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Larshin Sergey 918649364f fs: udf: fix OOB read in lengthAllocDescs handling
commit 3bd5e45c2ce30e239d596becd5db720f7eb83c99 upstream.

When parsing Allocation Extent Descriptor, lengthAllocDescs comes from
on-disk data and must be validated against the block size. Crafted or
corrupted images may set lengthAllocDescs so that the total descriptor
length (sizeof(allocExtDesc) + lengthAllocDescs) exceeds the buffer,
leading udf_update_tag() to call crc_itu_t() on out-of-bounds memory and
trigger a KASAN use-after-free read.

BUG: KASAN: use-after-free in crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60
Read of size 1 at addr ffff888041e7d000 by task syz-executor317/5309

CPU: 0 UID: 0 PID: 5309 Comm: syz-executor317 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60
 udf_update_tag+0x70/0x6a0 fs/udf/misc.c:261
 udf_write_aext+0x4d8/0x7b0 fs/udf/inode.c:2179
 extent_trunc+0x2f7/0x4a0 fs/udf/truncate.c:46
 udf_truncate_tail_extent+0x527/0x7e0 fs/udf/truncate.c:106
 udf_release_file+0xc1/0x120 fs/udf/file.c:185
 __fput+0x23f/0x880 fs/file_table.c:431
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:939
 do_group_exit+0x207/0x2c0 kernel/exit.c:1088
 __do_sys_exit_group kernel/exit.c:1099 [inline]
 __se_sys_exit_group kernel/exit.c:1097 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097
 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
 </TASK>

Validate the computed total length against epos->bh->b_size.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Reported-by: syzbot+8743fca924afed42f93e@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=8743fca924afed42f93e
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Larshin Sergey <Sergey.Larshin@kaspersky.com>
Link: https://patch.msgid.link/20250922131358.745579-1-Sergey.Larshin@kaspersky.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 11:56:39 +02:00
arch sparc: fix accurate exception reporting in copy_{from,to}_user for M7 2025-10-15 11:56:36 +02:00
block block: use int to store blk_stack_limits() return value 2025-10-15 11:56:27 +02:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2025-04-25 10:44:04 +02:00
crypto crypto: rng - Ensure set_ent is always present 2025-10-15 11:56:24 +02:00
Documentation Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram 2025-10-15 11:56:35 +02:00
drivers uio_hv_generic: Let userspace take care of interrupt mask 2025-10-15 11:56:39 +02:00
fs fs: udf: fix OOB read in lengthAllocDescs handling 2025-10-15 11:56:39 +02:00
include bpf: Enforce expected_attach_type for tailcall compatibility 2025-10-15 11:56:29 +02:00
init init: INITRAMFS_PRESERVE_MTIME should depend on BLK_DEV_INITRD 2025-10-15 11:56:25 +02:00
io_uring io_uring: include dying ring in task_work "should cancel" state 2025-09-25 10:58:53 +02:00
ipc ipc: fix to protect IPCS lookups using RCU 2025-06-27 11:07:30 +01:00
kernel bpf: Enforce expected_attach_type for tailcall compatibility 2025-10-15 11:56:29 +02:00
lib minmax: don't use max() in situations that want a C constant expression 2025-10-15 11:56:21 +02:00
LICENSES
mm minmax: make generic MIN() and MAX() macros available everywhere 2025-10-02 13:40:43 +02:00
net Bluetooth: hci_sync: Fix using random address for BIG/PA advertisements 2025-10-15 11:56:37 +02:00
rust rust: module: place cleanup_module() in .exit.text section 2025-07-06 10:57:54 +02:00
samples ftrace/samples: Fix function size computation 2025-09-19 16:29:56 +02:00
scripts gcc-plugins: Remove TODO_verify_il for GCC >= 16 2025-10-15 11:56:20 +02:00
security apparmor: use the condition in AA_BUG_FMT even with debug disabled 2025-08-28 16:26:01 +02:00
sound ASoC: Intel: bytcr_rt5651: Fix invalid quirk input mapping 2025-10-15 11:56:33 +02:00
tools tools/nolibc: make time_t robust if __kernel_old_time_t is missing in host headers 2025-10-15 11:56:29 +02:00
usr kbuild: hdrcheck: fix cross build with clang 2025-06-27 11:07:25 +01:00
virt KVM: Fix a data race on last_boosted_vcpu in kvm_vcpu_on_spin() 2024-06-27 13:46:21 +02:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore Remove *.orig pattern from .gitignore 2024-10-17 15:21:15 +02:00
.mailmap
.rustfmt.toml
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS sign-file,extract-cert: move common SSL helper functions to a header 2025-04-25 10:44:04 +02:00
Makefile Linux 6.1.155 2025-10-02 13:40:43 +02:00
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