Commit-ID: fa33215422fd415a07ec2a00e9f1acdaf0fa8e94 Gitweb: https://git.kernel.org/tip/fa33215422fd415a07ec2a00e9f1acdaf0fa8e94 Author: Andy Lutomirski <[email protected]> AuthorDate: Sun, 14 Apr 2019 17:59:39 +0200 Committer: Borislav Petkov <[email protected]> CommitDate: Wed, 17 Apr 2019 12:26:50 +0200
x86/dumpstack: Fix off-by-one errors in stack identification The get_stack_info() function is off-by-one when checking whether an address is on a IRQ stack or a IST stack. This prevents an overflowed IRQ or IST stack from being dumped properly. [ tglx: Do the same for 32-bit ] Signed-off-by: Andy Lutomirski <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Sean Christopherson <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: x86-ml <[email protected]> Link: https://lkml.kernel.org/r/[email protected] --- arch/x86/kernel/dumpstack_32.c | 4 ++-- arch/x86/kernel/dumpstack_64.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index cd53f3030e40..d305440ebe9c 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -41,7 +41,7 @@ static bool in_hardirq_stack(unsigned long *stack, struct stack_info *info) * This is a software stack, so 'end' can be a valid stack pointer. * It just means the stack is empty. */ - if (stack <= begin || stack > end) + if (stack < begin || stack > end) return false; info->type = STACK_TYPE_IRQ; @@ -66,7 +66,7 @@ static bool in_softirq_stack(unsigned long *stack, struct stack_info *info) * This is a software stack, so 'end' can be a valid stack pointer. * It just means the stack is empty. */ - if (stack <= begin || stack > end) + if (stack < begin || stack > end) return false; info->type = STACK_TYPE_SOFTIRQ; diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index 5cdb9e84da57..90f0fa88cbb3 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -65,7 +65,7 @@ static bool in_exception_stack(unsigned long *stack, struct stack_info *info) begin = end - (exception_stack_sizes[k] / sizeof(long)); regs = (struct pt_regs *)end - 1; - if (stack <= begin || stack >= end) + if (stack < begin || stack >= end) continue; info->type = STACK_TYPE_EXCEPTION + k; @@ -88,7 +88,7 @@ static bool in_irq_stack(unsigned long *stack, struct stack_info *info) * This is a software stack, so 'end' can be a valid stack pointer. * It just means the stack is empty. */ - if (stack <= begin || stack > end) + if (stack < begin || stack >= end) return false; info->type = STACK_TYPE_IRQ;
