CVE-2023-53100

Published May 2, 2025

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ext4: fix WARNING in ext4_update_inline_data Syzbot found the following issue: EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 without journal. Quota mode: none. fscrypt: AES-256-CTS-CBC using implementation "cts-cbc-aes-aesni" fscrypt: AES-256-XTS using implementation "xts-aes-aesni" ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5071 at mm/page_alloc.c:5525 __alloc_pages+0x30a/0x560 mm/page_alloc.c:5525 Modules linked in: CPU: 1 PID: 5071 Comm: syz-executor263 Not tainted 6.2.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:__alloc_pages+0x30a/0x560 mm/page_alloc.c:5525 RSP: 0018:ffffc90003c2f1c0 EFLAGS: 00010246 RAX: ffffc90003c2f220 RBX: 0000000000000014 RCX: 0000000000000000 RDX: 0000000000000028 RSI: 0000000000000000 RDI: ffffc90003c2f248 RBP: ffffc90003c2f2d8 R08: dffffc0000000000 R09: ffffc90003c2f220 R10: fffff52000785e49 R11: 1ffff92000785e44 R12: 0000000000040d40 R13: 1ffff92000785e40 R14: dffffc0000000000 R15: 1ffff92000785e3c FS: 0000555556c0d300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f95d5e04138 CR3: 00000000793aa000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_pages_node include/linux/gfp.h:260 [inline] __kmalloc_large_node+0x95/0x1e0 mm/slab_common.c:1113 __do_kmalloc_node mm/slab_common.c:956 [inline] __kmalloc+0xfe/0x190 mm/slab_common.c:981 kmalloc include/linux/slab.h:584 [inline] kzalloc include/linux/slab.h:720 [inline] ext4_update_inline_data+0x236/0x6b0 fs/ext4/inline.c:346 ext4_update_inline_dir fs/ext4/inline.c:1115 [inline] ext4_try_add_inline_entry+0x328/0x990 fs/ext4/inline.c:1307 ext4_add_entry+0x5a4/0xeb0 fs/ext4/namei.c:2385 ext4_add_nondir+0x96/0x260 fs/ext4/namei.c:2772 ext4_create+0x36c/0x560 fs/ext4/namei.c:2817 lookup_open fs/namei.c:3413 [inline] open_last_lookups fs/namei.c:3481 [inline] path_openat+0x12ac/0x2dd0 fs/namei.c:3711 do_filp_open+0x264/0x4f0 fs/namei.c:3741 do_sys_openat2+0x124/0x4e0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_openat fs/open.c:1342 [inline] __se_sys_openat fs/open.c:1337 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Above issue happens as follows: ext4_iget ext4_find_inline_data_nolock ->i_inline_off=164 i_inline_size=60 ext4_try_add_inline_entry __ext4_mark_inode_dirty ext4_expand_extra_isize_ea ->i_extra_isize=32 s_want_extra_isize=44 ext4_xattr_shift_entries ->after shift i_inline_off is incorrect, actually is change to 176 ext4_try_add_inline_entry ext4_update_inline_dir get_max_inline_xattr_value_size if (EXT4_I(inode)->i_inline_off) entry = (struct ext4_xattr_entry *)((void *)raw_inode + EXT4_I(inode)->i_inline_off); free += EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size)); ->As entry is incorrect, then 'free' may be negative ext4_update_inline_data value = kzalloc(len, GFP_NOFS); -> len is unsigned int, maybe very large, then trigger warning when 'kzalloc()' To resolve the above issue we need to update 'i_inline_off' after 'ext4_xattr_shift_entries()'. We do not need to set EXT4_STATE_MAY_INLINE_DATA flag here, since ext4_mark_inode_dirty() already sets this flag if needed. Setting EXT4_STATE_MAY_INLINE_DATA when it is needed may trigger a BUG_ON in ext4_writepages().
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
NVD-CWE-noinfo

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