5.15-stable patches

added patches:
	nilfs2-fix-underflow-in-second-superblock-position-calculations.patch

diff --git a/queue-5.15/nilfs2-fix-underflow-in-second-superblock-position-calculations.patch b/queue-5.15/nilfs2-fix-underflow-in-second-superblock-position-calculations.patch
new file mode 100644 (file)
index 0000000..2aea697
--- /dev/null
+++ b/queue-5.15/nilfs2-fix-underflow-in-second-superblock-position-calculations.patch
@@ -0,0 +1,136 @@
+From 99b9402a36f0799f25feee4465bfa4b8dfa74b4d Mon Sep 17 00:00:00 2001
+From: Ryusuke Konishi <konishi.ryusuke@gmail.com>
+Date: Wed, 15 Feb 2023 07:40:43 +0900
+Subject: nilfs2: fix underflow in second superblock position calculations
+
+From: Ryusuke Konishi <konishi.ryusuke@gmail.com>
+
+commit 99b9402a36f0799f25feee4465bfa4b8dfa74b4d upstream.
+
+Macro NILFS_SB2_OFFSET_BYTES, which computes the position of the second
+superblock, underflows when the argument device size is less than 4096
+bytes.  Therefore, when using this macro, it is necessary to check in
+advance that the device size is not less than a lower limit, or at least
+that underflow does not occur.
+
+The current nilfs2 implementation lacks this check, causing out-of-bound
+block access when mounting devices smaller than 4096 bytes:
+
+ I/O error, dev loop0, sector 36028797018963960 op 0x0:(READ) flags 0x0
+ phys_seg 1 prio class 2
+ NILFS (loop0): unable to read secondary superblock (blocksize = 1024)
+
+In addition, when trying to resize the filesystem to a size below 4096
+bytes, this underflow occurs in nilfs_resize_fs(), passing a huge number
+of segments to nilfs_sufile_resize(), corrupting parameters such as the
+number of segments in superblocks.  This causes excessive loop iterations
+in nilfs_sufile_resize() during a subsequent resize ioctl, causing
+semaphore ns_segctor_sem to block for a long time and hang the writer
+thread:
+
+ INFO: task segctord:5067 blocked for more than 143 seconds.
+      Not tainted 6.2.0-rc8-syzkaller-00015-gf6feea56f66d #0
+ "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
+ task:segctord        state:D stack:23456 pid:5067  ppid:2
+ flags:0x00004000
+ Call Trace:
+  <TASK>
+  context_switch kernel/sched/core.c:5293 [inline]
+  __schedule+0x1409/0x43f0 kernel/sched/core.c:6606
+  schedule+0xc3/0x190 kernel/sched/core.c:6682
+  rwsem_down_write_slowpath+0xfcf/0x14a0 kernel/locking/rwsem.c:1190
+  nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357
+  nilfs_segctor_thread_construct fs/nilfs2/segment.c:2486 [inline]
+  nilfs_segctor_thread+0x52f/0x1140 fs/nilfs2/segment.c:2570
+  kthread+0x270/0x300 kernel/kthread.c:376
+  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
+  </TASK>
+ ...
+ Call Trace:
+  <TASK>
+  folio_mark_accessed+0x51c/0xf00 mm/swap.c:515
+  __nilfs_get_page_block fs/nilfs2/page.c:42 [inline]
+  nilfs_grab_buffer+0x3d3/0x540 fs/nilfs2/page.c:61
+  nilfs_mdt_submit_block+0xd7/0x8f0 fs/nilfs2/mdt.c:121
+  nilfs_mdt_read_block+0xeb/0x430 fs/nilfs2/mdt.c:176
+  nilfs_mdt_get_block+0x12d/0xbb0 fs/nilfs2/mdt.c:251
+  nilfs_sufile_get_segment_usage_block fs/nilfs2/sufile.c:92 [inline]
+  nilfs_sufile_truncate_range fs/nilfs2/sufile.c:679 [inline]
+  nilfs_sufile_resize+0x7a3/0x12b0 fs/nilfs2/sufile.c:777
