diff options
author | Yuntao Wang <ytcoode@gmail.com> | 2023-12-17 11:35:26 +0800 |
---|---|---|
committer | Andrew Morton <akpm@linux-foundation.org> | 2023-12-29 12:22:25 -0800 |
commit | 816d334afa85c836080b41bb6238aea845615ad9 (patch) | |
tree | cb7d14fad85392bf6a2f319498ad9594d04edbe3 | |
parent | 5c28913ed04b29efb75c4ddd6a13469952351858 (diff) |
kexec: modify the meaning of the end parameter in kimage_is_destination_range()
The end parameter received by kimage_is_destination_range() should be the
last valid byte address of the target memory segment plus 1. However, in
the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
the corresponding value passed to kimage_is_destination_range() is the
last valid byte address of the target memory segment, which is 1 less.
There are two ways to fix this bug. We can either correct the logic of
the locate_mem_hole_bottom_up() and locate_mem_hole_top_down() functions,
or we can fix kimage_is_destination_range() by making the end parameter
represent the last valid byte address of the target memory segment. Here,
we choose the second approach.
Due to the modification to kimage_is_destination_range(), we also need to
adjust its callers, such as kimage_alloc_normal_control_pages() and
kimage_alloc_page().
Link: https://lkml.kernel.org/r/20231217033528.303333-2-ytcoode@gmail.com
Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
-rw-r--r-- | kernel/kexec_core.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index 6e0f022987ff..2f039a7d9af9 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -278,8 +278,8 @@ int kimage_is_destination_range(struct kimage *image, unsigned long mstart, mend; mstart = image->segment[i].mem; - mend = mstart + image->segment[i].memsz; - if ((end > mstart) && (start < mend)) + mend = mstart + image->segment[i].memsz - 1; + if ((end >= mstart) && (start <= mend)) return 1; } @@ -372,7 +372,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image, pfn = page_to_boot_pfn(pages); epfn = pfn + count; addr = pfn << PAGE_SHIFT; - eaddr = epfn << PAGE_SHIFT; + eaddr = (epfn << PAGE_SHIFT) - 1; if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) || kimage_is_destination_range(image, addr, eaddr)) { list_add(&pages->lru, &extra_pages); @@ -718,7 +718,7 @@ static struct page *kimage_alloc_page(struct kimage *image, /* If the page is not a destination page use it */ if (!kimage_is_destination_range(image, addr, - addr + PAGE_SIZE)) + addr + PAGE_SIZE - 1)) break; /* |