Linux kernel source tree
Go to file
Viacheslav Dubeyko 736a0516a1 hfs: fix general protection fault in hfs_find_init()
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]  do_syscall_64+0xc9/0x480
[   45.781631][ T9787]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[   45.782149][ T9787] RIP: 0033:0x7ffb7265b6ca
[   45.782539][ T9787] Code: 48 8b 0d c9 17 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48
[   45.784212][ T9787] RSP: 002b:00007ffc0c10cfb8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
[   45.784935][ T9787] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffb7265b6ca
[   45.785626][ T9787] RDX: 0000200000000240 RSI: 0000200000000280 RDI: 00007ffc0c10d100
[   45.786316][ T9787] RBP: 00007ffc0c10d190 R08: 00007ffc0c10d000 R09: 0000000000000000
[   45.787011][ T9787] R10: 0000000000000048 R11: 0000000000000206 R12: 0000560246733250
[   45.787697][ T9787] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[   45.788393][ T9787]  </TASK>
[   45.788665][ T9787] Modules linked in:
[   45.789058][ T9787] ---[ end trace 0000000000000000 ]---
[   45.789554][ T9787] RIP: 0010:hfs_find_init+0x86/0x230
[   45.790028][ 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
[   45.792364][ T9787] RSP: 0018:ffffc90015157668 EFLAGS: 00010202
[   45.793155][ T9787] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff819a4d09
[   45.794123][ T9787] RDX: 0000000000000008 RSI: ffffffff819acd3a RDI: ffffc900151576e8
[   45.795105][ T9787] RBP: ffffc900151576d0 R08: 0000000000000005 R09: 0000000000000000
[   45.796135][ T9787] R10: 0000000080000000 R11: 0000000000000001 R12: 0000000000000004
[   45.797114][ T9787] R13: 0000000000000040 R14: ffff88802c50814a R15: 0000000000000000
[   45.798024][ T9787] FS:  00007ffb72734540(0000) GS:ffff8880cec64000(0000) knlGS:0000000000000000
[   45.799019][ T9787] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   45.799822][ T9787] CR2: 00007f9bd8225000 CR3: 000000010979a000 CR4: 00000000000006f0
[   45.800747][ T9787] Kernel panic - not syncing: Fatal exception

The hfs_fill_super() calls hfs_mdb_get() method that tries
to construct Extents Tree and Catalog Tree:

HFS_SB(sb)->ext_tree = hfs_btree_open(sb, HFS_EXT_CNID, hfs_ext_keycmp);
if (!HFS_SB(sb)->ext_tree) {
	pr_err("unable to open extent tree\n");
	goto out;
}
HFS_SB(sb)->cat_tree = hfs_btree_open(sb, HFS_CAT_CNID, hfs_cat_keycmp);
if (!HFS_SB(sb)->cat_tree) {
	pr_err("unable to open catalog tree\n");
	goto out;
}

However, hfs_btree_open() calls read_mapping_page() that
calls hfs_get_block(). And this method calls hfs_ext_read_extent():

static int hfs_ext_read_extent(struct inode *inode, u16 block)
{
	struct hfs_find_data fd;
	int res;

	if (block >= HFS_I(inode)->cached_start &&
	    block < HFS_I(inode)->cached_start + HFS_I(inode)->cached_blocks)
		return 0;

	res = hfs_find_init(HFS_SB(inode->i_sb)->ext_tree, &fd);
	if (!res) {
		res = __hfs_ext_cache_extent(&fd, inode, block);
		hfs_find_exit(&fd);
	}
	return res;
}

The problem here that hfs_find_init() is trying to use
HFS_SB(inode->i_sb)->ext_tree that is not initialized yet.
It will be initailized when hfs_btree_open() finishes
the execution.

The patch adds checking of tree pointer in hfs_find_init()
and it reworks the logic of hfs_btree_open() by reading
the b-tree's header directly from the volume. The read_mapping_page()
is exchanged on filemap_grab_folio() that grab the folio from
mapping. Then, sb_bread() extracts the b-tree's header
content and copy it into the folio.

Reported-by: Wenzhi Wang <wenzhi.wang@uwaterloo.ca>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
cc: Yangtao Li <frank.li@vivo.com>
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20250710213657.108285-1-slava@dubeyko.com
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
2025-07-25 15:40:16 -07:00
arch The delayed from_timer() API cleanup: 2025-06-08 11:33:00 -07:00
block treewide, timers: Rename from_timer() to timer_container_of() 2025-06-08 09:07:37 +02:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto EFI updates for v6.16 2025-05-30 12:42:57 -07:00
Documentation fourteen smb3 client fixes, most smbdirect related 2025-06-08 10:20:21 -07:00
drivers The delayed from_timer() API cleanup: 2025-06-08 11:33:00 -07:00
fs hfs: fix general protection fault in hfs_find_init() 2025-07-25 15:40:16 -07:00
include The delayed from_timer() API cleanup: 2025-06-08 11:33:00 -07:00
init Rust changes for v6.16 2025-06-04 21:18:37 -07:00
io_uring io_uring-6.16-20250606 2025-06-06 13:09:03 -07:00
ipc - The 3 patch series "hung_task: extend blocking task stacktrace dump to 2025-05-31 19:12:53 -07:00
kernel The delayed from_timer() API cleanup: 2025-06-08 11:33:00 -07:00
lib 13 hotfixes. 6 are cc:stable and the remainder address post-6.15 issues 2025-06-06 21:45:45 -07:00
LICENSES LICENSES: add CC0-1.0 license text 2025-05-21 14:54:17 +02:00
mm treewide, timers: Rename from_timer() to timer_container_of() 2025-06-08 09:07:37 +02:00
net treewide, timers: Rename from_timer() to timer_container_of() 2025-06-08 09:07:37 +02:00
rust Char/Misc/IIO pull request for 6.16-rc1 2025-06-06 11:50:47 -07:00
samples - The 3 patch series "hung_task: extend blocking task stacktrace dump to 2025-05-31 19:12:53 -07:00
scripts Kbuild updates for v6.16 2025-06-07 10:05:35 -07:00
security require gcc-8 and binutils-2.30 2025-05-31 08:16:52 -07:00
sound treewide, timers: Rename from_timer() to timer_container_of() 2025-06-08 09:07:37 +02:00
tools turbostat v2025.06.08 2025-06-08 11:44:41 -07:00
usr usr/include: openrisc: don't HDRTEST bpf_perf_event.h 2025-05-12 15:03:17 +09:00
virt Merge branch 'kvm-lockdep-common' into HEAD 2025-05-28 06:29:17 -04:00
.clang-format Linux 6.15-rc5 2025-05-06 16:39:25 +10:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: ignore Python compiled bytecode 2025-04-24 10:12:46 -06:00
.mailmap fourteen smb3 client fixes, most smbdirect related 2025-06-08 10:20:21 -07:00
.pylintrc docs: add a .pylintrc file with sys path for docs scripts 2025-04-09 12:10:33 -06:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS Update Christoph's Email address and make it consistent 2025-05-12 23:50:31 -07:00
Kbuild drm: ensure drm headers are self-contained and pass kernel-doc 2025-02-12 10:44:43 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS fourteen smb3 client fixes, most smbdirect related 2025-06-08 10:20:21 -07:00
Makefile Linux 6.16-rc1 2025-06-08 13:44:43 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.