[REVIEW][PATCH 07/20] signal/x86/traps: Factor out show_signal

From: Eric W. Biederman
Date: Mon Sep 17 2018 - 20:07:32 EST


The code for conditionally printing unhanded signals is duplicated twice
in arch/x86/kernel/traps.c. Factor it out into it's own subroutine
called show_signal to make the code clearer and easier to maintain.

Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
---
arch/x86/kernel/traps.c | 37 +++++++++++++++++++------------------
1 file changed, 19 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 2155d2c7f49b..31a689b67be3 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -217,6 +217,20 @@ do_trap_no_signal(struct task_struct *tsk, int trapnr, char *str,
return -1;
}

+static void show_signal(struct task_struct *tsk, int signr,
+ const char *type, const char *desc,
+ struct pt_regs *regs, long error_code)
+{
+ if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
+ printk_ratelimit()) {
+ pr_info("%s[%d] %s%s ip:%lx sp:%lx error:%lx",
+ tsk->comm, task_pid_nr(tsk), type, desc,
+ regs->ip, regs->sp, error_code);
+ print_vma_addr(KERN_CONT " in ", regs->ip);
+ pr_cont("\n");
+ }
+}
+
static siginfo_t *fill_trap_info(struct pt_regs *regs, int signr, int trapnr,
siginfo_t *info)
{
@@ -269,14 +283,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
tsk->thread.error_code = error_code;
tsk->thread.trap_nr = trapnr;

- if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
- printk_ratelimit()) {
- pr_info("%s[%d] trap %s ip:%lx sp:%lx error:%lx",
- tsk->comm, tsk->pid, str,
- regs->ip, regs->sp, error_code);
- print_vma_addr(KERN_CONT " in ", regs->ip);
- pr_cont("\n");
- }
+ show_signal(tsk, signr, "trap ", str, regs, error_code);

force_sig_info(signr, info ?: SEND_SIG_PRIV, tsk);
}
@@ -542,6 +549,7 @@ dotraplinkage void do_bounds(struct pt_regs *regs, long error_code)
dotraplinkage void
do_general_protection(struct pt_regs *regs, long error_code)
{
+ const char *desc = "general protection fault";
struct task_struct *tsk;

RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
@@ -565,23 +573,16 @@ do_general_protection(struct pt_regs *regs, long error_code)

tsk->thread.error_code = error_code;
tsk->thread.trap_nr = X86_TRAP_GP;
- if (notify_die(DIE_GPF, "general protection fault", regs, error_code,
+ if (notify_die(DIE_GPF, desc, regs, error_code,
X86_TRAP_GP, SIGSEGV) != NOTIFY_STOP)
- die("general protection fault", regs, error_code);
+ die(desc, regs, error_code);
return;
}

tsk->thread.error_code = error_code;
tsk->thread.trap_nr = X86_TRAP_GP;

- if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
- printk_ratelimit()) {
- pr_info("%s[%d] general protection ip:%lx sp:%lx error:%lx",
- tsk->comm, task_pid_nr(tsk),
- regs->ip, regs->sp, error_code);
- print_vma_addr(KERN_CONT " in ", regs->ip);
- pr_cont("\n");
- }
+ show_signal(tsk, SIGSEGV, "", desc, regs, error_code);

force_sig_info(SIGSEGV, SEND_SIG_PRIV, tsk);
}
--
2.17.1