Commit f71016a8 authored by Will Deacon's avatar Will Deacon
Browse files

arm64: signal: Call arm64_notify_segfault when failing to deliver signal 



If we fail to deliver a signal due to taking an unhandled fault on the
stackframe, we can call arm64_notify_segfault to deliver a SEGV can deal
with printing any unhandled signal messages for us, rather than roll our
own printing code.

A side-effect of this change is that we now deliver the frame address
in si_addr along with an si_code of SEGV_{ACC,MAP}ERR, rather than an
si_addr of 0 and an si_code of SI_KERNEL as before.

Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 92ff0674

arch/arm64/kernel/signal.c

+2 −5
Original line number Diff line number Diff line
@@ -40,6 +40,7 @@ 
#include <asm/fpsimd.h>

#include <asm/ptrace.h>

#include <asm/signal32.h>

#include <asm/traps.h>

#include <asm/vdso.h>



/*
@@ -565,11 +566,7 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs) 
	return regs->regs[0];



badframe:

	if (show_unhandled_signals)

		pr_info_ratelimited("%s[%d]: bad frame in %s: pc=%08llx sp=%08llx\n",

				    current->comm, task_pid_nr(current), __func__,

				    regs->pc, regs->sp);

	force_sig(SIGSEGV, current);

	arm64_notify_segfault(regs->sp);

	return 0;

}

arch/arm64/kernel/signal32.c

+3 −10
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <asm/esr.h>

#include <asm/fpsimd.h>

#include <asm/signal32.h>

#include <asm/traps.h>

#include <linux/uaccess.h>

#include <asm/unistd.h>
@@ -307,11 +308,7 @@ asmlinkage int compat_sys_sigreturn(struct pt_regs *regs) 
	return regs->regs[0];



badframe:

	if (show_unhandled_signals)

		pr_info_ratelimited("%s[%d]: bad frame in %s: pc=%08llx sp=%08llx\n",

				    current->comm, task_pid_nr(current), __func__,

				    regs->pc, regs->compat_sp);

	force_sig(SIGSEGV, current);

	arm64_notify_segfault(regs->compat_sp);

	return 0;

}
@@ -344,11 +341,7 @@ asmlinkage int compat_sys_rt_sigreturn(struct pt_regs *regs) 
	return regs->regs[0];



badframe:

	if (show_unhandled_signals)

		pr_info_ratelimited("%s[%d]: bad frame in %s: pc=%08llx sp=%08llx\n",

				    current->comm, task_pid_nr(current), __func__,

				    regs->pc, regs->compat_sp);

	force_sig(SIGSEGV, current);

	arm64_notify_segfault(regs->compat_sp);

	return 0;

}

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