Current code does not fully takes care of krealloc() error case,
which could lead to silent memory corruption or a kernel bug.
This patch fixes that.
Also it cleans up some duplicated error handling logic from various functions
in fast_commit.c file.
Reported-by: luo penghao <luo.penghao@xxxxxxxxxx>
Suggested-by: Lukas Czerner <lczerner@xxxxxxxxxx>
Signed-off-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
---
fs/ext4/fast_commit.c | 64 ++++++++++++++++++++-----------------------
1 file changed, 29 insertions(+), 35 deletions(-)
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index 5ae8026a0c56..4541c8468c01 100644
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -1392,14 +1392,15 @@ static int ext4_fc_record_modified_inode(struct super_block *sb, int ino)
if (state->fc_modified_inodes[i] == ino)
return 0;
if (state->fc_modified_inodes_used == state->fc_modified_inodes_size) {
- state->fc_modified_inodes_size +=
- EXT4_FC_REPLAY_REALLOC_INCREMENT;
state->fc_modified_inodes = krealloc(
- state->fc_modified_inodes, sizeof(int) *
- state->fc_modified_inodes_size,
- GFP_KERNEL);
+ state->fc_modified_inodes,
+ sizeof(int) * (state->fc_modified_inodes_size +
+ EXT4_FC_REPLAY_REALLOC_INCREMENT),
+ GFP_KERNEL);
if (!state->fc_modified_inodes)
return -ENOMEM;
+ state->fc_modified_inodes_size +=
+ EXT4_FC_REPLAY_REALLOC_INCREMENT;
}
state->fc_modified_inodes[state->fc_modified_inodes_used++] = ino;
return 0;
@@ -1431,7 +1432,9 @@ static int ext4_fc_replay_inode(struct super_block *sb, struct ext4_fc_tl *tl,
}
inode = NULL;
- ext4_fc_record_modified_inode(sb, ino);
+ ret = ext4_fc_record_modified_inode(sb, ino);
+ if (ret)
+ goto out;
raw_fc_inode = (struct ext4_inode *)
(val + offsetof(struct ext4_fc_inode, fc_raw_inode));
@@ -1621,6 +1624,8 @@ static int ext4_fc_replay_add_range(struct super_block *sb,
}
ret = ext4_fc_record_modified_inode(sb, inode->i_ino);
+ if (ret)
+ goto out;
start = le32_to_cpu(ex->ee_block);
start_pblk = ext4_ext_pblock(ex);
@@ -1638,18 +1643,14 @@ static int ext4_fc_replay_add_range(struct super_block *sb,
map.m_pblk = 0;
ret = ext4_map_blocks(NULL, inode, &map, 0);
- if (ret < 0) {
- iput(inode);
- return 0;
- }
+ if (ret < 0)
+ goto out;
if (ret == 0) {
/* Range is not mapped */
path = ext4_find_extent(inode, cur, NULL, 0);
- if (IS_ERR(path)) {
- iput(inode);
- return 0;
- }
+ if (IS_ERR(path))
+ goto out;
memset(&newex, 0, sizeof(newex));
newex.ee_block = cpu_to_le32(cur);
ext4_ext_store_pblock(
@@ -1663,10 +1664,8 @@ static int ext4_fc_replay_add_range(struct super_block *sb,
up_write((&EXT4_I(inode)->i_data_sem));
ext4_ext_drop_refs(path);
kfree(path);
- if (ret) {
- iput(inode);
- return 0;
- }
+ if (ret)
+ goto out;
goto next;
}
@@ -1679,10 +1678,8 @@ static int ext4_fc_replay_add_range(struct super_block *sb,
ret = ext4_ext_replay_update_ex(inode, cur, map.m_len,
ext4_ext_is_unwritten(ex),
start_pblk + cur - start);
- if (ret) {
- iput(inode);
- return 0;
- }
+ if (ret)
+ goto out;
/*
* Mark the old blocks as free since they aren't used
* anymore. We maintain an array of all the modified
@@ -1702,10 +1699,8 @@ static int ext4_fc_replay_add_range(struct super_block *sb,
ext4_ext_is_unwritten(ex), map.m_pblk);
ret = ext4_ext_replay_update_ex(inode, cur, map.m_len,
ext4_ext_is_unwritten(ex), map.m_pblk);
- if (ret) {
- iput(inode);
- return 0;
- }
+ if (ret)
+ goto out;
/*
* We may have split the extent tree while toggling the state.
* Try to shrink the extent tree now.
@@ -1717,6 +1712,7 @@ static int ext4_fc_replay_add_range(struct super_block *sb,
}
ext4_ext_replay_shrink_inode(inode, i_size_read(inode) >>
sb->s_blocksize_bits);
+out:
iput(inode);
return 0;
}
@@ -1746,6 +1742,8 @@ ext4_fc_replay_del_range(struct super_block *sb, struct ext4_fc_tl *tl,
}
ret = ext4_fc_record_modified_inode(sb, inode->i_ino);
+ if (ret)
+ goto out;
jbd_debug(1, "DEL_RANGE, inode %ld, lblk %d, len %d\n",
inode->i_ino, le32_to_cpu(lrange.fc_lblk),
@@ -1755,10 +1753,8 @@ ext4_fc_replay_del_range(struct super_block *sb, struct ext4_fc_tl *tl,
map.m_len = remaining;
ret = ext4_map_blocks(NULL, inode, &map, 0);
- if (ret < 0) {
- iput(inode);
- return 0;
- }
+ if (ret < 0)
+ goto out;
if (ret > 0) {
remaining -= ret;
cur += ret;
@@ -1773,15 +1769,13 @@ ext4_fc_replay_del_range(struct super_block *sb, struct ext4_fc_tl *tl,
ret = ext4_ext_remove_space(inode, lrange.fc_lblk,
lrange.fc_lblk + lrange.fc_len - 1);
up_write(&EXT4_I(inode)->i_data_sem);
- if (ret) {
- iput(inode);
- return 0;
- }
+ if (ret)
+ goto out;
ext4_ext_replay_shrink_inode(inode,
i_size_read(inode) >> sb->s_blocksize_bits);
ext4_mark_inode_dirty(NULL, inode);
+out:
iput(inode);
-
return 0;
}
--
2.31.1
