Bug 2516602 (CVE-2026-72205) - CVE-2026-72205 kernel: ntfs: free volume-wide resources on fill_super failure
Summary: CVE-2026-72205 kernel: ntfs: free volume-wide resources on fill_super failure
Keywords:
Status: NEW
Alias: CVE-2026-72205
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-08-15 06:21 UTC by OSIDB Bzimport
Modified: 2026-08-18 15:22 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
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Description OSIDB Bzimport 2026-08-15 06:21:18 UTC
In the Linux kernel, the following vulnerability has been resolved:

ntfs: free volume-wide resources on fill_super failure

ntfs_fill_super()'s err_out_now path frees only the volume struct via
kfree(vol), leaving several vol-owned allocations behind on every mount
failure:

  - vol->nls_map, loaded by ntfs_init_fs_context() via
    load_nls_default() (or replaced by an explicit nls= option in
    ntfs_parse_param()), is never unload_nls()'d.

  - vol->volume_label, allocated by load_system_files() through
    ntfs_ucstonls() once the $Volume name attribute has been parsed, is
    not released by load_system_files()'s own error labels nor by the
    fill_super() inline cleanup that only runs on d_make_root()
    failure.  Any later failure inside load_system_files() leaks it.

  - vol->lcn_empty_bits_per_page was kvfree()'d in
    unl_upcase_iput_tmp_ino_err_out_now without clearing the pointer,
    so it could not be folded into a single common cleanup.

Because the failure paths never call ntfs_volume_free() and never reach
the d_make_root() inline cleanup block (it sits above the label and is
jumped over by the load_system_files() / kvmalloc failure gotos), these
resources accumulate per failed mount attempt with no chance of
recovery short of unloading the module.  This is a silent leak: the
inodes loaded prior to failure remain hashed but generic_shutdown_super()
skips evict_inodes() when sb->s_root is unset, so no CHECK_DATA_CORRUPTION
warning is emitted either.

Move the per-volume frees down to err_out_now and drop the
lcn_empty_bits_per_page kvfree() from the upper label so the cleanup is
performed exactly once on every failure path.  Using unconditional
kvfree() / kfree() / unload_nls() is safe because they all accept NULL
and the upper labels that previously freed nls_map (the d_make_root()
inline cleanup) already clear the pointer.


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