In the Linux kernel, the following vulnerability has been resolved: jfs: Fix uaf in dbFreeBits [syzbot reported] ================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:587 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0xfe/0xd70 kernel/locking/mutex.c:752 Read of size 8 at addr ffff8880229254b0 by task syz-executor357/5216 CPU: 0 UID: 0 PID: 5216 Comm: syz-executor357 Not tainted 6.11.0-rc3-syzkaller-00156-gd7a5aa4b3c00 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __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 __mutex_lock_common kernel/locking/mutex.c:587 [inline] __mutex_lock+0xfe/0xd70 kernel/locking/mutex.c:752 dbFreeBits+0x7ea/0xd90 fs/jfs/jfs_dmap.c:2390 dbFreeDmap fs/jfs/jfs_dmap.c:2089 [inline] dbFree+0x35b/0x680 fs/jfs/jfs_dmap.c:409 dbDiscardAG+0x8a9/0xa20 fs/jfs/jfs_dmap.c:1650 jfs_ioc_trim+0x433/0x670 fs/jfs/jfs_discard.c:100 jfs_ioctl+0x2d0/0x3e0 fs/jfs/ioctl.c:131 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 Freed by task 5218: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kfree+0x149/0x360 mm/slub.c:4594 dbUnmount+0x11d/0x190 fs/jfs/jfs_dmap.c:278 jfs_mount_rw+0x4ac/0x6a0 fs/jfs/jfs_mount.c:247 jfs_remount+0x3d1/0x6b0 fs/jfs/super.c:454 reconfigure_super+0x445/0x880 fs/super.c:1083 vfs_cmd_reconfigure fs/fsopen.c:263 [inline] vfs_fsconfig_locked fs/fsopen.c:292 [inline] __do_sys_fsconfig fs/fsopen.c:473 [inline] __se_sys_fsconfig+0xb6e/0xf80 fs/fsopen.c:345 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 [Analysis] There are two paths (dbUnmount and jfs_ioc_trim) that generate race condition when accessing bmap, which leads to the occurrence of uaf
Why It Matters
Analysis dossierWhy It Matters
In the Linux kernel, the following vulnerability has been resolved: jfs: Fix uaf in dbFreeBits [syzbot reported] ================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:587 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0xfe/0xd70 kernel/locking/mutex.c:752 Read of size 8 at addr ffff8880229254b0 by task syz-executor357/5216 CPU: 0 UID: 0 PID: 5216 Comm: syz-executor357 Not tainted 6.11.0-rc3-syzkaller-00156-gd7a5aa4b3c00 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __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 __mutex_lock_common kernel/locking/mutex.c:587 [inline] __mutex_lock+0xfe/0xd70 kernel/locking/mutex.c:752 dbFreeBits+0x7ea/0xd90 fs/jfs/jfs_dmap.c:2390 dbFreeDmap fs/jfs/jfs_dmap.c:2089 [inline] dbFree+0x35b/0x680 fs/jfs/jfs_dmap.c:409 dbDiscardAG+0x8a9/0xa20 fs/jfs/jfs_dmap.c:1650 jfs_ioc_trim+0x433/0x670 fs/jfs/jfs_discard.c:100 jfs_ioctl+0x2d0/0x3e0 fs/jfs/ioctl.c:131 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 Freed by task 5218: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kfree+0x149/0x360 mm/slub.c:4594 dbUnmount+0x11d/0x190 fs/jfs/jfs_dmap.c:278 jfs_mount_rw+0x4ac/0x6a0 fs/jfs/jfs_mount.c:247 jfs_remount+0x3d1/0x6b0 fs/jfs/super.c:454 reconfigure_super+0x445/0x880 fs/super.c:1083 vfs_cmd_reconfigure fs/fsopen.c:263 [inline] vfs_fsconfig_locked fs/fsopen.c:292 [inline] __do_sys_fsconfig fs/fsopen.c:473 [inline] __se_sys_fsconfig+0xb6e/0xf80 fs/fsopen.c:345 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 [Analysis] There are two paths (dbUnmount and jfs_ioc_trim) that generate race condition when accessing bmap, which leads to the occurrence of uaf. Use the lock s_umount to synchronize them, in order to avoid uaf caused by race condition.
High
Unknown
Unknown
Risk basis: SOC ecosystem technology relevance; HIGH severity; No confirmed exploitation signal in current enrichment
Affected Products & Remediation
1 source-backed product- linux linux kernel · < 5.10.227; >= 5.11 < 5.15.168; >= 5.16 < 6.1.113; >= 6.2 < 6.6.55; >= 6.7 < 6.10.14; >= 6.11 < 6.11.3 · NVD CPE · Source
Vendor or catalog guidance (source)
Not provided by source
Known exploitation (source facts)
Only what a source states. Unknown means no source has said either way; it is not "not exploited".
- CISA KEV
- Unknown
- Exploited (source statement)
- Unknown
- Publicly disclosed (source)
- Unknown
Suggested hunting (rule-based inference)
SecOps Signal recommendation (rule-based inference). These steps are hunting hypotheses from the vulnerability class; they do not state or imply that exploitation occurred here or anywhere.
Matched local-privilege-escalation (CVSS AV:L, CVSS PR:L)
Exposure
- Identify hosts reporting this CVE, prioritising shared or multi-user systems.Telemetry: DeviceTvmSoftwareVulnerabilities · A local, low-privilege vector matters most where untrusted users can run code. · Rule local-privilege-escalation
Exploitation evidence
- Look for low-privileged processes spawning SYSTEM or root-level child processes on affected hosts.Telemetry: DeviceProcessEvents · Hunting hypothesis from the CVSS vector; privilege transitions are a focused starting point, not evidence of attack. · Rule local-privilege-escalation
Response
- Confirm the source-stated update on affected hosts.Telemetry: DeviceTvmSoftwareVulnerabilities · Host inventory can verify remediation. · Rule local-privilege-escalation
CISA KEV Record
CISA KEV status was not determined for this record.
Change History & Source Data
— No recorded material change
- CNA / source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- Record status · verification
- UPDATED · NVD API
- CPE
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Evidence & Provenance
Linked by the query's stored exact CVE association. Review required tables and validation status before use.
DeviceTvmSoftwareVulnerabilities| where CveId == "CVE-2024-49903"| project DeviceId, DeviceName, OSPlatform, OSVersion, SoftwareVendor, SoftwareName, SoftwareVersion, CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId| sort by VulnerabilitySeverityLevel descCorrelated briefings
— No published briefing references this CVE