[RFC v16][PATCH 01/43] c/r: extend arch_setup_additional_pages()
From: Oren Laadan <hidden>
Date: 2009-05-27 18:26:44
Also in:
linux-mm, lkml
Subsystem:
exec & binfmt api, elf, filesystems (vfs and infrastructure), linux for powerpc (32-bit and 64-bit), s390 architecture, superh, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Kees Cook, Alexander Viro, Christian Brauner, Madhavan Srinivasan, Michael Ellerman, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Yoshinori Sato, Rich Felker, John Paul Adrian Glaubitz, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Alexey Dobriyan <redacted> Add "start" argument, to request to map vDSO to a specific place, and fail the operation if not. This is useful for restart(2) to ensure that memory layout is restore exactly as needed. Signed-off-by: Alexey Dobriyan <redacted> Signed-off-by: Oren Laadan <redacted> --- arch/powerpc/include/asm/elf.h | 1 + arch/powerpc/kernel/vdso.c | 11 ++++++++++- arch/s390/include/asm/elf.h | 2 +- arch/s390/kernel/vdso.c | 13 ++++++++++++- arch/sh/include/asm/elf.h | 1 + arch/sh/kernel/vsyscall/vsyscall.c | 2 +- arch/x86/include/asm/elf.h | 3 ++- arch/x86/vdso/vdso32-setup.c | 9 +++++++-- arch/x86/vdso/vma.c | 9 +++++++-- fs/binfmt_elf.c | 2 +- 10 files changed, 43 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/include/asm/elf.h b/arch/powerpc/include/asm/elf.h
index d6b4a12..3946e01 100644
--- a/arch/powerpc/include/asm/elf.h
+++ b/arch/powerpc/include/asm/elf.h@@ -271,6 +271,7 @@ extern int ucache_bsize; #define ARCH_HAS_SETUP_ADDITIONAL_PAGES struct linux_binprm; extern int arch_setup_additional_pages(struct linux_binprm *bprm, + unsigned long start, int uses_interp); #define VDSO_AUX_ENT(a,b) NEW_AUX_ENT(a,b);
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index ad06d5c..48beff6 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c@@ -184,7 +184,8 @@ static void dump_vdso_pages(struct vm_area_struct * vma) * This is called from binfmt_elf, we create the special vma for the * vDSO and insert it into the mm struct tree */ -int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +int arch_setup_additional_pages(struct linux_binprm *bprm, + unsigned long start, int uses_interp) { struct mm_struct *mm = current->mm; struct page **vdso_pagelist;
@@ -211,6 +212,10 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) vdso_base = VDSO32_MBASE; #endif + /* in case restart(2) mandates a specific location */ + if (start) + vdso_base = start; + current->mm->context.vdso_base = 0; /* vDSO has a problem and was disabled, just don't "enable" it for the
@@ -234,6 +239,10 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) goto fail_mmapsem; } + /* for restart(2), double check that we got we asked for */ + if (start && vdso_base != start) + goto fail_mmapsem; + /* * our vma flags don't have VM_WRITE so by default, the process isn't * allowed to write those pages.
diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h
index 74d0bbb..54235bc 100644
--- a/arch/s390/include/asm/elf.h
+++ b/arch/s390/include/asm/elf.h@@ -205,6 +205,6 @@ do { \ struct linux_binprm; #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 -int arch_setup_additional_pages(struct linux_binprm *, int); +int arch_setup_additional_pages(struct linux_binprm *, unsigned long, int); #endif
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
index 89b2e7f..bab43b3 100644
--- a/arch/s390/kernel/vdso.c
+++ b/arch/s390/kernel/vdso.c@@ -182,7 +182,8 @@ static void vdso_init_cr5(void) * This is called from binfmt_elf, we create the special vma for the * vDSO and insert it into the mm struct tree */ -int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +int arch_setup_additional_pages(struct linux_binprm *bprm, + unsigned long start, int uses_interp) { struct mm_struct *mm = current->mm; struct page **vdso_pagelist;
@@ -213,6 +214,10 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) vdso_pages = vdso32_pages; #endif + /* in case restart(2) mandates a specific location */ + if (start) + vdso_base = start; + /* * vDSO has a problem and was disabled, just don't "enable" it for * the process
@@ -235,6 +240,12 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) goto out_up; } + /* for restart(2), double check that we got we asked for */ + if (start && vdso_base != start) { + rc = -EINVAL; + goto out_up; + } + /* * our vma flags don't have VM_WRITE so by default, the process * isn't allowed to write those pages.
