CVE-2025-38716

What the bug is

The hfs_find_init() method can trigger the crash if tree pointer is NULL: [ 45.746290][ T9787] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000008: 0000 [#1] SMP KAI [ 45.747287][ T9787] KASAN: null-ptr-deref in range [0x0000000000000040-0x0000000000000047] [ 45.748716][ T9787] CPU: 2 UID: 0 PID: 9787 Comm: repro Not tainted 6.16.0-rc3 #10 PREEMPT(full) [ 45.750250][ T9787] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 45.751983][ T9787] RIP: 0010:hfs_find_init+0x86/0x230 [ 45.752834][ T9787] Code: c1 ea 03 80 3c 02 00 0f 85 9a 01 00 00 4c 8d 6b 40 48 c7 45 18 00 00 00 00 48 b8 00 00 00 00 00 fc [ 45.755574][ T9787] RSP: 0018:ffffc90015157668 EFLAGS: 00010202 [ 45.756432][ T9787] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff819a4d09 [ 45.757457][ T9787] RDX: 0000000000000008 RSI: ffffffff819acd3a RDI: ffffc900151576e8 [ 45.758282][ T9787] RBP: ffffc900151576d0 R08: 0000000000000005 R09: 0000000000000000 [ 45.758943][ T9787] R10: 0000000080000000 R11: 0000000000000001 R12: 0000000000000004 [ 45.759619][ T9787] R13: 0000000000000040 R14: ffff88802c50814a R15: 0000000000000000 [ 45.760293][ T9787] FS: 00007ffb72734540(0000) GS:ffff8880cec64000(0000) knlGS:0000000000000000 [ 45.761050][ T9787] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 45.761606][ T9787] CR2: 00007f9bd8225000 CR3: 000000010979a000 CR4: 00000000000006f0 [ 45.762286][ T9787] Call Trace: [ 45.762570][ T9787] <TASK> [ 45.762824][ T9787] hfs_ext_read_extent+0x190/0x9d0 [ 45.763269][ T9787] ? submit_bio_noacct_nocheck+0x2dd/0xce0 [ 45.763766][ T9787] ? __pfx_hfs_ext_read_extent+0x10/0x10 [ 45.764250][ T9787] hfs_get_block+0x55f/0x830 [ 45.764646][ T9787] block_read_full_folio+0x36d/0x850 [ 45.765105][ T9787] ? __pfx_hfs_get_block+0x10/0x10 [ 45.765541][ T9787] ? const_folio_flags+0x5b/0x100 [ 45.765972][ T9787] ? __pfx_hfs_read_folio+0x10/0x10 [ 45.766415][ T9787] filemap_read_folio+0xbe/0x290 [ 45.766840][ T9787] ? __pfx_filemap_read_folio+0x10/0x10 [ 45.767325][ T9787] ? __filemap_get_folio+0x32b/0xbf0 [ 45.767780][ T9787] do_read_cache_folio+0x263/0x5c0 [ 45.768223][ T9787] ? __pfx_hfs_read_folio+0x10/0x10 [ 45.768666][ T9787] read_cache_page+0x5b/0x160 [ 45.769070][ T9787] hfs_btree_open+0x491/0x1740 [ 45.769481][ T9787] hfs_mdb_get+0x15e2/0x1fb0 [ 45.769877][ T9787] ? __pfx_hfs_mdb_get+0x10/0x10 [ 45.770316][ T9787] ? find_held_lock+0x2b/0x80 [ 45.770731][ T9787] ? lockdep_init_map_type+0x5c/0x280 [ 45.771200][ T9787] ? lockdep_init_map_type+0x5c/0x280 [ 45.771674][ T9787] hfs_fill_super+0x38e/0x720 [ 45.772092][ T9787] ? __pfx_hfs_fill_super+0x10/0x10 [ 45.772549][ T9787] ? snprintf+0xbe/0x100 [ 45.772931][ T9787] ? __pfx_snprintf+0x10/0x10 [ 45.773350][ T9787] ? do_raw_spin_lock+0x129/0x2b0 [ 45.773796][ T9787] ? find_held_lock+0x2b/0x80 [ 45.774215][ T9787] ? set_blocksize+0x40a/0x510 [ 45.774636][ T9787] ? sb_set_blocksize+0x176/0x1d0 [ 45.775087][ T9787] ? setup_bdev_super+0x369/0x730 [ 45.775533][ T9787] get_tree_bdev_flags+0x384/0x620 [ 45.775985][ T9787] ? __pfx_hfs_fill_super+0x10/0x10 [ 45.776453][ T9787] ? __pfx_get_tree_bdev_flags+0x10/0x10 [ 45.776950][ T9787] ? bpf_lsm_capable+0x9/0x10 [ 45.777365][ T9787] ? security_capable+0x80/0x260 [ 45.777803][ T9787] vfs_get_tree+0x8e/0x340 [ 45.778203][ T9787] path_mount+0x13de/0x2010 [ 45.778604][ T9787] ? kmem_cache_free+0x2b0/0x4c0 [ 45.779052][ T9787] ? __pfx_path_mount+0x10/0x10 [ 45.779480][ T9787] ? getname_flags.part.0+0x1c5/0x550 [ 45.779954][ T9787] ? putname+0x154/0x1a0 [ 45.780335][ T9787] __x64_sys_mount+0x27b/0x300 [ 45.780758][ T9787] ? __pfx___x64_sys_mount+0x10/0x10 [ 45.781232][ T9787] ---truncated---

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

fs/hfs/bfind.c
fs/hfs/btree.c
fs/hfs/extent.c
fs/hfs/hfs_fs.h

What this is

HFS FILESYSTEMMAINTAINERS section matched on fs/hfs/ · linux-fsdevel@vger.kernel.org · Maintained

Kernel module

hfs

Check it on the machine

grep -w CONFIG_HFS_FS /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w hfs

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookworm, trixie, forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

a module where it is built at all; some flavours do not build it

Build switch

CONFIG_HFS_FS

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2025-09-04 (13 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.15%, higher than 3.6% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

fs/hfs

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
3.2	6.6.103	4f032979b63a
3.2	6.12.43	5d8b24952736
3.2	6.15.11	b918c17a1934
3.2	6.16.2	6e20e10064fd
3.2	6.17	736a0516a162
2.6.27.60	0	0
2.6.32.51	0	0
2.6.34.14	0	0
3.0.14	0	0
3.1.6	0	0