CVE-2024-50015: ext4: dax: fix overflowing extents beyond inode size when partially writing
Vulnerability summary
CVE-2024-50015 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 15.1% of scored vulnerabilities.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 35 · Related 32Timeline
- 21-10-2024PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: ext4: dax: fix overflowing extents beyond inode size when partially writing The dax_iomap_rw() does two things in each iteration: map written blocks and copy user data to blocks. If the process is killed by user(See signal handling in dax_iomap_iter()), the copied data will be returned and added on inode size, which means that the length of written extents may exceed the inode size, then fsck will fail. An example is given as: dd if=/dev/urandom of=file bs=4M count=1 dax_iomap_rw iomap_iter // round 1 ext4_iomap_begin ext4_iomap_alloc // allocate 0~2M extents(written flag) dax_iomap_iter // copy 2M data iomap_iter // round 2 iomap_iter_advance iter->pos += iter->processed // iter->pos = 2M ext4_iomap_begin ext4_iomap_alloc // allocate 2~4M extents(written flag) dax_iomap_iter fatal_signal_pending done = iter->pos - iocb->ki_pos // done = 2M ext4_handle_inode_extension ext4_update_inode_size // inode size = 2M fsck reports: Inode 13, i_size is 2097152, should be 4194304. Fix? Fix the problem by truncating extents if the written length is smaller than expected.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.24%
Chance of exploitation in the next 30 days
Percentile
15%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.24% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu133 products
- linuxAll versions (No fix recorded) | < 5.15.0-127.137 | < 6.8.0-54.56
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.15.0-1073.79 | < 6.8.0-1023.25
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 776722e85d3b0936253ecc3d14db4fba37f191ba, < f8a7c342326f6ad1dfdb30a18dd013c70f5e9669 | ≥ 776722e85d3b0936253ecc3d14db4fba37f191ba, < 8c30a9a8610c314554997f86370140746aa35661 | ≥ 776722e85d3b0936253ecc3d14db4fba37f191ba, < abfaa876b948baaea4d14f21a1963789845c8b4c | ≥ 776722e85d3b0936253ecc3d14db4fba37f191ba, < 5efccdee4a7d507a483f20f880b809cc4eaef14d | ≥ 776722e85d3b0936253ecc3d14db4fba37f191ba, < a9f331f51515bdb3ebc8d0963131af367ef468f6 | ≥ 776722e85d3b0936253ecc3d14db4fba37f191ba, < ec0dd451e236c46e4858d53e9e82bae7797a7af5 | ≥ 776722e85d3b0936253ecc3d14db4fba37f191ba, < dda898d7ffe85931f9cca6d702a51f33717c501e | 4.10
- linux_kernel≥ 4.10, < 5.10.227 | ≥ 5.11, < 5.15.168 | ≥ 5.16, < 6.1.113 | ≥ 6.2, < 6.6.55 | ≥ 6.7, < 6.10.14 | ≥ 6.11, < 6.11.3
Debian1 product
- linux< 6.1.115-1 | < 6.11.4-1
3 vendors · 136 products
