CVE-2026-98843 PUBLISHED

netfs: zero gaps in read-gaps folio to avoid writing back stale data

Assigner: Linux
Reserved: 25.09.2026 Published: 18.10.2026 Updated: 18.10.2026

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

netfs: zero gaps in read-gaps folio to avoid writing back stale data

netfs_read_gaps() leaves gaps around a streaming write's dirty region unread on the server side, so a short/EOF response there left stale folio content that later got written back.

Zero it after the read completes, not before: netfs_wait_for_read() returns rreq->transferred once ret >= 0, so build an iterator over the same bvec array the read used, advance past ret, and zero the rest. The dirty region already maps to sink pages in that array rather than the real folio, so this can't touch it, and only the actual shortfall gets zeroed instead of the whole gap upfront.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from ee4cdf7ba857a894ad1650d6ab77669cbbfa329e to 512eaf01ffabf4258e945016b50df5aed940b705 (excl.)
  • affected from ee4cdf7ba857a894ad1650d6ab77669cbbfa329e to 2a62fe628a877c249c8286b157ee99d82840d9dc (excl.)
  • affected from ee4cdf7ba857a894ad1650d6ab77669cbbfa329e to 8db55c5cd831a786a1a2a2d391aa80354535a353 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 6.12 is affected
  • unaffected from 0 to 6.12 (excl.)
  • unaffected from 6.18.56 to 6.18.* (incl.)
  • unaffected from 7.2.10 to 7.2.* (incl.)
  • unaffected from 7.3-rc6 to * (incl.)

References