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/c6x/kernel/traps.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/c6x') diff --git a/arch/c6x/kernel/traps.c b/arch/c6x/kernel/traps.c index 4c1d4b84dd2b..c5feee4542b0 100644 --- a/arch/c6x/kernel/traps.c +++ b/arch/c6x/kernel/traps.c @@ -246,6 +246,7 @@ static void do_trap(struct exception_info *except_info, struct pt_regs *regs) unsigned long addr = instruction_pointer(regs); siginfo_t info; + clear_siginfo(&info); if (except_info->code != TRAP_BRKPT) pr_err("TRAP: %s PC[0x%lx] signo[%d] code[%d]\n", except_info->kernel_str, regs->pc, -- cgit v1.2.3 From 559f9008bbc56c2a561cd923709728af0cf659ac Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 1 Aug 2017 12:55:04 -0500 Subject: signal/c6x: Use force_sig_fault where appropriate Filling in struct siginfo before calling force_sig_info a tedious and error prone process, where once in a great while the wrong fields are filled out, and siginfo has been inconsistently cleared. Simplify this process by using the helper force_sig_fault. Which takes as a parameters all of the information it needs, ensures all of the fiddly bits of filling in struct siginfo are done properly and then calls force_sig_info. In short about a 5 line reduction in code for every time force_sig_info is called, which makes the calling function clearer. Cc: Mark Salter Cc: Aurelien Jacquiot Cc: linux-c6x-dev@linux-c6x.org Signed-off-by: "Eric W. Biederman" --- arch/c6x/kernel/traps.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) (limited to 'arch/c6x') diff --git a/arch/c6x/kernel/traps.c b/arch/c6x/kernel/traps.c index c5feee4542b0..5c60aea3b75a 100644 --- a/arch/c6x/kernel/traps.c +++ b/arch/c6x/kernel/traps.c @@ -244,9 +244,7 @@ static struct exception_info eexcept_table[128] = { static void do_trap(struct exception_info *except_info, struct pt_regs *regs) { unsigned long addr = instruction_pointer(regs); - siginfo_t info; - clear_siginfo(&info); if (except_info->code != TRAP_BRKPT) pr_err("TRAP: %s PC[0x%lx] signo[%d] code[%d]\n", except_info->kernel_str, regs->pc, @@ -254,12 +252,8 @@ static void do_trap(struct exception_info *except_info, struct pt_regs *regs) die_if_kernel(except_info->kernel_str, regs, addr); - info.si_signo = except_info->signo; - info.si_errno = 0; - info.si_code = except_info->code; - info.si_addr = (void __user *)addr; - - force_sig_info(except_info->signo, &info, current); + force_sig_fault(except_info->signo, except_info->code, + (void __user *)addr, current); } /* -- cgit v1.2.3