diff options
| author | Hou Tao <houtao1@huawei.com> | 2021-08-20 12:45:05 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-10-07 07:53:17 +0200 |
| commit | a5a403aed8a029d71f83ce89083cf32708259f3c (patch) | |
| tree | 43dd0e7b2a2650ca5bbe13fdbec766eb24893de2 /fs | |
| parent | 68a5ca2342250886bc0c5721fe781518a58d52a7 (diff) | |
ext4: limit the number of blocks in one ADD_RANGE TLV
commit a2c2f0826e2b75560b31daf1cd9a755ab93cf4c6 upstream.
Now EXT4_FC_TAG_ADD_RANGE uses ext4_extent to track the
newly-added blocks, but the limit on the max value of
ee_len field is ignored, and it can lead to BUG_ON as
shown below when running command "fallocate -l 128M file"
on a fast_commit-enabled fs:
kernel BUG at fs/ext4/ext4_extents.h:199!
invalid opcode: 0000 [#1] SMP PTI
CPU: 3 PID: 624 Comm: fallocate Not tainted 5.14.0-rc6+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
RIP: 0010:ext4_fc_write_inode_data+0x1f3/0x200
Call Trace:
? ext4_fc_write_inode+0xf2/0x150
ext4_fc_commit+0x93b/0xa00
? ext4_fallocate+0x1ad/0x10d0
ext4_sync_file+0x157/0x340
? ext4_sync_file+0x157/0x340
vfs_fsync_range+0x49/0x80
do_fsync+0x3d/0x70
__x64_sys_fsync+0x14/0x20
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
Simply fixing it by limiting the number of blocks
in one EXT4_FC_TAG_ADD_RANGE TLV.
Fixes: aa75f4d3daae ("ext4: main fast-commit commit path")
Cc: stable@kernel.org
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210820044505.474318-1-houtao1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/fast_commit.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c index e8195229c252..782d05a3f97a 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -893,6 +893,12 @@ static int ext4_fc_write_inode_data(struct inode *inode, u32 *crc) sizeof(lrange), (u8 *)&lrange, crc)) return -ENOSPC; } else { + unsigned int max = (map.m_flags & EXT4_MAP_UNWRITTEN) ? + EXT_UNWRITTEN_MAX_LEN : EXT_INIT_MAX_LEN; + + /* Limit the number of blocks in one extent */ + map.m_len = min(max, map.m_len); + fc_ext.fc_ino = cpu_to_le32(inode->i_ino); ex = (struct ext4_extent *)&fc_ext.fc_ex; ex->ee_block = cpu_to_le32(map.m_lblk); |