{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-46299","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-05-13T15:03:33.111Z","datePublished":"2026-06-08T15:46:26.670Z","dateUpdated":"2026-08-05T12:31:04.308Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:31:04.308Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nhfsplus: fix held lock freed on hfsplus_fill_super()\n\nhfsplus_fill_super() calls hfs_find_init() to initialize a search\nstructure, which acquires tree->tree_lock. If the subsequent call to\nhfsplus_cat_build_key() fails, the function jumps to the out_put_root\nerror label without releasing the lock. The later cleanup path then\nfrees the tree data structure with the lock still held, triggering a\nheld lock freed warning.\n\nFix this by adding the missing hfs_find_exit(&fd) call before jumping\nto the out_put_root error label. This ensures that tree->tree_lock is\nproperly released on the error path.\n\nThe bug was originally detected on v6.13-rc1 using an experimental\nstatic analysis tool we are developing, and we have verified that the\nissue persists in the latest mainline kernel. The tool is specifically\ndesigned to detect memory management issues. It is currently under active\ndevelopment and not yet publicly available.\n\nWe confirmed the bug by runtime testing under QEMU with x86_64 defconfig,\nlockdep enabled, and CONFIG_HFSPLUS_FS=y. To trigger the error path, we\nused GDB to dynamically shrink the max_unistr_len parameter to 1 before\nhfsplus_asc2uni() is called. This forces hfsplus_asc2uni() to naturally\nreturn -ENAMETOOLONG, which propagates to hfsplus_cat_build_key() and\nexercises the faulty error path. The following warning was observed\nduring mount:\n\n\t=========================\n\tWARNING: held lock freed!\n\t7.0.0-rc3-00016-gb4f0dd314b39 #4 Not tainted\n\t-------------------------\n\tmount/174 is freeing memory ffff888103f92000-ffff888103f92fff, with a lock still held there!\n\tffff888103f920b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x154/0x1e0\n\t2 locks held by mount/174:\n\t#0: ffff888103f960e0 (&type->s_umount_key#42/1){+.+.}-{4:4}, at: alloc_super.constprop.0+0x167/0xa40\n\t#1: ffff888103f920b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x154/0x1e0\n\n\tstack backtrace:\n\tCPU: 2 UID: 0 PID: 174 Comm: mount Not tainted 7.0.0-rc3-00016-gb4f0dd314b39 #4 PREEMPT(lazy)\n\tHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014\n\tCall Trace:\n\t<TASK>\n\tdump_stack_lvl+0x82/0xd0\n\tdebug_check_no_locks_freed+0x13a/0x180\n\tkfree+0x16b/0x510\n\t? hfsplus_fill_super+0xcb4/0x18a0\n\thfsplus_fill_super+0xcb4/0x18a0\n\t? __pfx_hfsplus_fill_super+0x10/0x10\n\t? srso_return_thunk+0x5/0x5f\n\t? bdev_open+0x65f/0xc30\n\t? srso_return_thunk+0x5/0x5f\n\t? pointer+0x4ce/0xbf0\n\t? trace_contention_end+0x11c/0x150\n\t? __pfx_pointer+0x10/0x10\n\t? srso_return_thunk+0x5/0x5f\n\t? bdev_open+0x79b/0xc30\n\t? srso_return_thunk+0x5/0x5f\n\t? srso_return_thunk+0x5/0x5f\n\t? vsnprintf+0x6da/0x1270\n\t? srso_return_thunk+0x5/0x5f\n\t? __mutex_unlock_slowpath+0x157/0x740\n\t? __pfx_vsnprintf+0x10/0x10\n\t? srso_return_thunk+0x5/0x5f\n\t? srso_return_thunk+0x5/0x5f\n\t? mark_held_locks+0x49/0x80\n\t? srso_return_thunk+0x5/0x5f\n\t? srso_return_thunk+0x5/0x5f\n\t? irqentry_exit+0x17b/0x5e0\n\t? trace_irq_disable.constprop.0+0x116/0x150\n\t? __pfx_hfsplus_fill_super+0x10/0x10\n\t? __pfx_hfsplus_fill_super+0x10/0x10\n\tget_tree_bdev_flags+0x302/0x580\n\t? __pfx_get_tree_bdev_flags+0x10/0x10\n\t? vfs_parse_fs_qstr+0x129/0x1a0\n\t? __pfx_vfs_parse_fs_qstr+0x3/0x10\n\tvfs_get_tree+0x89/0x320\n\tfc_mount+0x10/0x1d0\n\tpath_mount+0x5c5/0x21c0\n\t? __pfx_path_mount+0x10/0x10\n\t? trace_irq_enable.constprop.0+0x116/0x150\n\t? trace_irq_enable.constprop.0+0x116/0x150\n\t? srso_return_thunk+0x5/0x5f\n\t? srso_return_thunk+0x5/0x5f\n\t? kmem_cache_free+0x307/0x540\n\t? user_path_at+0x51/0x60\n\t? __x64_sys_mount+0x212/0x280\n\t? srso_return_thunk+0x5/0x5f\n\t__x64_sys_mount+0x212/0x280\n\t? __pfx___x64_sys_mount+0x10/0x10\n\t? srso_return_thunk+0x5/0x5f\n\t? trace_irq_enable.constprop.0+0x116/0x150\n\t? srso_return_thunk+0x5/0x5f\n\tdo_syscall_64+0x111/0x680\n\tentry_SYSCALL_64_after_hwframe+0x77/0x7f\n\tRIP: 0033:0x7ffacad55eae\n\tCode: 48 8b 0d 85 1f 0f 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 8\n\tRSP: 002b\n---truncated---"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The bug is only reachable through the local mount syscall path (__x64_sys_mount → path_mount → vfs_get_tree → get_tree_bdev → hfsplus_fill_super); hfsplus is a block-device filesystem with no network-facing handler.