CVE-2025-68794

Summary

In the Linux kernel, the following vulnerability has been resolved:

iomap: adjust read range correctly for non-block-aligned positions

iomap_adjust_read_range() assumes that the position and length passed in are block-aligned. This is not always the case however, as shown in the syzbot generated case for erofs. This causes too many bytes to be skipped for uptodate blocks, which results in returning the incorrect position and length to read in. If all the blocks are uptodate, this underflows length and returns a position beyond the folio.

Fix the calculation to also take into account the block offset when calculating how many bytes can be skipped for uptodate blocks.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux9dc55f1389f9569acf9659e58dd836a9c70df217 < 82b60ffbb532d919959702768dca04c3c0500ae5affected
LinuxLinux9dc55f1389f9569acf9659e58dd836a9c70df217 < 12053695c8ef5410e8cc6c9ed4c0db9cd9c82b3eaffected
LinuxLinux9dc55f1389f9569acf9659e58dd836a9c70df217 < 142194fb21afe964d2d194cab1fc357cbf87e899affected
LinuxLinux9dc55f1389f9569acf9659e58dd836a9c70df217 < 7aa6bc3e8766990824f66ca76c19596ce10daf3eaffected
LinuxLinux4.19affected
LinuxLinux0 < 4.19unaffected
LinuxLinux6.6.120 <= 6.6.*unaffected
LinuxLinux6.12.64 <= 6.12.*unaffected
LinuxLinux6.18.3 <= 6.18.*unaffected
LinuxLinux6.19 <= *unaffected

Weaknesses

References