe@redhat.com>
+Cc: Jonathan Corbet <corbet@lwn.net>
+Cc: Xuefeng Li <lixuefeng@loongson.cn>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/panic.c | 20 +++++++++++---------
+ 1 file changed, 11 insertions(+), 9 deletions(-)
+
+--- a/kernel/panic.c
++++ b/kernel/panic.c
+@@ -139,6 +139,16 @@ void panic(const char *fmt, ...)
+ int old_cpu, this_cpu;
+ bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers;
+
++ if (panic_on_warn) {
++ /*
++ * This thread may hit another WARN() in the panic path.
++ * Resetting this prevents additional WARN() from panicking the
++ * system on this thread. Other threads are blocked by the
++ * panic_mutex in panic().
++ */
++ panic_on_warn = 0;
++ }
++
+ /*
+ * Disable local interrupts. This will prevent panic_smp_self_stop
+ * from deadlocking the first cpu that invokes the panic, since
+@@ -536,16 +546,8 @@ void __warn(const char *file, int line,
+ if (args)
+ vprintk(args->fmt, args->args);
+
+- if (panic_on_warn) {
+- /*
+- * This thread may hit another WARN() in the panic path.
+- * Resetting this prevents additional WARN() from panicking the
+- * system on this thread. Other threads are blocked by the
+- * panic_mutex in panic().
+- */
+- panic_on_warn = 0;
++ if (panic_on_warn)
+ panic("panic_on_warn set ...\n");
+- }
+
+ print_modules();
+
scsi-qla2xxx-don-t-break-the-bsg-lib-abstractions.patch
x86-asm-fix-an-assembler-warning-with-current-binutils.patch
x86-entry-64-add-instruction-suffix-to-sysret.patch
+sysctl-add-a-new-register_sysctl_init-interface.patch
+panic-unset-panic_on_warn-inside-panic.patch
+exit-add-and-use-make_task_dead.patch
+objtool-add-a-missing-comma-to-avoid-string-concatenation.patch
+hexagon-fix-function-name-in-die.patch
+h8300-fix-build-errors-from-do_exit-to-make_task_dead-transition.patch
+ia64-make-ia64_mca_recovery-bool-instead-of-tristate.patch
+exit-put-an-upper-limit-on-how-often-we-can-oops.patch
+exit-expose-oops_count-to-sysfs.patch
+exit-allow-oops_limit-to-be-disabled.patch
+panic-consolidate-open-coded-panic_on_warn-checks.patch
+panic-introduce-warn_limit.patch
+panic-expose-warn_count-to-sysfs.patch
+docs-fix-path-paste-o-for-sys-kernel-warn_count.patch
+exit-use-read_once-for-all-oops-warn-limit-reads.patch
--- /dev/null
+From stable-owner@vger.kernel.org Fri Feb 3 01:35:41 2023
+From: Eric Biggers <ebiggers@kernel.org>
+Date: Thu, 2 Feb 2023 16:33:40 -0800
+Subject: sysctl: add a new register_sysctl_init() interface
+To: stable@vger.kernel.org
+Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>, Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>, Seth Jenkins <sethjenkins@google.com>, Jann Horn <jannh@google.com>, "Eric W . Biederman" <ebiederm@xmission.com>, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, Iurii Zaikin <yzaikin@google.com>, Peter Zijlstra <peterz@infradead.org>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Paul Turner <pjt@google.com>, Andy Shevchenko <andriy.shevchenko@linux.intel.com>, Sebastian Reichel <sre@kernel.org>, Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>, Petr Mladek <pmladek@suse.com>, Sergey Senozhatsky <senozhatsky@chromium.org>, Qing Wang <wangqing@vivo.com>, Benjamin LaHaise <bcrl@kvack.org>, Al Viro <viro@zeniv.linux.org.uk>, Jan Kara <jack@suse.cz>, Amir Goldstein <amir73il@gmail.com>, Stephen Kitt <steve@sk2.org>, Antti Palosaari <crope@iki.fi>, Arnd Bergmann <arnd@arndb.de>, Benjamin Herrenschmidt <benh@kernel.crashing.org>, Clemens