{ "data_version": "4.0", "data_type": "CVE", "data_format": "MITRE", "CVE_data_meta": { "ID": "CVE-2024-44972", "ASSIGNER": "cve@kernel.org", "STATE": "PUBLIC" }, "description": { "description_data": [ { "lang": "eng", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: do not clear page dirty inside extent_write_locked_range()\n\n[BUG]\nFor subpage + zoned case, the following workload can lead to rsv data\nleak at unmount time:\n\n # mkfs.btrfs -f -s 4k $dev\n # mount $dev $mnt\n # fsstress -w -n 8 -d $mnt -s 1709539240\n 0/0: fiemap - no filename\n 0/1: copyrange read - no filename\n 0/2: write - no filename\n 0/3: rename - no source filename\n 0/4: creat f0 x:0 0 0\n 0/4: creat add id=0,parent=-1\n 0/5: writev f0[259 1 0 0 0 0] [778052,113,965] 0\n 0/6: ioctl(FIEMAP) f0[259 1 0 0 224 887097] [1294220,2291618343991484791,0x10000] -1\n 0/7: dwrite - xfsctl(XFS_IOC_DIOINFO) f0[259 1 0 0 224 887097] return 25, fallback to stat()\n 0/7: dwrite f0[259 1 0 0 224 887097] [696320,102400] 0\n # umount $mnt\n\nThe dmesg includes the following rsv leak detection warning (all call\ntrace skipped):\n\n ------------[ cut here ]------------\n WARNING: CPU: 2 PID: 4528 at fs/btrfs/inode.c:8653 btrfs_destroy_inode+0x1e0/0x200 [btrfs]\n ---[ end trace 0000000000000000 ]---\n ------------[ cut here ]------------\n WARNING: CPU: 2 PID: 4528 at fs/btrfs/inode.c:8654 btrfs_destroy_inode+0x1a8/0x200 [btrfs]\n ---[ end trace 0000000000000000 ]---\n ------------[ cut here ]------------\n WARNING: CPU: 2 PID: 4528 at fs/btrfs/inode.c:8660 btrfs_destroy_inode+0x1a0/0x200 [btrfs]\n ---[ end trace 0000000000000000 ]---\n BTRFS info (device sda): last unmount of filesystem 1b4abba9-de34-4f07-9e7f-157cf12a18d6\n ------------[ cut here ]------------\n WARNING: CPU: 3 PID: 4528 at fs/btrfs/block-group.c:4434 btrfs_free_block_groups+0x338/0x500 [btrfs]\n ---[ end trace 0000000000000000 ]---\n BTRFS info (device sda): space_info DATA has 268218368 free, is not full\n BTRFS info (device sda): space_info total=268435456, used=204800, pinned=0, reserved=0, may_use=12288, readonly=0 zone_unusable=0\n BTRFS info (device sda): global_block_rsv: size 0 reserved 0\n BTRFS info (device sda): trans_block_rsv: size 0 reserved 0\n BTRFS info (device sda): chunk_block_rsv: size 0 reserved 0\n BTRFS info (device sda): delayed_block_rsv: size 0 reserved 0\n BTRFS info (device sda): delayed_refs_rsv: size 0 reserved 0\n ------------[ cut here ]------------\n WARNING: CPU: 3 PID: 4528 at fs/btrfs/block-group.c:4434 btrfs_free_block_groups+0x338/0x500 [btrfs]\n ---[ end trace 0000000000000000 ]---\n BTRFS info (device sda): space_info METADATA has 267796480 free, is not full\n BTRFS info (device sda): space_info total=268435456, used=131072, pinned=0, reserved=0, may_use=262144, readonly=0 zone_unusable=245760\n BTRFS info (device sda): global_block_rsv: size 0 reserved 0\n BTRFS info (device sda): trans_block_rsv: size 0 reserved 0\n BTRFS info (device sda): chunk_block_rsv: size 0 reserved 0\n BTRFS info (device sda): delayed_block_rsv: size 0 reserved 0\n BTRFS info (device sda): delayed_refs_rsv: size 0 reserved 0\n\nAbove $dev is a tcmu-runner emulated zoned HDD, which has a max zone\nappend size of 64K, and the system has 64K page size.\n\n[CAUSE]\nI have added several trace_printk() to show the events (header skipped):\n\n > btrfs_dirty_pages: r/i=5/259 dirty start=774144 len=114688\n > btrfs_dirty_pages: r/i=5/259 dirty part of page=720896 off_in_page=53248 len_in_page=12288\n > btrfs_dirty_pages: r/i=5/259 dirty part of page=786432 off_in_page=0 len_in_page=65536\n > btrfs_dirty_pages: r/i=5/259 dirty part of page=851968 off_in_page=0 len_in_page=36864\n\nThe above lines show our buffered write has dirtied 3 pages of inode\n259 of root 5:\n\n 704K 768K 832K 896K\n I |////I/////////////////I///////////| I\n 756K 868K\n\n |///| is the dirtied range using subpage bitmaps. and 'I' is the page\n boundary.\n\n Meanwhile all three pages (704K, 768K, 832K) have their PageDirty\n flag set.\n\n > btrfs_direct_write: r/i=5/259 start dio filepos=696320 len=102400\n\nThen direct IO writ\n---truncated---" } ] }, "problemtype": { "problemtype_data": [ { "description": [ { "lang": "eng", "value": "n/a" } ] } ] }, "affects": { "vendor": { "vendor_data": [ { "vendor_name": "Linux", "product": { "product_data": [ { "product_name": "Linux", "version": { "version_data": [ { "version_affected": "<", "version_name": "1da177e4c3f4", "version_value": "ba4dedb71356" }, { "version_value": "not down converted", "x_cve_json_5_version_data": { "versions": [ { "version": "6.6.46", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "custom" }, { "version": "6.10.5", "lessThanOrEqual": "6.10.*", "status": "unaffected", "versionType": "custom" }, { "version": "6.11", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ], "defaultStatus": "affected" } } ] } } ] } } ] } }, "references": { "reference_data": [ { "url": "https://git.kernel.org/stable/c/ba4dedb71356638d8284e34724daca944be70368", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/ba4dedb71356638d8284e34724daca944be70368" }, { "url": "https://git.kernel.org/stable/c/d3b403209f767e5857c1b9fda66726e6e6ffc99f", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/d3b403209f767e5857c1b9fda66726e6e6ffc99f" }, { "url": "https://git.kernel.org/stable/c/97713b1a2ced1e4a2a6c40045903797ebd44d7e0", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/97713b1a2ced1e4a2a6c40045903797ebd44d7e0" } ] }, "generator": { "engine": "bippy-c9c4e1df01b2" } }