Commit-ID: a70857e46dd13e87ae06bf0e64cb6a2d4f436265 Gitweb: http://git.kernel.org/tip/a70857e46dd13e87ae06bf0e64cb6a2d4f436265 Author: Aaron Tomlin <atom...@redhat.com> AuthorDate: Fri, 12 Sep 2014 14:16:18 +0100 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Fri, 19 Sep 2014 12:35:23 +0200
sched: Add helper for task stack page overrun checking This facility is used in a few places so let's introduce a helper function to improve code readability. Signed-off-by: Aaron Tomlin <atom...@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: aneesh.ku...@linux.vnet.ibm.com Cc: dzic...@redhat.com Cc: b...@redhat.com Cc: jcasti...@redhat.com Cc: o...@redhat.com Cc: r...@redhat.com Cc: pra...@redhat.com Cc: j...@redhat.com Cc: minc...@kernel.org Cc: m...@ellerman.id.au Cc: t...@linutronix.de Cc: han...@cmpxchg.org Cc: Andrew Morton <a...@linux-foundation.org> Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org> Cc: Jiri Olsa <jo...@redhat.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu...@hitachi.com> Cc: Michael Ellerman <m...@ellerman.id.au> Cc: Paul Mackerras <pau...@samba.org> Cc: Seiji Aguchi <seiji.agu...@hds.com> Cc: Steven Rostedt <rost...@goodmis.org> Cc: Yasuaki Ishimatsu <isimatu.yasu...@jp.fujitsu.com> Cc: linuxppc-...@lists.ozlabs.org Link: http://lkml.kernel.org/r/1410527779-8133-3-git-send-email-atom...@redhat.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/powerpc/mm/fault.c | 4 +--- arch/x86/mm/fault.c | 4 +--- include/linux/sched.h | 2 ++ kernel/trace/trace_stack.c | 2 +- 4 files changed, 5 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 35d0760c..99b2f27 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -507,7 +507,6 @@ bail: void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig) { const struct exception_table_entry *entry; - unsigned long *stackend; /* Are we prepared to handle this fault? */ if ((entry = search_exception_tables(regs->nip)) != NULL) { @@ -536,8 +535,7 @@ void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig) printk(KERN_ALERT "Faulting instruction address: 0x%08lx\n", regs->nip); - stackend = end_of_stack(current); - if (*stackend != STACK_END_MAGIC) + if (task_stack_end_corrupted(current)) printk(KERN_ALERT "Thread overran stack, or stack corrupted\n"); die("Kernel access of bad area", regs, sig); diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index bc23a70..6240bc7 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -648,7 +648,6 @@ no_context(struct pt_regs *regs, unsigned long error_code, unsigned long address, int signal, int si_code) { struct task_struct *tsk = current; - unsigned long *stackend; unsigned long flags; int sig; @@ -708,8 +707,7 @@ no_context(struct pt_regs *regs, unsigned long error_code, show_fault_oops(regs, error_code, address); - stackend = end_of_stack(tsk); - if (*stackend != STACK_END_MAGIC) + if (task_stack_end_corrupted(tsk)) printk(KERN_EMERG "Thread overran stack, or stack corrupted\n"); tsk->thread.cr2 = address; diff --git a/include/linux/sched.h b/include/linux/sched.h index 118dca7..18f5262 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2617,6 +2617,8 @@ static inline unsigned long *end_of_stack(struct task_struct *p) } #endif +#define task_stack_end_corrupted(task) \ + (*(end_of_stack(task)) != STACK_END_MAGIC) static inline int object_is_on_stack(void *obj) { diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index 1636e41..16eddb3 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -170,7 +170,7 @@ check_stack(unsigned long ip, unsigned long *stack) i++; } - if (*end_of_stack(current) != STACK_END_MAGIC) { + if (task_stack_end_corrupted(current)) { print_max_stack(); BUG(); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
