updpkg: libre/linux-libre-pae 5.5.2-1

Signed-off-by: David P <megver83@parabola.nu>

1 files changed, 92 insertions, 0 deletions

diff --git a/libre/linux-libre-pae/0004-Btrfs-send-fix-emission-of-invalid-clone-operations-.patch b/libre/linux-libre-pae/0004-Btrfs-send-fix-emission-of-invalid-clone-operations-.patch
new file mode 100644
index 000000000..26c10a8df
--- /dev/null
+++ b/libre/linux-libre-pae/0004-Btrfs-send-fix-emission-of-invalid-clone-operations-.patch
@@ -0,0 +1,92 @@
+From d0910be3493b40233c513c9ad01ac0878ae26a48 Mon Sep 17 00:00:00 2001
+From: Filipe Manana <fdmanana@suse.com>
+Date: Wed, 29 Jan 2020 17:09:53 +0000
+Subject: [PATCH 4/5] Btrfs: send, fix emission of invalid clone operations
+ within the same file
+
+When doing an incremental send and a file has extents shared with itself
+at different file offsets, it's possible for send to emit clone operations
+that will fail at the destination because the source range goes beyond the
+file's current size. This happens when the file size has increased in the
+send snapshot, there is a hole between the shared extents and both shared
+extents are at file offsets which are greater the file's size in the
+parent snapshot.
+
+Example:
+
+  $ mkfs.btrfs -f /dev/sdb
+  $ mount /dev/sdb /mnt/sdb
+
+  $ xfs_io -f -c "pwrite -S 0xf1 0 64K" /mnt/sdb/foobar
+  $ btrfs subvolume snapshot -r /mnt/sdb /mnt/sdb/base
+  $ btrfs send -f /tmp/1.snap /mnt/sdb/base
+
+  # Create a 320K extent at file offset 512K.
+  $ xfs_io -c "pwrite -S 0xab 512K 64K" /mnt/sdb/foobar
+  $ xfs_io -c "pwrite -S 0xcd 576K 64K" /mnt/sdb/foobar
+  $ xfs_io -c "pwrite -S 0xef 640K 64K" /mnt/sdb/foobar
+  $ xfs_io -c "pwrite -S 0x64 704K 64K" /mnt/sdb/foobar
+  $ xfs_io -c "pwrite -S 0x73 768K 64K" /mnt/sdb/foobar
+
+  # Clone part of that 320K extent into a lower file offset (192K).
+  # This file offset is greater than the file's size in the parent
+  # snapshot (64K). Also the clone range is a bit behind the offset of
+  # the 320K extent so that we leave a hole between the shared extents.
+  $ xfs_io -c "reflink /mnt/sdb/foobar 448K 192K 192K" /mnt/sdb/foobar
+
+  $ btrfs subvolume snapshot -r /mnt/sdb /mnt/sdb/incr
+  $ btrfs send -p /mnt/sdb/base -f /tmp/2.snap /mnt/sdb/incr
+
+  $ mkfs.btrfs -f /dev/sdc
+  $ mount /dev/sdc /mnt/sdc
+
+  $ btrfs receive -f /tmp/1.snap /mnt/sdc
+  $ btrfs receive -f /tmp/2.snap /mnt/sdc
+  ERROR: failed to clone extents to foobar: Invalid argument
+
+The problem is that after processing the extent at file offset 256K, which
+refers to the first 128K of the 320K extent created by the buffered write
+operations, we have 'cur_inode_next_write_offset' set to 384K, which
+corresponds to the end offset of the partially shared extent (256K + 128K)
+and to the current file size in the receiver. Then when we process the
+extent at offset 512K, we do extent backreference iteration to figure out
+if we can clone the extent from some other inode or from the same inode,
+and we consider the extent at offset 256K of the same inode as a valid
+source for a clone operation, which is not correct because at that point
+the current file size in the receiver is 384K, which corresponds to the
+end of last processed extent (at file offset 256K), so using a clone
+source range from 256K to 256K + 320K is invalid because that goes past
+the current size of the file (384K) - this makes the receiver get an
+-EINVAL error when attempting the clone operation.
+
+So fix this by excluding clone sources that have a range that goes beyond
+the current file size in the receiver when iterating extent backreferences.
+
+A test case for fstests follows soon.
+
+Fixes: 11f2069c113e02 ("Btrfs: send, allow clone operations within the same file")
+CC: stable@vger.kernel.org # 5.5+
+Reviewed-by: Josef Bacik <josef@toxicpanda.com>
+Signed-off-by: Filipe Manana <fdmanana@suse.com>
+Signed-off-by: David Sterba <dsterba@suse.com>
+---
+ fs/btrfs/send.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
+index 091e5bc8c7ea..a055b657cb85 100644
+--- a/fs/btrfs/send.c
++++ b/fs/btrfs/send.c
+@@ -1269,7 +1269,8 @@ static int __iterate_backrefs(u64 ino, u64 offset, u64 root, void *ctx_)
+ 		 * destination of the stream.
+ 		 */
+ 		if (ino == bctx->cur_objectid &&
+-		    offset >= bctx->sctx->cur_inode_next_write_offset)
++		    offset + bctx->extent_len >
++		    bctx->sctx->cur_inode_next_write_offset)
+ 			return 0;
+ 	}
+ 
+-- 
+2.25.0
+