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@@ -1,89 +0,0 @@
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-From: Richard Weinberger <[email protected]>
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-Date: Wed, 7 Nov 2018 23:04:43 +0100
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-Subject: [PATCH] ubifs: Handle re-linking of inodes correctly while recovery
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-MIME-Version: 1.0
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-Content-Type: text/plain; charset=UTF-8
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-Content-Transfer-Encoding: 8bit
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-
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-UBIFS's recovery code strictly assumes that a deleted inode will never
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-come back, therefore it removes all data which belongs to that inode
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-as soon it faces an inode with link count 0 in the replay list.
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-Before O_TMPFILE this assumption was perfectly fine. With O_TMPFILE
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-it can lead to data loss upon a power-cut.
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-
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-Consider a journal with entries like:
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-0: inode X (nlink = 0) /* O_TMPFILE was created */
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-1: data for inode X /* Someone writes to the temp file */
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-2: inode X (nlink = 0) /* inode was changed, xattr, chmod, … */
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-3: inode X (nlink = 1) /* inode was re-linked via linkat() */
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-
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-Upon replay of entry #2 UBIFS will drop all data that belongs to inode X,
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-this will lead to an empty file after mounting.
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-
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-As solution for this problem, scan the replay list for a re-link entry
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-before dropping data.
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-
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-Fixes: 474b93704f32 ("ubifs: Implement O_TMPFILE")
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-Cc: [email protected]
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-Cc: Russell Senior <[email protected]>
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-Cc: Rafał Miłecki <[email protected]>
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-Reported-by: Russell Senior <[email protected]>
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-Reported-by: Rafał Miłecki <[email protected]>
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-Signed-off-by: Richard Weinberger <[email protected]>
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----
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- fs/ubifs/replay.c | 37 +++++++++++++++++++++++++++++++++++++
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- 1 file changed, 37 insertions(+)
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-
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---- a/fs/ubifs/replay.c
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-+++ b/fs/ubifs/replay.c
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-@@ -210,6 +210,38 @@ static int trun_remove_range(struct ubif
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- }
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-
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- /**
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-+ * inode_still_linked - check whether inode in question will be re-linked.
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-+ * @c: UBIFS file-system description object
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-+ * @rino: replay entry to test
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-+ *
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-+ * O_TMPFILE files can be re-linked, this means link count goes from 0 to 1.
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-+ * This case needs special care, otherwise all references to the inode will
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-+ * be removed upon the first replay entry of an inode with link count 0
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-+ * is found.
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-+ */
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-+static bool inode_still_linked(struct ubifs_info *c, struct replay_entry *rino)
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-+{
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-+ struct replay_entry *r;
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-+
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-+ ubifs_assert(rino->deletion);
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-+ ubifs_assert(key_type(c, &rino->key) == UBIFS_INO_KEY);
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-+
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-+ /*
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-+ * Find the most recent entry for the inode behind @rino and check
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-+ * whether it is a deletion.
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-+ */
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-+ list_for_each_entry_reverse(r, &c->replay_list, list) {
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-+ ubifs_assert(r->sqnum >= rino->sqnum);
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-+ if (key_inum(c, &r->key) == key_inum(c, &rino->key))
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-+ return r->deletion == 0;
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-+
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-+ }
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-+
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-+ ubifs_assert(0);
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-+ return false;
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-+}
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-+
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-+/**
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- * apply_replay_entry - apply a replay entry to the TNC.
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- * @c: UBIFS file-system description object
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- * @r: replay entry to apply
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-@@ -239,6 +271,11 @@ static int apply_replay_entry(struct ubi
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- {
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- ino_t inum = key_inum(c, &r->key);
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-
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-+ if (inode_still_linked(c, r)) {
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-+ err = 0;
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-+ break;
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-+ }
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-+
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- err = ubifs_tnc_remove_ino(c, inum);
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- break;
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- }
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