1. register_for_each_vma() checks that vma_address() == vaddr but this is not enough. We should also ensure that vaddr >= vm_start, find_vma() guarantees "vaddr < vm_end" only.
2. After the prevous changes, register_for_each_vma() is the only reason why vma_address() has to return loff_t, all other users know that we have the valid mapping at this offset and thus the overflow is not possible. Change the code to use vaddr_to_offset() instead, imho this looks more clean/understandable and now we can change vma_address(). 3. While at it, remove the unnecessary type-cast. Signed-off-by: Oleg Nesterov <[email protected]> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> --- kernel/events/uprobes.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 5c87042..734e199 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -823,12 +823,13 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register) goto free; down_write(&mm->mmap_sem); - vma = find_vma(mm, (unsigned long)info->vaddr); - if (!vma || !valid_vma(vma, is_register)) + vma = find_vma(mm, info->vaddr); + if (!vma || !valid_vma(vma, is_register) || + vma->vm_file->f_mapping->host != uprobe->inode) goto unlock; - if (vma->vm_file->f_mapping->host != uprobe->inode || - vma_address(vma, uprobe->offset) != info->vaddr) + if (vma->vm_start > info->vaddr || + vaddr_to_offset(vma, info->vaddr) != uprobe->offset) goto unlock; if (is_register) { -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
