mirror of https://github.com/torvalds/linux.git
508a92741a
This patch fixes a crash caused by an interrupt coming in when an IRQ stack is being torn down. When this happens, handle_signal will loop, setting up the IRQ stack again because the tearing down had finished, and handling whatever signals had come in. However, to_irq_stack returns a mask of pending signals to be handled, plus bit zero is set if the IRQ stack was already active, and thus shouldn't be torn down. This causes a problem because when handle_signal goes around the loop, sig will be zero, and to_irq_stack will duly set bit zero in the returned mask, faking handle_signal into believing that it shouldn't tear down the IRQ stack and return thread_info pointers back to their original values. This will eventually cause a crash, as the IRQ stack thread_info will continue pointing to the original task_struct and an interrupt will look into it after it has been freed. The fix is to stop passing a signal number into to_irq_stack. Rather, the pending signals mask is initialized beforehand with the bit for sig already set. References to sig in to_irq_stack can be replaced with references to the mask. [akpm@linux-foundation.org: use UL] Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| skas | ||
| sysdep-i386 | ||
| sysdep-ia64 | ||
| sysdep-ppc | ||
| sysdep-x86_64 | ||
| tt | ||
| aio.h | ||
| arch.h | ||
| as-layout.h | ||
| chan_kern.h | ||
| chan_user.h | ||
| choose-mode.h | ||
| common-offsets.h | ||
| elf_user.h | ||
| frame_kern.h | ||
| init.h | ||
| initrd.h | ||
| irq_kern.h | ||
| irq_user.h | ||
| kern.h | ||
| kern_util.h | ||
| line.h | ||
| longjmp.h | ||
| mconsole.h | ||
| mconsole_kern.h | ||
| mem.h | ||
| mem_kern.h | ||
| mem_user.h | ||
| misc_constants.h | ||
| mode.h | ||
| mode_kern.h | ||
| net_kern.h | ||
| net_user.h | ||
| os.h | ||
| process.h | ||
| ptrace_user.h | ||
| registers.h | ||
| sigcontext.h | ||
| sigio.h | ||
| signal_kern.h | ||
| skas_ptrace.h | ||
| skas_ptregs.h | ||
| syscall.h | ||
| sysrq.h | ||
| task.h | ||
| tempfile.h | ||
| tlb.h | ||
| ubd_user.h | ||
| um_malloc.h | ||
| um_mmu.h | ||
| um_uaccess.h | ||
| uml_uaccess.h | ||
| user.h | ||