diff options
| author | Masoud Asgharifard Sharbiani <masouds@google.com> | 2007-07-22 11:12:28 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-22 11:03:37 -0700 |
| commit | abd4f7505bafdd6c5319fe3cb5caf9af6104e17a (patch) | |
| tree | a543fce720331dbf6194a2c0471f36b7727b9736 /arch/x86_64/kernel | |
| parent | 5fa63fccc579ac609fc7f86d29ccb3a2edf910d7 (diff) | |
x86: i386-show-unhandled-signals-v3
This patch makes the i386 behave the same way that x86_64 does when a
segfault happens. A line gets printed to the kernel log so that tools
that need to check for failures can behave more uniformly between
debug.show_unhandled_signals sysctl variable to 0 (or by doing echo 0 >
/proc/sys/debug/exception-trace)
Also, all of the lines being printed are now using printk_ratelimit() to
deny the ability of DoS from a local user with a program like the
following:
main()
{
while (1)
if (!fork()) *(int *)0 = 0;
}
This new revision also includes the fix that Andrew did which got rid of
new sysctl that was added to the system in earlier versions of this.
Also, 'show-unhandled-signals' sysctl has been renamed back to the old
'exception-trace' to avoid breakage of people's scripts.
AK: Enabling by default for i386 will be likely controversal, but let's see what happens
AK: Really folks, before complaining just fix your segfaults
AK: I bet this will find a lot of silent issues
Signed-off-by: Masoud Sharbiani <masouds@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
[ Personally, I've found the complaints useful on x86-64, so I'm all for
this. That said, I wonder if we could do it more prettily.. -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86_64/kernel')
| -rw-r--r-- | arch/x86_64/kernel/signal.c | 2 | ||||
| -rw-r--r-- | arch/x86_64/kernel/traps.c | 6 |
2 files changed, 5 insertions, 3 deletions
diff --git a/arch/x86_64/kernel/signal.c b/arch/x86_64/kernel/signal.c index 4886afcd6287..739175b01e06 100644 --- a/arch/x86_64/kernel/signal.c +++ b/arch/x86_64/kernel/signal.c @@ -487,7 +487,7 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) void signal_fault(struct pt_regs *regs, void __user *frame, char *where) { struct task_struct *me = current; - if (exception_trace) + if (show_unhandled_signals && printk_ratelimit()) printk("%s[%d] bad frame in %s frame:%p rip:%lx rsp:%lx orax:%lx\n", me->comm,me->pid,where,frame,regs->rip,regs->rsp,regs->orig_rax); diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c index 8713ad4a4db1..03888420775d 100644 --- a/arch/x86_64/kernel/traps.c +++ b/arch/x86_64/kernel/traps.c @@ -584,7 +584,8 @@ static void __kprobes do_trap(int trapnr, int signr, char *str, tsk->thread.error_code = error_code; tsk->thread.trap_no = trapnr; - if (exception_trace && unhandled_signal(tsk, signr)) + if (show_unhandled_signals && unhandled_signal(tsk, signr) && + printk_ratelimit()) printk(KERN_INFO "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n", tsk->comm, tsk->pid, str, @@ -688,7 +689,8 @@ asmlinkage void __kprobes do_general_protection(struct pt_regs * regs, tsk->thread.error_code = error_code; tsk->thread.trap_no = 13; - if (exception_trace && unhandled_signal(tsk, SIGSEGV)) + if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) && + printk_ratelimit()) printk(KERN_INFO "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n", tsk->comm, tsk->pid, |