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authorHugh Dickins <hughd@google.com>2023-07-23 14:05:54 -0700
committerAndrew Morton <akpm@linux-foundation.org>2023-07-27 13:07:03 -0700
commitfa598952fac059054316dccb2213478ccb81a0d1 (patch)
treee1af0830fa7eb13a73c2688784a399704a9380a1 /mm/shmem.c
parent253e5df8b8f0145adb090f57c6f4e6efa52d738e (diff)
downloadlinux-fa598952fac059054316dccb2213478ccb81a0d1.tar.gz
shmem: minor fixes to splice-read implementation
HWPoison: my reading of folio_test_hwpoison() is that it only tests the head page of a large folio, whereas splice_folio_into_pipe() will splice as much of the folio as it can: so for safety we should also check the has_hwpoisoned flag, set if any of the folio's pages are hwpoisoned. (Perhaps that ugliness can be improved at the mm end later.) The call to splice_zeropage_into_pipe() risked overrunning past EOF: ask it for "part" not "len". Link: https://lkml.kernel.org/r/32c72c9c-72a8-115f-407d-f0148f368@google.com Fixes: bd194b187115 ("shmem: Implement splice-read") Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: David Howells <dhowells@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/shmem.c')
-rw-r--r--mm/shmem.c9
1 files changed, 6 insertions, 3 deletions
diff --git a/mm/shmem.c b/mm/shmem.c
index 2f2e0e6180726c..f5af4b943e4286 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2796,7 +2796,8 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos,
if (*ppos >= i_size_read(inode))
break;
- error = shmem_get_folio(inode, *ppos / PAGE_SIZE, &folio, SGP_READ);
+ error = shmem_get_folio(inode, *ppos / PAGE_SIZE, &folio,
+ SGP_READ);
if (error) {
if (error == -EINVAL)
error = 0;
@@ -2805,7 +2806,9 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos,
if (folio) {
folio_unlock(folio);
- if (folio_test_hwpoison(folio)) {
+ if (folio_test_hwpoison(folio) ||
+ (folio_test_large(folio) &&
+ folio_test_has_hwpoisoned(folio))) {
error = -EIO;
break;
}
@@ -2841,7 +2844,7 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos,
folio_put(folio);
folio = NULL;
} else {
- n = splice_zeropage_into_pipe(pipe, *ppos, len);
+ n = splice_zeropage_into_pipe(pipe, *ppos, part);
}
if (!n)