From cdce59a1549190b66f8e3fe465c2b2f714b98a94 Mon Sep 17 00:00:00 2001 From: Ritesh Harjani Date: Mon, 17 Jan 2022 17:41:49 +0530 Subject: [PATCH] ext4: fix error handling in ext4_fc_record_modified_inode() 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 Suggested-by: Lukas Czerner Signed-off-by: Ritesh Harjani Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/62e8b6a1cce9359682051deb736a3c0953c9d1e9.1642416995.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org --- 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 ccd2b216d6ba..5934c23e153e 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -1410,14 +1410,15 @@ 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; @@ -1449,7 +1450,9 @@ 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)); @@ -1649,6 +1652,8 @@ 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); @@ -1666,18 +1671,14 @@ 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( @@ -1691,10 +1692,8 @@ 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; } @@ -1707,10 +1706,8 @@ 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 @@ -1730,10 +1727,8 @@ 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. @@ -1745,6 +1740,7 @@ next: } ext4_ext_replay_shrink_inode(inode, i_size_read(inode) >> sb->s_blocksize_bits); +out: iput(inode); return 0; } @@ -1774,6 +1770,8 @@ 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), @@ -1783,10 +1781,8 @@ 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; @@ -1801,15 +1797,13 @@ 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; } -- 2.11.0