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| author | Adrian Hunter <adrian.hunter@intel.com> | 2023-09-11 14:21:14 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-10-04 10:32:22 -0700 |
| commit | e538a582097878c536c68002c79722e4a037c080 (patch) | |
| tree | 00f5c86426f41bf79ce70f4e461b984824b9c1e6 /fs/proc | |
| parent | 7cd34dd3c9bf1d67ce7d1ab3fe8886c583ae0d9a (diff) | |
| download | linux-e538a582097878c536c68002c79722e4a037c080.tar.gz linux-e538a582097878c536c68002c79722e4a037c080.tar.bz2 linux-e538a582097878c536c68002c79722e4a037c080.zip | |
proc/kcore: do not try to access unaccepted memory
Support for unaccepted memory was added recently, refer commit
dcdfdd40fa82 ("mm: Add support for unaccepted memory"), whereby a virtual
machine may need to accept memory before it can be used.
Do not try to access unaccepted memory because it can cause the guest to
fail.
For /proc/kcore, which is read-only and does not support mmap, this means a
read of unaccepted memory will return zeros.
Link: https://lkml.kernel.org/r/20230911112114.91323-3-adrian.hunter@intel.com
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs/proc')
| -rw-r--r-- | fs/proc/kcore.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index 23fc24d16b31..6422e569b080 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -546,7 +546,8 @@ static ssize_t read_kcore_iter(struct kiocb *iocb, struct iov_iter *iter) * and explicitly excluded physical ranges. */ if (!page || PageOffline(page) || - is_page_hwpoison(page) || !pfn_is_ram(pfn)) { + is_page_hwpoison(page) || !pfn_is_ram(pfn) || + pfn_is_unaccepted_memory(pfn)) { if (iov_iter_zero(tsz, iter) != tsz) { ret = -EFAULT; goto out; |