diff --git a/arch/sh/include/asm/elf.h b/arch/sh/include/asm/elf.h
index ccb1d93..6c27b1f 100644
--- a/arch/sh/include/asm/elf.h
+++ b/arch/sh/include/asm/elf.h@@ -202,6 +202,7 @@ do { \ #define ARCH_HAS_SETUP_ADDITIONAL_PAGES struct linux_binprm; extern int arch_setup_additional_pages(struct linux_binprm *bprm, + unsigned long start, int uses_interp); extern unsigned int vdso_enabled;
diff --git a/arch/sh/kernel/vsyscall/vsyscall.c b/arch/sh/kernel/vsyscall/vsyscall.c
index 3f7e415..64c70e5 100644
--- a/arch/sh/kernel/vsyscall/vsyscall.c
+++ b/arch/sh/kernel/vsyscall/vsyscall.c@@ -59,7 +59,7 @@ int __init vsyscall_init(void) } /* Setup a VMA at program startup for the vsyscall page */ -int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +int arch_setup_additional_pages(struct linux_binprm *bprm, unsigned long start, int uses_interp) { struct mm_struct *mm = current->mm; unsigned long addr;
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index 83c1bc8..a4398c8 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h@@ -336,9 +336,10 @@ struct linux_binprm; #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 extern int arch_setup_additional_pages(struct linux_binprm *bprm, + unsigned long start, int uses_interp); -extern int syscall32_setup_pages(struct linux_binprm *, int exstack); +extern int syscall32_setup_pages(struct linux_binprm *, unsigned long start, int exstack); #define compat_arch_setup_additional_pages syscall32_setup_pages extern unsigned long arch_randomize_brk(struct mm_struct *mm);
diff --git a/arch/x86/vdso/vdso32-setup.c b/arch/x86/vdso/vdso32-setup.c
index 1241f11..9c72a23 100644
--- a/arch/x86/vdso/vdso32-setup.c
+++ b/arch/x86/vdso/vdso32-setup.c@@ -310,7 +310,8 @@ int __init sysenter_setup(void) } /* Setup a VMA at program startup for the vsyscall page */ -int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +int arch_setup_additional_pages(struct linux_binprm *bprm, + unsigned long start, int uses_interp) { struct mm_struct *mm = current->mm; unsigned long addr;
@@ -331,13 +332,17 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) if (compat) addr = VDSO_HIGH_BASE; else { - addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0); + addr = get_unmapped_area(NULL, start, PAGE_SIZE, 0, 0); if (IS_ERR_VALUE(addr)) { ret = addr; goto up_fail; } } + /* for restart(2), double check that we got we asked for */ + if (start && addr != start) + goto up_fail; + if (compat_uses_vma || !compat) { /* * MAYWRITE to allow gdb to COW and set breakpoints
diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c
index 7133cdf..81fce6d 100644
--- a/arch/x86/vdso/vma.c
+++ b/arch/x86/vdso/vma.c@@ -98,7 +98,8 @@ static unsigned long vdso_addr(unsigned long start, unsigned len) /* Setup a VMA at program startup for the vsyscall page. Not called for compat tasks */ -int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +int arch_setup_additional_pages(struct linux_binprm *bprm, + unsigned long start, int uses_interp) { struct mm_struct *mm = current->mm; unsigned long addr;
@@ -108,13 +109,17 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) return 0; down_write(&mm->mmap_sem); - addr = vdso_addr(mm->start_stack, vdso_size); + addr = start ? : vdso_addr(mm->start_stack, vdso_size); addr = get_unmapped_area(NULL, addr, vdso_size, 0, 0); if (IS_ERR_VALUE(addr)) { ret = addr; goto up_fail; } + /* for restart(2), double check that we got we asked for */ + if (start && addr != start) + goto up_fail; + ret = install_special_mapping(mm, addr, vdso_size, VM_READ|VM_EXEC| VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 40381df..aa9a802 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c@@ -945,7 +945,7 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) set_binfmt(&elf_format); #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES - retval = arch_setup_additional_pages(bprm, !!elf_interpreter); + retval = arch_setup_additional_pages(bprm, 0, !!elf_interpreter); if (retval < 0) { send_sig(SIGKILL, current, 0); goto out;
--
1.6.0.4
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