Ladisch <clemens@ladisch.de>, David Airlie <airlied@linux.ie>, Jani Nikula <jani.nikula@linux.intel.com>, Joel Becker <jlbec@evilplan.org>, Joonas Lahtinen <joonas.lahtinen@linux.intel.com>, Joseph Qi <joseph.qi@linux.alibaba.com>, Julia Lawall <julia.lawall@inria.fr>, Lukas Middendorf <kernel@tuxforce.de>, Mark Fasheh <mark@fasheh.com>, Phillip Potter <phil@philpotter.co.uk>, Rodrigo Vivi <rodrigo.vivi@intel.com>, Douglas Gilbert <dgilbert@interlog.com>, "James E . J . Bottomley" <jejb@linux.ibm.com>, Jani Nikula <jani.nikula@intel.com>, John Ogness <john.ogness@linutronix.de>, "Martin K . Petersen" <martin.petersen@oracle.com>, "Rafael J. Wysocki" <rafael@kernel.org>, Steven Rostedt <rostedt@goodmis.org>, Suren Baghdasaryan <surenb@google.com>, "Theodore Ts'o" <tytso@mit.edu>, Xiaoming Ni <nixiaoming@huawei.com>, Luis Chamberlain <mcgrof@kernel.org>, Andrew Morton <akpm@linux-foundation.org>, Linus Torvalds <torvalds@linux-foundation.org>
+Message-ID: <20230203003354.85691-2-ebiggers@kernel.org>
+
+From: Xiaoming Ni <nixiaoming@huawei.com>
+
+commit 3ddd9a808cee7284931312f2f3e854c9617f44b2 upstream.
+
+Patch series "sysctl: first set of kernel/sysctl cleanups", v2.
+
+Finally had time to respin the series of the work we had started last
+year on cleaning up the kernel/sysct.c kitchen sink. People keeps
+stuffing their sysctls in that file and this creates a maintenance
+burden. So this effort is aimed at placing sysctls where they actually
+belong.
+
+I'm going to split patches up into series as there is quite a bit of
+work.
+
+This first set adds register_sysctl_init() for uses of registerting a
+sysctl on the init path, adds const where missing to a few places,
+generalizes common values so to be more easy to share, and starts the
+move of a few kernel/sysctl.c out where they belong.
+
+The majority of rework on v2 in this first patch set is 0-day fixes.
+Eric Biederman's feedback is later addressed in subsequent patch sets.
+
+I'll only post the first two patch sets for now. We can address the
+rest once the first two patch sets get completely reviewed / Acked.
+
+This patch (of 9):
+
+The kernel/sysctl.c is a kitchen sink where everyone leaves their dirty
+dishes, this makes it very difficult to maintain.
+
+To help with this maintenance let's start by moving sysctls to places
+where they actually belong. The proc sysctl maintainers do not want to
+know what sysctl knobs you wish to add for your own piece of code, we
+just care about the core logic.
+
+Today though folks heavily rely on tables on kernel/sysctl.c so they can
+easily just extend this table with their needed sysctls. In order to
+help users move their sysctls out we need to provide a helper which can
+be used during code initialization.
+
+We special-case the initialization use of register_sysctl() since it
+*is* safe to fail, given all that sysctls do is provide a dynamic
+interface to query or modify at runtime an existing variable. So the
+use case of register_sysctl() on init should *not* stop if the sysctls
+don't end up getting registered. It would be counter productive to stop
+boot if a simple sysctl registration failed.
+
+Provide a helper for init then, and document the recommended init levels
+to use for callers of this routine. We will later use this in
+subsequent patches to start slimming down kernel/sysctl.c tables and
+moving sysctl registration to the code which actually needs these
+sysctls.
