diff options
| -rw-r--r-- | fs/binfmt_elf.c | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 295cbaa0e58..ba24cb2ff6c 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -1262,7 +1262,7 @@ static int dump_seek(struct file *file, loff_t off) * * I think we should skip something. But I am not sure how. H.J. */ -static int maydump(struct vm_area_struct *vma) +static int maydump(struct vm_area_struct *vma, unsigned long mm_flags) { /* The vma can be set up to tell us the answer directly. */ if (vma->vm_flags & VM_ALWAYSDUMP) @@ -1272,15 +1272,19 @@ static int maydump(struct vm_area_struct *vma) if (vma->vm_flags & (VM_IO | VM_RESERVED)) return 0; - /* Dump shared memory only if mapped from an anonymous file. */ - if (vma->vm_flags & VM_SHARED) - return vma->vm_file->f_path.dentry->d_inode->i_nlink == 0; + /* By default, dump shared memory if mapped from an anonymous file. */ + if (vma->vm_flags & VM_SHARED) { + if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0) + return test_bit(MMF_DUMP_ANON_SHARED, &mm_flags); + else + return test_bit(MMF_DUMP_MAPPED_SHARED, &mm_flags); + } - /* If it hasn't been written to, don't write it out */ + /* By default, if it hasn't been written to, don't write it out. */ if (!vma->anon_vma) - return 0; + return test_bit(MMF_DUMP_MAPPED_PRIVATE, &mm_flags); - return 1; + return test_bit(MMF_DUMP_ANON_PRIVATE, &mm_flags); } /* An ELF note in memory */ @@ -1572,6 +1576,7 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file) #endif int thread_status_size = 0; elf_addr_t *auxv; + unsigned long mm_flags; #ifdef ELF_CORE_WRITE_EXTRA_NOTES int extra_notes_size; #endif @@ -1715,6 +1720,13 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file) dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); + /* + * We must use the same mm->flags while dumping core to avoid + * inconsistency between the program headers and bodies, otherwise an + * unusable core file can be generated. + */ + mm_flags = current->mm->flags; + /* Write program headers for segments dump */ for (vma = first_vma(current, gate_vma); vma != NULL; vma = next_vma(vma, gate_vma)) { @@ -1727,7 +1739,7 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file) phdr.p_offset = offset; phdr.p_vaddr = vma->vm_start; phdr.p_paddr = 0; - phdr.p_filesz = maydump(vma) ? sz : 0; + phdr.p_filesz = maydump(vma, mm_flags) ? sz : 0; phdr.p_memsz = sz; offset += phdr.p_filesz; phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0; @@ -1771,7 +1783,7 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file) vma = next_vma(vma, gate_vma)) { unsigned long addr; - if (!maydump(vma)) + if (!maydump(vma, mm_flags)) continue; for (addr = vma->vm_start; |