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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-25 15:55:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-25 15:55:03 -0700 |
| commit | 75467f60a3d14f08f86f2b353298d2826382ff23 (patch) | |
| tree | acd8a7d5b5a675042449386efa5b42ec44d8bf81 /fs/ext4/bitmap.c | |
| download | linux-stable-75467f60a3d14f08f86f2b353298d2826382ff23.tar.gz linux-stable-75467f60a3d14f08f86f2b353298d2826382ff23.zip | |
Merge tag 'ipe-pr-20260925' of git://git.kernel.org/pub/scm/linux/kernel/git/wufan/ipegrafted
Pull IPE fixes from Fan Wu:
"Two fixes for use-after-free issues found by recent LLM-assisted code
analysis.
- move successful policy load auditing under the new policy
directory's inode lock, preventing a concurrent policy deletion
from freeing the policy while it is still being audited
- protect the dm-verity root hash with RCU, preventing policy
evaluation from racing with root hash replacement during preresume"
* tag 'ipe-pr-20260925' of git://git.kernel.org/pub/scm/linux/kernel/git/wufan/ipe:
ipe: protect the dm-verity root hash with RCU
ipe: fix use-after-free when auditing a newly loaded policy
Diffstat (limited to 'fs/ext4/bitmap.c')
| -rw-r--r-- | fs/ext4/bitmap.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/fs/ext4/bitmap.c b/fs/ext4/bitmap.c new file mode 100644 index 000000000..87760fabd --- /dev/null +++ b/fs/ext4/bitmap.c @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/fs/ext4/bitmap.c + * + * Copyright (C) 1992, 1993, 1994, 1995 + * Remy Card (card@masi.ibp.fr) + * Laboratoire MASI - Institut Blaise Pascal + * Universite Pierre et Marie Curie (Paris VI) + */ + +#include <linux/buffer_head.h> +#include "ext4.h" + +unsigned int ext4_count_free(char *bitmap, unsigned int numchars) +{ + return numchars * BITS_PER_BYTE - memweight(bitmap, numchars); +} + +int ext4_inode_bitmap_csum_verify(struct super_block *sb, + struct ext4_group_desc *gdp, + struct buffer_head *bh) +{ + __u32 hi; + __u32 provided, calculated; + struct ext4_sb_info *sbi = EXT4_SB(sb); + int sz; + + if (!ext4_has_feature_metadata_csum(sb)) + return 1; + + sz = EXT4_INODES_PER_GROUP(sb) >> 3; + provided = le16_to_cpu(gdp->bg_inode_bitmap_csum_lo); + calculated = ext4_chksum(sbi->s_csum_seed, (__u8 *)bh->b_data, sz); + if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END) { + hi = le16_to_cpu(gdp->bg_inode_bitmap_csum_hi); + provided |= (hi << 16); + } else + calculated &= 0xFFFF; + + return provided == calculated; +} + +void ext4_inode_bitmap_csum_set(struct super_block *sb, + struct ext4_group_desc *gdp, + struct buffer_head *bh) +{ + __u32 csum; + struct ext4_sb_info *sbi = EXT4_SB(sb); + int sz; + + if (!ext4_has_feature_metadata_csum(sb)) + return; + + sz = EXT4_INODES_PER_GROUP(sb) >> 3; + csum = ext4_chksum(sbi->s_csum_seed, (__u8 *)bh->b_data, sz); + gdp->bg_inode_bitmap_csum_lo = cpu_to_le16(csum & 0xFFFF); + if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END) + gdp->bg_inode_bitmap_csum_hi = cpu_to_le16(csum >> 16); +} + +int ext4_block_bitmap_csum_verify(struct super_block *sb, + struct ext4_group_desc *gdp, + struct buffer_head *bh) +{ + __u32 hi; + __u32 provided, calculated; + struct ext4_sb_info *sbi = EXT4_SB(sb); + int sz = EXT4_CLUSTERS_PER_GROUP(sb) / 8; + + if (!ext4_has_feature_metadata_csum(sb)) + return 1; + + provided = le16_to_cpu(gdp->bg_block_bitmap_csum_lo); + calculated = ext4_chksum(sbi->s_csum_seed, (__u8 *)bh->b_data, sz); + if (sbi->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_END) { + hi = le16_to_cpu(gdp->bg_block_bitmap_csum_hi); + provided |= (hi << 16); + } else + calculated &= 0xFFFF; + + return provided == calculated; +} + +void ext4_block_bitmap_csum_set(struct super_block *sb, + struct ext4_group_desc *gdp, + struct buffer_head *bh) +{ + int sz = EXT4_CLUSTERS_PER_GROUP(sb) / 8; + __u32 csum; + struct ext4_sb_info *sbi = EXT4_SB(sb); + + if (!ext4_has_feature_metadata_csum(sb)) + return; + + csum = ext4_chksum(sbi->s_csum_seed, (__u8 *)bh->b_data, sz); + gdp->bg_block_bitmap_csum_lo = cpu_to_le16(csum & 0xFFFF); + if (sbi->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_END) + gdp->bg_block_bitmap_csum_hi = cpu_to_le16(csum >> 16); +} |