+
+[mcgrof@kernel.org: major commit log and documentation rephrasing also moved to fs/proc/proc_sysctl.c ]
+
+Link: https://lkml.kernel.org/r/20211123202347.818157-1-mcgrof@kernel.org
+Link: https://lkml.kernel.org/r/20211123202347.818157-2-mcgrof@kernel.org
+Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
+Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
+Reviewed-by: Kees Cook <keescook@chromium.org>
+Cc: Iurii Zaikin <yzaikin@google.com>
+Cc: "Eric W. Biederman" <ebiederm@xmission.com>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Cc: Paul Turner <pjt@google.com>
+Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+Cc: Sebastian Reichel <sre@kernel.org>
+Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
+Cc: Petr Mladek <pmladek@suse.com>
+Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
+Cc: Qing Wang <wangqing@vivo.com>
+Cc: Benjamin LaHaise <bcrl@kvack.org>
+Cc: Al Viro <viro@zeniv.linux.org.uk>
+Cc: Jan Kara <jack@suse.cz>
+Cc: Amir Goldstein <amir73il@gmail.com>
+Cc: Stephen Kitt <steve@sk2.org>
+Cc: Antti Palosaari <crope@iki.fi>
+Cc: Arnd Bergmann <arnd@arndb.de>
+Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
+Cc: Clemens Ladisch <clemens@ladisch.de>
+Cc: David Airlie <airlied@linux.ie>
+Cc: Jani Nikula <jani.nikula@linux.intel.com>
+Cc: Joel Becker <jlbec@evilplan.org>
+Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
+Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
+Cc: Julia Lawall <julia.lawall@inria.fr>
+Cc: Lukas Middendorf <kernel@tuxforce.de>
+Cc: Mark Fasheh <mark@fasheh.com>
+Cc: Phillip Potter <phil@philpotter.co.uk>
+Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
+Cc: Douglas Gilbert <dgilbert@interlog.com>
+Cc: James E.J. Bottomley <jejb@linux.ibm.com>
+Cc: Jani Nikula <jani.nikula@intel.com>
+Cc: John Ogness <john.ogness@linutronix.de>
+Cc: Martin K. Petersen <martin.petersen@oracle.com>
+Cc: "Rafael J. Wysocki" <rafael@kernel.org>
+Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
+Cc: Suren Baghdasaryan <surenb@google.com>
+Cc: "Theodore Ts'o" <tytso@mit.edu>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/proc/proc_sysctl.c | 33 +++++++++++++++++++++++++++++++++
+ include/linux/sysctl.h | 3 +++
+ 2 files changed, 36 insertions(+)
+
+--- a/fs/proc/proc_sysctl.c
++++ b/fs/proc/proc_sysctl.c
+@@ -13,6 +13,7 @@
+ #include <linux/namei.h>
+ #include <linux/mm.h>
+ #include <linux/module.h>
++#include <linux/kmemleak.h>
+ #include "internal.h"
+
+ static const struct dentry_operations proc_sys_dentry_operations;
+@@ -1370,6 +1371,38 @@ struct ctl_table_header *register_sysctl
+ }
+ EXPORT_SYMBOL(register_sysctl);
+
++/**
++ * __register_sysctl_init() - register sysctl table to path
++ * @path: path name for sysctl base
++ * @table: This is the sysctl table that needs to be registered to the path
++ * @table_name: The name of sysctl table, only used for log printing when
++ * registration fails
++ *
++ * The sysctl interface is used by userspace to query or modify at runtime
++ * a predefined value set on a variable. These variables however have default
++ * values pre-set. Code which depends on these variables will always work even
++ * if register_sysctl() fails. If register_sysctl() fails you'd just loose the
++ * ability to query or modify the sysctls dynamically at run time. Chances of
++ * register_sysctl() failing on init are extremely low, and so for both reasons
++ * this function does not return any error as it is used by initialization code.
++ *
++ * Context: Can only be called after your respective sysctl base path has been
++ * registered. So for instance, most base directories are registered early on
++ * init before init levels are processed through proc_sys_init() and
++ * sysctl_init().
++ */
++void __init __register_sysctl_init(const char *path, struct ctl_table *table,
++ const char *table_name)
++{
++ struct ctl_table_header *hdr = register_sysctl(path, table);
++
++ if (unlikely(!hdr)) {
++ pr_err("failed when register_sysctl %s to %s\n", table_name, path);
++ return;
++ }
++ kmemleak_not_leak(hdr);
++}
++
+ static char *append_path(const char *path, char *pos, const char *name)
+ {
+ int namelen;
+--- a/include/linux/sysctl.h
++++ b/include/linux/sysctl.h
+@@ -198,6 +198,9 @@ struct ctl_table_header *register_sysctl
+ void unregister_sysctl_table(struct ctl_table_header * table);
+
+ extern int sysctl_init(void);
++extern void __register_sysctl_init(const char *path, struct ctl_table *table,
++ const char *table_name);
++#define register_sysctl_init(path, table) __register_sysctl_init(path, table, #table)
+
+ extern struct ctl_table sysctl_mount_point[];
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