+  nilfs_resize_fs+0x20c/0xed0 fs/nilfs2/super.c:422
+  nilfs_ioctl_resize fs/nilfs2/ioctl.c:1033 [inline]
+  nilfs_ioctl+0x137c/0x2440 fs/nilfs2/ioctl.c:1301
+  ...
+
+This fixes these issues by inserting appropriate minimum device size
+checks or anti-underflow checks, depending on where the macro is used.
+
+Link: https://lkml.kernel.org/r/0000000000004e1dfa05f4a48e6b@google.com
+Link: https://lkml.kernel.org/r/20230214224043.24141-1-konishi.ryusuke@gmail.com
+Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
+Reported-by: <syzbot+f0c4082ce5ebebdac63b@syzkaller.appspotmail.com>
+Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
+Cc: <stable@vger.kernel.org>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/nilfs2/ioctl.c     |    7 +++++++
+ fs/nilfs2/super.c     |    9 +++++++++
+ fs/nilfs2/the_nilfs.c |    8 +++++++-
+ 3 files changed, 23 insertions(+), 1 deletion(-)
+
+--- a/fs/nilfs2/ioctl.c
++++ b/fs/nilfs2/ioctl.c
+@@ -1114,7 +1114,14 @@ static int nilfs_ioctl_set_alloc_range(s
+ 
+       minseg = range[0] + segbytes - 1;
+       do_div(minseg, segbytes);
++
++      if (range[1] < 4096)
++              goto out;
++
+       maxseg = NILFS_SB2_OFFSET_BYTES(range[1]);
++      if (maxseg < segbytes)
++              goto out;
++
+       do_div(maxseg, segbytes);
+       maxseg--;
+ 
+--- a/fs/nilfs2/super.c
++++ b/fs/nilfs2/super.c
+@@ -409,6 +409,15 @@ int nilfs_resize_fs(struct super_block *
+               goto out;
+ 
+       /*
++       * Prevent underflow in second superblock position calculation.
++       * The exact minimum size check is done in nilfs_sufile_resize().
++       */
++      if (newsize < 4096) {
++              ret = -ENOSPC;
++              goto out;
++      }
++
++      /*
+        * Write lock is required to protect some functions depending
+        * on the number of segments, the number of reserved segments,
+        * and so forth.
+--- a/fs/nilfs2/the_nilfs.c
++++ b/fs/nilfs2/the_nilfs.c
+@@ -544,9 +544,15 @@ static int nilfs_load_super_block(struct
+ {
+       struct nilfs_super_block **sbp = nilfs->ns_sbp;
+       struct buffer_head **sbh = nilfs->ns_sbh;
+-      u64 sb2off = NILFS_SB2_OFFSET_BYTES(nilfs->ns_bdev->bd_inode->i_size);
++      u64 sb2off, devsize = nilfs->ns_bdev->bd_inode->i_size;
+       int valid[2], swp = 0;
+ 
++      if (devsize < NILFS_SEG_MIN_BLOCKS * NILFS_MIN_BLOCK_SIZE + 4096) {
++              nilfs_err(sb, "device size too small");
++              return -EINVAL;
++      }
++      sb2off = NILFS_SB2_OFFSET_BYTES(devsize);
++
+       sbp[0] = nilfs_read_super_block(sb, NILFS_SB_OFFSET_BYTES, blocksize,
+                                       &sbh[0]);
+       sbp[1] = nilfs_read_super_block(sb, sb2off, blocksize, &sbh[1]);

diff --git a/queue-5.15/series b/queue-5.15/series
index d82fbffaa5f265cbafdc7ef1f842cef238f62053..b00b63edcb053362899deae395b1c2d933f4dd64 100644 (file)
--- a/queue-5.15/series
+++ b/queue-5.15/series
@@ -68,3 +68,4 @@ net-mpls-fix-stale-pointer-if-allocation-fails-during-device-rename.patch
 ixgbe-add-double-of-vlan-header-when-computing-the-max-mtu.patch
 ipv6-fix-datagram-socket-connection-with-dscp.patch
 ipv6-fix-tcp-socket-connection-with-dscp.patch
+nilfs2-fix-underflow-in-second-superblock-position-calculations.patch