Patch "f2fs: sanity check segment count" has been added to the 3.18-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    f2fs: sanity check segment count

to the 3.18-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     f2fs-sanity-check-segment-count.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From b9dd46188edc2f0d1f37328637860bb65a771124 Mon Sep 17 00:00:00 2001
From: Jin Qian <jinqian@google.com>
Date: Tue, 25 Apr 2017 16:28:48 -0700
Subject: f2fs: sanity check segment count

From: Jin Qian <jinqian@google.com>

commit b9dd46188edc2f0d1f37328637860bb65a771124 upstream.

F2FS uses 4 bytes to represent block address. As a result, supported
size of disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.

Signed-off-by: Jin Qian <jinqian@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/f2fs/super.c         |    7 +++++++
 include/linux/f2fs_fs.h |    6 ++++++
 2 files changed, 13 insertions(+)

--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -913,6 +913,13 @@ static int sanity_check_raw_super(struct
 		return 1;
 	}
 
+	if (le32_to_cpu(raw_super->segment_count) > F2FS_MAX_SEGMENT) {
+		f2fs_msg(sb, KERN_INFO,
+			"Invalid segment count (%u)",
+			le32_to_cpu(raw_super->segment_count));
+		return 1;
+	}
+
 	/* check CP/SIT/NAT/SSA/MAIN_AREA area boundary */
 	if (sanity_check_area_boundary(sb, raw_super))
 		return 1;
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -269,6 +269,12 @@ struct f2fs_nat_block {
 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
 
 /*
+ * F2FS uses 4 bytes to represent block address. As a result, supported size of
+ * disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
+ */
+#define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
+
+/*
  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
  * [9:0] : valid block count


Patches currently in stable-queue which might be from jinqian@google.com are

queue-3.18/f2fs-sanity-check-segment-count.patch