\nAC:H - The faulty branch requires hfsplus_cat_build_key() to fail on the hardcoded HFSP_HIDDENDIR_NAME string (29 bytes, limit 255), which researchers could only trigger by GDB-patching max_unistr_len; attackers cannot influence this input via a crafted HFS+ image.\nPR:L - Exploitation requires mounting an hfsplus volume, which needs CAP_SYS_ADMIN; per kernel CNA guidance this is Low because unprivileged users with user-namespace CAP_SYS_ADMIN can mount loop-backed filesystems.\nUI:N - No victim interaction is required; the attacker (or their user-namespace root) initiates the mount syscall directly to reach the vulnerable cleanup path.\nS:U - Impact is confined to kernel memory/locking state during mount teardown; it does not cross a VM, container, or IOMMU security boundary.\nC:H - Freeing the hfs_btree structure while tree_lock is still held corrupts lock lifecycle state and can lead to use-after-free of the embedded mutex metadata when the slab is reused, enabling potential kernel memory disclosure.\nI:H - The held-lock-during-kfree condition is a memory-management corruption bug that can corrupt mutex/lockdep state and potentially be leveraged for further kernel memory writes or control-flow disruption.\nA:H - The confirmed runtime impact is a lockdep \"held lock freed\" warning during mount failure, and freeing kernel structures with active locks can cause kernel instability, oops, or panic on subsequent lock operations."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/hfsplus/super.c"],"versions":[{"version":"89ac9b4d3d1a049ae1054f99b1aed81092cd0a82","lessThan":"e890656accee4c26d932ea388eb8936a6e22184d","status":"affected","versionType":"git"},{"version":"89ac9b4d3d1a049ae1054f99b1aed81092cd0a82","lessThan":"6499c9c8ec437a369e7e221dad91f6122b50759d","status":"affected","versionType":"git"},{"version":"89ac9b4d3d1a049ae1054f99b1aed81092cd0a82","lessThan":"c554ddc87af4d4e4be42f8aed1baec9e1c7588e0","status":"affected","versionType":"git"},{"version":"89ac9b4d3d1a049ae1054f99b1aed81092cd0a82","lessThan":"3ca80e3012c8be85b4f8d0d20eac8d3b17ff257e","status":"affected","versionType":"git"},{"version":"89ac9b4d3d1a049ae1054f99b1aed81092cd0a82","lessThan":"041acda6d9f96006703466449c10c9a69590c8b9","status":"affected","versionType":"git"},{"version":"89ac9b4d3d1a049ae1054f99b1aed81092cd0a82","lessThan":"d309d3308de658d87c42d97e044c89a226327526","status":"affected","versionType":"git"},{"version":"89ac9b4d3d1a049ae1054f99b1aed81092cd0a82","lessThan":"bfbcce6a7b0552a390620d9b2c4d2bcb1825cbdc","status":"affected","versionType":"git"},{"version":"89ac9b4d3d1a049ae1054f99b1aed81092cd0a82","lessThan":"90c500e4fd83fa33c09bc7ee23b6d9cc487ac733","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/hfsplus/super.c"],"versions":[{"version":"3.19","status":"affected"},{"version":"0","lessThan":"3.19","status":"unaffected","versionType":"semver"},{"version":"5.10.259","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.210","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.176","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.140","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.88","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.30","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.7","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.19","versionEndExcluding":"5.10.259"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.19","versionEndExcluding":"5.15.210"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.19","versionEndExcluding":"6.1.176"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.19","versionEndExcluding":"6.6.140"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.19","versionEndExcluding":"6.12.88"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.19","versionEndExcluding":"6.18.30"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.19","versionEndExcluding":"7.0.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.19","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/e890656accee4c26d932ea388eb8936a6e22184d"},{"url":"https://git.kernel.org/stable/c/6499c9c8ec437a369e7e221dad91f6122b50759d"},{"url":"https://git.kernel.org/stable/c/c554ddc87af4d4e4be42f8aed1baec9e1c7588e0"},{"url":"https://git.kernel.org/stable/c/3ca80e3012c8be85b4f8d0d20eac8d3b17ff257e"},{"url":"https://git.kernel.org/stable/c/041acda6d9f96006703466449c10c9a69590c8b9"},{"url":"https://git.kernel.org/stable/c/d309d3308de658d87c42d97e044c89a226327526"},{"url":"https://git.kernel.org/stable/c/bfbcce6a7b0552a390620d9b2c4d2bcb1825cbdc"},{"url":"https://git.kernel.org/stable/c/90c500e4fd83fa33c09bc7ee23b6d9cc487ac733"}],"title":"hfsplus: fix held lock freed on hfsplus_fill_super()","x_generator":{"engine":"bippy-1.2.0"}}}}