From 3eb0f5193b497083391aa05d35210d5645211eef Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 17 Apr 2018 15:26:37 -0500 Subject: signal: Ensure every siginfo we send has all bits initialized 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" --- arch/parisc/kernel/ptrace.c | 1 + arch/parisc/kernel/traps.c | 2 ++ arch/parisc/kernel/unaligned.c | 1 + 3 files changed, 4 insertions(+) (limited to 'arch/parisc/kernel') diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c index 1a2be6e639b5..b1c12ceb1c88 100644 --- a/arch/parisc/kernel/ptrace.c +++ b/arch/parisc/kernel/ptrace.c @@ -90,6 +90,7 @@ void user_enable_single_step(struct task_struct *task) ptrace_disable(task); /* Don't wake up the task, but let the parent know something happened. */ + clear_siginfo(&si); si.si_code = TRAP_TRACE; si.si_addr = (void __user *) (task_regs(task)->iaoq[0] & ~3); si.si_signo = SIGTRAP; diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c index 68e671a11987..98f9f2f85940 100644 --- a/arch/parisc/kernel/traps.c +++ b/arch/parisc/kernel/traps.c @@ -299,6 +299,7 @@ static void handle_gdb_break(struct pt_regs *regs, int wot) { struct siginfo si; + clear_siginfo(&si); si.si_signo = SIGTRAP; si.si_errno = 0; si.si_code = wot; @@ -489,6 +490,7 @@ void notrace handle_interruption(int code, struct pt_regs *regs) unsigned long fault_space = 0; struct siginfo si; + clear_siginfo(&si); if (code == 1) pdc_console_restart(); /* switch back to pdc if HPMC */ else diff --git a/arch/parisc/kernel/unaligned.c b/arch/parisc/kernel/unaligned.c index e36f7b75ab07..30b7c7f6c471 100644 --- a/arch/parisc/kernel/unaligned.c +++ b/arch/parisc/kernel/unaligned.c @@ -455,6 +455,7 @@ void handle_unaligned(struct pt_regs *regs) struct siginfo si; register int flop=0; /* true if this is a flop */ + clear_siginfo(&si); __inc_irq_stat(irq_unaligned_count); /* log a message with pacing */ -- cgit v1.2.3