diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-11-02 09:45:17 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-11-02 09:45:17 -0800 |
| commit | efcd9e0b91bcb92a1dd530d1a1f26eb83a5d21e2 (patch) | |
| tree | 167fb89a3e0ae3b83a89207e0c42a35dcf2a8ad4 /arch/x86/kernel/crash_dump_32.c | |
| parent | 32c5fc10e79a7053ac5728b01a0bff55cbcb9d49 (diff) | |
| parent | 772be899bc022ef2b911c3611b487d417e3269c3 (diff) | |
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Make EFI RTC function depend on 32bit again
x86-64: Fix register leak in 32-bit syscall audting
x86: crash_dump: Fix non-pae kdump kernel memory accesses
x86: Side-step lguest problem by only building cmpxchg8b_emu for pre-Pentium
x86: Remove STACKPROTECTOR_ALL
Diffstat (limited to 'arch/x86/kernel/crash_dump_32.c')
| -rw-r--r-- | arch/x86/kernel/crash_dump_32.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/x86/kernel/crash_dump_32.c b/arch/x86/kernel/crash_dump_32.c index f7cdb3b457a..cd97ce18c29 100644 --- a/arch/x86/kernel/crash_dump_32.c +++ b/arch/x86/kernel/crash_dump_32.c @@ -16,6 +16,22 @@ static void *kdump_buf_page; /* Stores the physical address of elf header of crash image. */ unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX; +static inline bool is_crashed_pfn_valid(unsigned long pfn) +{ +#ifndef CONFIG_X86_PAE + /* + * non-PAE kdump kernel executed from a PAE one will crop high pte + * bits and poke unwanted space counting again from address 0, we + * don't want that. pte must fit into unsigned long. In fact the + * test checks high 12 bits for being zero (pfn will be shifted left + * by PAGE_SHIFT). + */ + return pte_pfn(pfn_pte(pfn, __pgprot(0))) == pfn; +#else + return true; +#endif +} + /** * copy_oldmem_page - copy one page from "oldmem" * @pfn: page frame number to be copied @@ -41,6 +57,9 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, if (!csize) return 0; + if (!is_crashed_pfn_valid(pfn)) + return -EFAULT; + vaddr = kmap_atomic_pfn(pfn, KM_PTE0); if (!userbuf) { |