Description

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Return error for inconsistent extended attributes ntfs_read_ea is called when we want to read extended attributes. There are some sanity checks for the validity of the EAs. However, it fails to return a proper error code for the inconsistent attributes, which might lead to unpredicted memory accesses after return. [ 138.916927] BUG: KASAN: use-after-free in ntfs_set_ea+0x453/0xbf0 [ 138.923876] Write of size 4 at addr ffff88800205cfac by task poc/199 [ 138.931132] [ 138.933016] CPU: 0 PID: 199 Comm: poc Not tainted 6.2.0-rc1+ #4 [ 138.938070] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 [ 138.947327] Call Trace: [ 138.949557] <TASK> [ 138.951539] dump_stack_lvl+0x4d/0x67 [ 138.956834] print_report+0x16f/0x4a6 [ 138.960798] ? ntfs_set_ea+0x453/0xbf0 [ 138.964437] ? kasan_complete_mode_report_info+0x7d/0x200 [ 138.969793] ? ntfs_set_ea+0x453/0xbf0 [ 138.973523] kasan_report+0xb8/0x140 [ 138.976740] ? ntfs_set_ea+0x453/0xbf0 [ 138.980578] __asan_store4+0x76/0xa0 [ 138.984669] ntfs_set_ea+0x453/0xbf0 [ 138.988115] ? __pfx_ntfs_set_ea+0x10/0x10 [ 138.993390] ? kernel_text_address+0xd3/0xe0 [ 138.998270] ? __kernel_text_address+0x16/0x50 [ 139.002121] ? unwind_get_return_address+0x3e/0x60 [ 139.005659] ? __pfx_stack_trace_consume_entry+0x10/0x10 [ 139.010177] ? arch_stack_walk+0xa2/0x100 [ 139.013657] ? filter_irq_stacks+0x27/0x80 [ 139.017018] ntfs_setxattr+0x405/0x440 [ 139.022151] ? __pfx_ntfs_setxattr+0x10/0x10 [ 139.026569] ? kvmalloc_node+0x2d/0x120 [ 139.030329] ? kasan_save_stack+0x41/0x60 [ 139.033883] ? kasan_save_stack+0x2a/0x60 [ 139.037338] ? kasan_set_track+0x29/0x40 [ 139.040163] ? kasan_save_alloc_info+0x1f/0x30 [ 139.043588] ? __kasan_kmalloc+0x8b/0xa0 [ 139.047255] ? __kmalloc_node+0x68/0x150 [ 139.051264] ? kvmalloc_node+0x2d/0x120 [ 139.055301] ? vmemdup_user+0x2b/0xa0 [ 139.058584] __vfs_setxattr+0x121/0x170 [ 139.062617] ? __pfx___vfs_setxattr+0x10/0x10 [ 139.066282] __vfs_setxattr_noperm+0x97/0x300 [ 139.070061] __vfs_setxattr_locked+0x145/0x170 [ 139.073580] vfs_setxattr+0x137/0x2a0 [ 139.076641] ? __pfx_vfs_setxattr+0x10/0x10 [ 139.080223] ? __kasan_check_write+0x18/0x20 [ 139.084234] do_setxattr+0xce/0x150 [ 139.087768] setxattr+0x126/0x140 [ 139.091250] ? __pfx_setxattr+0x10/0x10 [ 139.094948] ? __virt_addr_valid+0xcb/0x140 [ 139.097838] ? __call_rcu_common.constprop.0+0x1c7/0x330 [ 139.102688] ? debug_smp_processor_id+0x1b/0x30 [ 139.105985] ? kasan_quarantine_put+0x5b/0x190 [ 139.109980] ? putname+0x84/0xa0 [ 139.113886] ? __kasan_slab_free+0x11e/0x1b0 [ 139.117961] ? putname+0x84/0xa0 [ 139.121316] ? preempt_count_sub+0x1c/0xd0 [ 139.124427] ? __mnt_want_write+0xae/0x100 [ 139.127836] ? mnt_want_write+0x8f/0x150 [ 139.130954] path_setxattr+0x164/0x180 [ 139.133998] ? __pfx_path_setxattr+0x10/0x10 [ 139.137853] ? __pfx_ksys_pwrite64+0x10/0x10 [ 139.141299] ? debug_smp_processor_id+0x1b/0x30 [ 139.145714] ? fpregs_assert_state_consistent+0x6b/0x80 [ 139.150796] __x64_sys_setxattr+0x71/0x90 [ 139.155407] do_syscall_64+0x3f/0x90 [ 139.159035] entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 139.163843] RIP: 0033:0x7f108cae4469 [ 139.166481] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 088 [ 139.183764] RSP: 002b:00007fff87588388 EFLAGS: 00000286 ORIG_RAX: 00000000000000bc [ 139.190657] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f108cae4469 [ 139.196586] RDX: 00007fff875883b0 RSI: 00007fff875883d1 RDI: 00007fff875883b6 [ 139.201716] RBP: 00007fff8758c530 R08: 0000000000000001 R09: 00007fff8758c618 [ 139.207940] R10: 0000000000000006 R11: 0000000000000286 R12: 00000000004004c0 [ 139.214007] R13: 00007fff8758c610 R14: 0000000000000000 R15 ---truncated---

References 4

• git.kernel.org https://git.kernel.org/stable/c/1474098b590a426d90f27bb992f17c326e0b60c1
• git.kernel.org https://git.kernel.org/stable/c/486666c2c2714788705d02d98d0332c8a2328575
• git.kernel.org https://git.kernel.org/stable/c/6557c4504c5a1bbbbac25d14d7dcf2a4912d1508
• git.kernel.org https://git.kernel.org/stable/c/c9db0ff04649aa0b45f497183c957fe260f229f6

Remediation