CVE-2024-49932

Published Oct 21, 2024

Last updated 2 years ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: btrfs: don't readahead the relocation inode on RST On relocation we're doing readahead on the relocation inode, but if the filesystem is backed by a RAID stripe tree we can get ENOENT (e.g. due to preallocated extents not being mapped in the RST) from the lookup. But readahead doesn't handle the error and submits invalid reads to the device, causing an assertion in the scatter-gather list code: BTRFS info (device nvme1n1): balance: start -d -m -s BTRFS info (device nvme1n1): relocating block group 6480920576 flags data|raid0 BTRFS error (device nvme1n1): cannot find raid-stripe for logical [6481928192, 6481969152] devid 2, profile raid0 ------------[ cut here ]------------ kernel BUG at include/linux/scatterlist.h:115! Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 1012 Comm: btrfs Not tainted 6.10.0-rc7+ #567 RIP: 0010:__blk_rq_map_sg+0x339/0x4a0 RSP: 0018:ffffc90001a43820 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffea00045d4802 RDX: 0000000117520000 RSI: 0000000000000000 RDI: ffff8881027d1000 RBP: 0000000000003000 R08: ffffea00045d4902 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000001000 R12: ffff8881003d10b8 R13: ffffc90001a438f0 R14: 0000000000000000 R15: 0000000000003000 FS: 00007fcc048a6900(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002cd11000 CR3: 00000001109ea001 CR4: 0000000000370eb0 Call Trace: <TASK> ? __die_body.cold+0x14/0x25 ? die+0x2e/0x50 ? do_trap+0xca/0x110 ? do_error_trap+0x65/0x80 ? __blk_rq_map_sg+0x339/0x4a0 ? exc_invalid_op+0x50/0x70 ? __blk_rq_map_sg+0x339/0x4a0 ? asm_exc_invalid_op+0x1a/0x20 ? __blk_rq_map_sg+0x339/0x4a0 nvme_prep_rq.part.0+0x9d/0x770 nvme_queue_rq+0x7d/0x1e0 __blk_mq_issue_directly+0x2a/0x90 ? blk_mq_get_budget_and_tag+0x61/0x90 blk_mq_try_issue_list_directly+0x56/0xf0 blk_mq_flush_plug_list.part.0+0x52b/0x5d0 __blk_flush_plug+0xc6/0x110 blk_finish_plug+0x28/0x40 read_pages+0x160/0x1c0 page_cache_ra_unbounded+0x109/0x180 relocate_file_extent_cluster+0x611/0x6a0 ? btrfs_search_slot+0xba4/0xd20 ? balance_dirty_pages_ratelimited_flags+0x26/0xb00 relocate_data_extent.constprop.0+0x134/0x160 relocate_block_group+0x3f2/0x500 btrfs_relocate_block_group+0x250/0x430 btrfs_relocate_chunk+0x3f/0x130 btrfs_balance+0x71b/0xef0 ? kmalloc_trace_noprof+0x13b/0x280 btrfs_ioctl+0x2c2e/0x3030 ? kvfree_call_rcu+0x1e6/0x340 ? list_lru_add_obj+0x66/0x80 ? mntput_no_expire+0x3a/0x220 __x64_sys_ioctl+0x96/0xc0 do_syscall_64+0x54/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fcc04514f9b Code: Unable to access opcode bytes at 0x7fcc04514f71. RSP: 002b:00007ffeba923370 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fcc04514f9b RDX: 00007ffeba923460 RSI: 00000000c4009420 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000013 R09: 0000000000000001 R10: 00007fcc043fbba8 R11: 0000000000000246 R12: 00007ffeba924fc5 R13: 00007ffeba923460 R14: 0000000000000002 R15: 00000000004d4bb0 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__blk_rq_map_sg+0x339/0x4a0 RSP: 0018:ffffc90001a43820 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffea00045d4802 RDX: 0000000117520000 RSI: 0000000000000000 RDI: ffff8881027d1000 RBP: 0000000000003000 R08: ffffea00045d4902 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000001000 R12: ffff8881003d10b8 R13: ffffc90001a438f0 R14: 0000000000000000 R15: 0000000000003000 FS: 00007fcc048a6900(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcc04514f71 CR3: 00000001109ea001 CR4: 0000000000370eb0 Kernel p ---truncated---
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-617

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