CVE-2024-46782

Published Sep 18, 2024

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ila: call nf_unregister_net_hooks() sooner syzbot found an use-after-free Read in ila_nf_input [1] Issue here is that ila_xlat_exit_net() frees the rhashtable, then call nf_unregister_net_hooks(). It should be done in the reverse way, with a synchronize_rcu(). This is a good match for a pre_exit() method. [1] BUG: KASAN: use-after-free in rht_key_hashfn include/linux/rhashtable.h:159 [inline] BUG: KASAN: use-after-free in __rhashtable_lookup include/linux/rhashtable.h:604 [inline] BUG: KASAN: use-after-free in rhashtable_lookup include/linux/rhashtable.h:646 [inline] BUG: KASAN: use-after-free in rhashtable_lookup_fast+0x77a/0x9b0 include/linux/rhashtable.h:672 Read of size 4 at addr ffff888064620008 by task ksoftirqd/0/16 CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.11.0-rc4-syzkaller-00238-g2ad6d23f465a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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 rht_key_hashfn include/linux/rhashtable.h:159 [inline] __rhashtable_lookup include/linux/rhashtable.h:604 [inline] rhashtable_lookup include/linux/rhashtable.h:646 [inline] rhashtable_lookup_fast+0x77a/0x9b0 include/linux/rhashtable.h:672 ila_lookup_wildcards net/ipv6/ila/ila_xlat.c:132 [inline] ila_xlat_addr net/ipv6/ila/ila_xlat.c:652 [inline] ila_nf_input+0x1fe/0x3c0 net/ipv6/ila/ila_xlat.c:190 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 __netif_receive_skb_one_core net/core/dev.c:5661 [inline] __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6108 __napi_poll+0xcb/0x490 net/core/dev.c:6772 napi_poll net/core/dev.c:6841 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6963 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:928 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x64620 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xbfffffff(buddy) raw: 00fff00000000000 ffffea0000959608 ffffea00019d9408 0000000000000000 raw: 0000000000000000 0000000000000003 00000000bfffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 3, migratetype Unmovable, gfp_mask 0x52dc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_ZERO), pid 5242, tgid 5242 (syz-executor), ts 73611328570, free_ts 618981657187 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493 prep_new_page mm/page_alloc.c:1501 [inline] get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3439 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] ___kmalloc_large_node+0x8b/0x1d0 mm/slub.c:4103 __kmalloc_large_node_noprof+0x1a/0x80 mm/slub.c:4130 __do_kmalloc_node mm/slub.c:4146 [inline] __kmalloc_node_noprof+0x2d2/0x440 mm/slub.c:4164 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:650 bucket_table_alloc lib/rhashtable.c:186 [inline] rhashtable_init_noprof+0x534/0xa60 lib/rhashtable.c:1071 ila_xlat_init_net+0xa0/0x110 net/ipv6/ila/ila_xlat.c:613 ops_ini ---truncated---
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-416

Social media

Hype score
Not currently trending

Configurations

  1. In the Linux kernel, the following vulnerability has been resolved: coresight: tmc-etr: Fix race condition between sysfs and perf mode When trying to run perf and sysfs mode simultaneously, the WARN_ON() in tmc_etr_enable_hw() is triggered sometimes: WARNING: CPU: 42 PID: 3911571 at drivers/hwtracing/coresight/coresight-tmc-etr.c:1060 tmc_etr_enable_hw+0xc0/0xd8 [coresight_tmc] [..snip..] Call trace: tmc_etr_enable_hw+0xc0/0xd8 [coresight_tmc] (P) tmc_enable_etr_sink+0x11c/0x250 [coresight_tmc] (L) tmc_enable_etr_sink+0x11c/0x250 [coresight_tmc] coresight_enable_path+0x1c8/0x218 [coresight] coresight_enable_sysfs+0xa4/0x228 [coresight] enable_source_store+0x58/0xa8 [coresight] dev_attr_store+0x20/0x40 sysfs_kf_write+0x4c/0x68 kernfs_fop_write_iter+0x120/0x1b8 vfs_write+0x2c8/0x388 ksys_write+0x74/0x108 __arm64_sys_write+0x24/0x38 el0_svc_common.constprop.0+0x64/0x148 do_el0_svc+0x24/0x38 el0_svc+0x3c/0x130 el0t_64_sync_handler+0xc8/0xd0 el0t_64_sync+0x1ac/0x1b0 ---[ end trace 0000000000000000 ]--- Since the enablement of sysfs mode is separeted into two critical regions, one for sysfs buffer allocation and another for hardware enablement, it's possible to race with the perf mode. Fix this by double check whether the perf mode's been used before enabling the hardware in sysfs mode. mode: [sysfs mode] [perf mode] tmc_etr_get_sysfs_buffer() spin_lock(&drvdata->spinlock) [sysfs buffer allocation] spin_unlock(&drvdata->spinlock) spin_lock(&drvdata->spinlock) tmc_etr_enable_hw() drvdata->etr_buf = etr_perf->etr_buf spin_unlock(&drvdata->spinlock) spin_lock(&drvdata->spinlock) tmc_etr_enable_hw() WARN_ON(drvdata->etr_buf) // WARN sicne etr_buf initialized at the perf side spin_unlock(&drvdata->spinlock) With this fix, we retain the check for CS_MODE_PERF in get_etr_sysfs_buf. This ensures we verify whether the perf mode's already running before we actually allocate the buffer. Then we can save the time of allocating/freeing the sysfs buffer if race with the perf mode.CVE-2026-46272