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-rw-r--r--user/squashfs-tools/0001-mksquashfs-fix-rare-race-in-fragment-waiting-in-file.patch60
1 files changed, 0 insertions, 60 deletions
diff --git a/user/squashfs-tools/0001-mksquashfs-fix-rare-race-in-fragment-waiting-in-file.patch b/user/squashfs-tools/0001-mksquashfs-fix-rare-race-in-fragment-waiting-in-file.patch
deleted file mode 100644
index 51f588818..000000000
--- a/user/squashfs-tools/0001-mksquashfs-fix-rare-race-in-fragment-waiting-in-file.patch
+++ /dev/null
@@ -1,60 +0,0 @@
-From de03266983ceb62e5365aac84fcd3b2fd4d16e6f Mon Sep 17 00:00:00 2001
-From: Phillip Lougher <phillip@squashfs.org.uk>
-Date: Thu, 18 Sep 2014 01:28:11 +0100
-Subject: [PATCH] mksquashfs: fix rare race in fragment waiting in filesystem
- finalisation
-
-Fix a rare race condition in fragment waiting when finalising the
-filesystem. This is a race condition that was initially fixed in 2009,
-but inadvertantly re-introduced in the latest release when the code
-was rewritten.
-
-Background:
-
-When finalising the filesystem, the main control thread needs to ensure
-all the in-flight fragments have been queued to the writer thread before
-asking the writer thread to finish, and then writing the metadata.
-
-It does this by waiting on the fragments_outstanding counter. Once this
-counter reaches 0, it synchronises with the writer thread, waiting until
-the writer thread reports no outstanding data to be written.
-
-However, the main thread can race with the fragment deflator thread(s)
-because the fragment deflator thread(s) decrement the fragments_outstanding
-counter and release the mutex before queueing the compressed fragment
-to the writer thread, i.e. the offending code is:
-
- fragments_outstanding --;
- pthread_mutex_unlock(&fragment_mutex);
- queue_put(to_writer, write_buffer);
-
-In extremely rare circumstances, the main thread may see the
-fragments_outstanding counter is zero before the fragment
-deflator sends the fragment buffer to the writer thread, and synchronise
-with the writer thread, and finalise before the fragment has been written.
-
-The fix is to ensure the fragment is queued to the writer thread
-before releasing the mutex.
-
-Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
----
- squashfs-tools/mksquashfs.c | 2 +-
- 1 file changed, 1 insertion(+), 1 deletion(-)
-
-diff --git a/squashfs-tools/mksquashfs.c b/squashfs-tools/mksquashfs.c
-index 87b7d86..f1fcff1 100644
---- a/squashfs-tools/mksquashfs.c
-+++ b/squashfs-tools/mksquashfs.c
-@@ -2419,8 +2419,8 @@ void *frag_deflator(void *arg)
- write_buffer->block = bytes;
- bytes += compressed_size;
- fragments_outstanding --;
-- pthread_mutex_unlock(&fragment_mutex);
- queue_put(to_writer, write_buffer);
-+ pthread_mutex_unlock(&fragment_mutex);
- TRACE("Writing fragment %lld, uncompressed size %d, "
- "compressed size %d\n", file_buffer->block,
- file_buffer->size, compressed_size);
---
-2.10.2
-