CVE-2025-38714

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

hfsplus: fix slab-out-of-bounds in hfsplus_bnode_read()

The hfsplus_bnode_read() method can trigger the issue:

[ 174.852007][ T9784] ================================================================== [ 174.852709][ T9784] BUG: KASAN: slab-out-of-bounds in hfsplus_bnode_read+0x2f4/0x360 [ 174.853412][ T9784] Read of size 8 at addr ffff88810b5fc6c0 by task repro/9784 [ 174.854059][ T9784] [ 174.854272][ T9784] CPU: 1 UID: 0 PID: 9784 Comm: repro Not tainted 6.16.0-rc3 #7 PREEMPT(full) [ 174.854281][ T9784] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 174.854286][ T9784] Call Trace: [ 174.854289][ T9784] [ 174.854292][ T9784] dump_stack_lvl+0x10e/0x1f0 [ 174.854305][ T9784] print_report+0xd0/0x660 [ 174.854315][ T9784] ? __virt_addr_valid+0x81/0x610 [ 174.854323][ T9784] ? __phys_addr+0xe8/0x180 [ 174.854330][ T9784] ? hfsplus_bnode_read+0x2f4/0x360 [ 174.854337][ T9784] kasan_report+0xc6/0x100 [ 174.854346][ T9784] ? hfsplus_bnode_read+0x2f4/0x360 [ 174.854354][ T9784] hfsplus_bnode_read+0x2f4/0x360 [ 174.854362][ T9784] hfsplus_bnode_dump+0x2ec/0x380 [ 174.854370][ T9784] ? __pfx_hfsplus_bnode_dump+0x10/0x10 [ 174.854377][ T9784] ? hfsplus_bnode_write_u16+0x83/0xb0 [ 174.854385][ T9784] ? srcu_gp_start+0xd0/0x310 [ 174.854393][ T9784] ? __mark_inode_dirty+0x29e/0xe40 [ 174.854402][ T9784] hfsplus_brec_remove+0x3d2/0x4e0 [ 174.854411][ T9784] __hfsplus_delete_attr+0x290/0x3a0 [ 174.854419][ T9784] ? __pfx_hfs_find_1st_rec_by_cnid+0x10/0x10 [ 174.854427][ T9784] ? __pfx___hfsplus_delete_attr+0x10/0x10 [ 174.854436][ T9784] ? __asan_memset+0x23/0x50 [ 174.854450][ T9784] hfsplus_delete_all_attrs+0x262/0x320 [ 174.854459][ T9784] ? __pfx_hfsplus_delete_all_attrs+0x10/0x10 [ 174.854469][ T9784] ? rcu_is_watching+0x12/0xc0 [ 174.854476][ T9784] ? __mark_inode_dirty+0x29e/0xe40 [ 174.854483][ T9784] hfsplus_delete_cat+0x845/0xde0 [ 174.854493][ T9784] ? __pfx_hfsplus_delete_cat+0x10/0x10 [ 174.854507][ T9784] hfsplus_unlink+0x1ca/0x7c0 [ 174.854516][ T9784] ? __pfx_hfsplus_unlink+0x10/0x10 [ 174.854525][ T9784] ? down_write+0x148/0x200 [ 174.854532][ T9784] ? __pfx_down_write+0x10/0x10 [ 174.854540][ T9784] vfs_unlink+0x2fe/0x9b0 [ 174.854549][ T9784] do_unlinkat+0x490/0x670 [ 174.854557][ T9784] ? __pfx_do_unlinkat+0x10/0x10 [ 174.854565][ T9784] ? __might_fault+0xbc/0x130 [ 174.854576][ T9784] ? getname_flags.part.0+0x1c5/0x550 [ 174.854584][ T9784] __x64_sys_unlink+0xc5/0x110 [ 174.854592][ T9784] do_syscall_64+0xc9/0x480 [ 174.854600][ T9784] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 174.854608][ T9784] RIP: 0033:0x7f6fdf4c3167 [ 174.854614][ T9784] Code: f0 ff ff 73 01 c3 48 8b 0d 26 0d 0e 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 08 [ 174.854622][ T9784] RSP: 002b:00007ffcb948bca8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 [ 174.854630][ T9784] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6fdf4c3167 [ 174.854636][ T9784] RDX: 00007ffcb948bcc0 RSI: 00007ffcb948bcc0 RDI: 00007ffcb948bd50 [ 174.854641][ T9784] RBP: 00007ffcb948cd90 R08: 0000000000000001 R09: 00007ffcb948bb40 [ 174.854645][ T9784] R10: 00007f6fdf564fc0 R11: 0000000000000206 R12: 0000561e1bc9c2d0 [ 174.854650][ T9784] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 174.854658][ T9784] [ 174.854661][ T9784] [ 174.879281][ T9784] Allocated by task 9784: [ 174.879664][ T9784] kasan_save_stack+0x20/0x40 [ 174.880082][ T9784] kasan_save_track+0x14/0x30 [ 174.880500][ T9784] __kasan_kmalloc+0xaa/0xb0 [ 174.880908][ T9784] __kmalloc_noprof+0x205/0x550 [ 174.881337][ T9784] __hfs_bnode_create+0x107/0x890 [ 174.881779][ T9784] hfsplus_bnode_find+0x2d0/0xd10 [ 174.882222][ T9784] hfsplus_brec_find+0x2b0/0x520 [ 174.882659][ T9784] hfsplus_delete_all_attrs+0x23b/0x3 —truncated—

Weakness

The product reads data past the end, or before the beginning, of the intended buffer.

Affected Software

Potential Mitigations

• Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
• When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
• Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
• To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/540.html

References

• https://git.kernel.org/stable/c/032f7ed6717a4cd3714f9801be39fdfc7f1c7644
• https://git.kernel.org/stable/c/291b7f2538920aa229500dbdd6c5f0927a51bc8b
• https://git.kernel.org/stable/c/475d770c19929082aab43337e6c077d0e2043df3
• https://git.kernel.org/stable/c/5ab59229bef6063edf3a6fc2e3e3fd7cd2181b29
• https://git.kernel.org/stable/c/7fa4cef8ea13b37811287ef60674c5fd1dd02ee6
• https://git.kernel.org/stable/c/8583d067ae22b7f32ce5277ca5543ac8bf86a3e5
• https://git.kernel.org/stable/c/a2abd574d2fe22b8464cf6df5abb6f24d809eac0
• https://git.kernel.org/stable/c/c80aa2aaaa5e69d5219c6af8ef7e754114bd08d2
• https://git.kernel.org/stable/c/ffee8a7bed0fbfe29da239a922b59c5db897c613
• https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
• https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html