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author | Josh Boyer <jwboyer@redhat.com> | 2012-03-20 10:31:52 -0400 |
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committer | Josh Boyer <jwboyer@redhat.com> | 2012-03-20 10:35:32 -0400 |
commit | 364473e5c59b1d2a2a8c2dd053f9a0013d37110e (patch) | |
tree | 0715e6d3e869574fa3bd65d13231166e93f4a50c /shlib_base_randomize.patch | |
parent | b7da64597e570ad8c8a5625e3486c73bf85a7e90 (diff) | |
download | kernel-364473e5c59b1d2a2a8c2dd053f9a0013d37110e.tar.gz kernel-364473e5c59b1d2a2a8c2dd053f9a0013d37110e.tar.xz kernel-364473e5c59b1d2a2a8c2dd053f9a0013d37110e.zip |
CVE-2012-1568: execshield: predictable ascii armour base address (rhbz 804957)
Diffstat (limited to 'shlib_base_randomize.patch')
-rw-r--r-- | shlib_base_randomize.patch | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/shlib_base_randomize.patch b/shlib_base_randomize.patch new file mode 100644 index 000000000..80e4d644b --- /dev/null +++ b/shlib_base_randomize.patch @@ -0,0 +1,69 @@ +diff -uNrp kernel-3.2.fc16.orig/arch/x86/mm/mmap.c kernel-3.2.fc16.new/arch/x86/mm/mmap.c +--- kernel-3.2.fc16.orig/arch/x86/mm/mmap.c 2012-03-19 16:47:03.495169091 -0400 ++++ kernel-3.2.fc16.new/arch/x86/mm/mmap.c 2012-03-19 16:50:03.574168052 -0400 +@@ -106,6 +106,10 @@ static unsigned long mmap_legacy_base(vo + return TASK_UNMAPPED_BASE + mmap_rnd(); + } + ++#ifdef CONFIG_X86_32 ++ #define SHLIB_BASE 0x00111000 ++#endif ++ + /* + * This function, called very early during the creation of a new + * process VM image, sets up which VM layout function to use: +@@ -126,8 +126,10 @@ void arch_pick_mmap_layout(struct mm_str + #ifdef CONFIG_X86_32 + if (!(current->personality & READ_IMPLIES_EXEC) + && !(__supported_pte_mask & _PAGE_NX) +- && mmap_is_ia32()) ++ && mmap_is_ia32()) { ++ mm->shlib_base = SHLIB_BASE + mmap_rnd(); + mm->get_unmapped_exec_area = arch_get_unmapped_exec_area; ++ } + #endif + mm->unmap_area = arch_unmap_area_topdown; + } +diff -uNrp kernel-3.2.fc16.orig/include/linux/mm_types.h kernel-3.2.fc16.new/include/linux/mm_types.h +--- kernel-3.2.fc16.orig/include/linux/mm_types.h 2012-03-19 16:46:47.382169153 -0400 ++++ kernel-3.2.fc16.new/include/linux/mm_types.h 2012-03-19 16:50:40.738168219 -0400 +@@ -300,6 +300,7 @@ struct mm_struct { + void (*unmap_area) (struct mm_struct *mm, unsigned long addr); + #endif + unsigned long mmap_base; /* base of mmap area */ ++ unsigned long shlib_base; /* base of lib map area (ASCII armour)*/ + unsigned long task_size; /* size of task vm space */ + unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */ + unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */ +diff -uNrp kernel-3.2.fc16.orig/mm/mmap.c kernel-3.2.fc16.new/mm/mmap.c +--- kernel-3.2.fc16.orig/mm/mmap.c 2012-03-19 16:46:15.791169274 -0400 ++++ kernel-3.2.fc16.new/mm/mmap.c 2012-03-19 16:51:37.351166875 -0400 +@@ -1594,8 +1594,6 @@ static bool should_randomize(void) + !(current->personality & ADDR_NO_RANDOMIZE); + } + +-#define SHLIB_BASE 0x00110000 +- + unsigned long + arch_get_unmapped_exec_area(struct file *filp, unsigned long addr0, + unsigned long len0, unsigned long pgoff, unsigned long flags) +@@ -1612,8 +1610,8 @@ arch_get_unmapped_exec_area(struct file + return addr; + + if (!addr) +- addr = !should_randomize() ? SHLIB_BASE : +- randomize_range(SHLIB_BASE, 0x01000000, len); ++ addr = !should_randomize() ? mm->shlib_base : ++ randomize_range(mm->shlib_base, 0x01000000, len); + + if (addr) { + addr = PAGE_ALIGN(addr); +@@ -1623,7 +1621,7 @@ arch_get_unmapped_exec_area(struct file + return addr; + } + +- addr = SHLIB_BASE; ++ addr = mm->shlib_base; + for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { + /* At this point: (!vma || addr < vma->vm_end). */ + if (TASK_SIZE - len < addr) |