Messages in this thread Patch in this message | | | Date | Fri, 31 Jul 2015 06:58:29 -0700 | From | tip-bot for Oleg Nesterov <> | Subject | [tip:perf/core] uprobes: Send SIGILL if handle_trampoline() fails |
| |
Commit-ID: 0b5256c7f173258b19d98364adb57f707dda22f3 Gitweb: http://git.kernel.org/tip/0b5256c7f173258b19d98364adb57f707dda22f3 Author: Oleg Nesterov <oleg@redhat.com> AuthorDate: Tue, 21 Jul 2015 15:40:08 +0200 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Fri, 31 Jul 2015 10:38:03 +0200
uprobes: Send SIGILL if handle_trampoline() fails
1. It doesn't make sense to continue if handle_trampoline() fails, change handle_swbp() to always return after this call.
2. Turn pr_warn() into uprobe_warn(), and change handle_trampoline() to send SIGILL on failure. It is pointless to return to user mode with the corrupted instruction_pointer() which we can't restore.
Tested-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Anton Arapov <arapov@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150721134008.GA4745@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- kernel/events/uprobes.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-)
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index d8c702f..eabdc21 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1770,7 +1770,7 @@ handle_uretprobe_chain(struct return_instance *ri, struct pt_regs *regs) up_read(&uprobe->register_rwsem); } -static bool handle_trampoline(struct pt_regs *regs) +static void handle_trampoline(struct pt_regs *regs) { struct uprobe_task *utask; struct return_instance *ri; @@ -1778,11 +1778,11 @@ static bool handle_trampoline(struct pt_regs *regs) utask = current->utask; if (!utask) - return false; + goto sigill; ri = utask->return_instances; if (!ri) - return false; + goto sigill; /* * TODO: we should throw out return_instance's invalidated by @@ -1804,8 +1804,12 @@ static bool handle_trampoline(struct pt_regs *regs) } utask->return_instances = ri; + return; + + sigill: + uprobe_warn(current, "handle uretprobe, sending SIGILL."); + force_sig_info(SIGILL, SEND_SIG_FORCED, current); - return true; } bool __weak arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs) @@ -1824,13 +1828,8 @@ static void handle_swbp(struct pt_regs *regs) int uninitialized_var(is_swbp); bp_vaddr = uprobe_get_swbp_addr(regs); - if (bp_vaddr == get_trampoline_vaddr()) { - if (handle_trampoline(regs)) - return; - - pr_warn("uprobe: unable to handle uretprobe pid/tgid=%d/%d\n", - current->pid, current->tgid); - } + if (bp_vaddr == get_trampoline_vaddr()) + return handle_trampoline(regs); uprobe = find_active_uprobe(bp_vaddr, &is_swbp); if (!uprobe) {
| |