[PATCH 13/47] xfs: check _alloc_read_agf buffer pointer before using
From: Christoph Hellwig <hch@lst.de>
Date: 2017-09-17 21:07:19
Also in:
stable
Subsystem:
filesystems (vfs and infrastructure), the rest, xfs filesystem · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds, Carlos Maiolino
From: "Darrick J. Wong" <redacted> commit 10479e2dea83d4c421ad05dfc55d918aa8dfc0cd upstream. In some circumstances, _alloc_read_agf can return an error code of zero but also a null AGF buffer pointer. Check for this and jump out. Fixes-coverity-id: 1415250 Fixes-coverity-id: 1415320 Signed-off-by: Darrick J. Wong <redacted> Reviewed-by: Brian Foster <redacted> --- fs/xfs/libxfs/xfs_refcount.c | 4 ++++ fs/xfs/xfs_reflink.c | 2 ++ 2 files changed, 6 insertions(+)
diff --git a/fs/xfs/libxfs/xfs_refcount.c b/fs/xfs/libxfs/xfs_refcount.c
index e17016163542..d71cb63cdea3 100644
--- a/fs/xfs/libxfs/xfs_refcount.c
+++ b/fs/xfs/libxfs/xfs_refcount.c@@ -1640,6 +1640,10 @@ xfs_refcount_recover_cow_leftovers( error = xfs_alloc_read_agf(mp, tp, agno, 0, &agbp); if (error) goto out_trans; + if (!agbp) { + error = -ENOMEM; + goto out_trans; + } cur = xfs_refcountbt_init_cursor(mp, tp, agbp, agno, NULL); /* Find all the leftover CoW staging extents. */
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 350fc64441b1..0015c19c7455 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c@@ -169,6 +169,8 @@ xfs_reflink_find_shared( error = xfs_alloc_read_agf(mp, NULL, agno, 0, &agbp); if (error) return error; + if (!agbp) + return -ENOMEM; cur = xfs_refcountbt_init_cursor(mp, NULL, agbp, agno, NULL);
--
2.14.1