Summary
In the Linux kernel, the following vulnerability has been resolved: jfs: Fix null-ptr-deref in...
In the Linux kernel, the following vulnerability has been resolved:
jfs: Fix null-ptr-deref in jfs_ioc_trim
[ Syzkaller Report ]
Oops: general protection fault, probably for non-canonical address
0xdffffc0000000087: 0000 [#1
KASAN: null-ptr-deref in range [0x0000000000000438-0x000000000000043f]
CPU: 2 UID: 0 PID: 10614 Comm: syz-executor.0 Not tainted
6.13.0-rc6-gfbfd64d25c7a-dirty #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Sched_ext: serialise (enabled+all), task: runnable_at=-30ms
RIP: 0010:jfs_ioc_trim+0x34b/0x8f0
Code: e7 e8 59 a4 87 fe 4d 8b 24 24 4d 8d bc 24 38 04 00 00 48 8d 93
90 82 fe ff 4c 89 ff 31 f6
RSP: 0018:ffffc900055f7cd0 EFLAGS: 00010206
RAX: 0000000000000087 RBX: 00005866a9e67ff8 RCX: 000000000000000a
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffff88807c180003 R09: 1ffff1100f830000
R10: dffffc0000000000 R11: ffffed100f830001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000438
FS: 00007fe520225640(0000) GS:ffff8880b7e80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005593c91b2c88 CR3: 000000014927c000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
? __die_body+0x61/0xb0
? die_addr+0xb1/0xe0
? exc_general_protection+0x333/0x510
? asm_exc_general_protection+0x26/0x30
? jfs_ioc_trim+0x34b/0x8f0
jfs_ioctl+0x3c8/0x4f0
? __pfx_jfs_ioctl+0x10/0x10
? __pfx_jfs_ioctl+0x10/0x10
__se_sys_ioctl+0x269/0x350
? __pfx___se_sys_ioctl+0x10/0x10
? do_syscall_64+0xfb/0x210
do_syscall_64+0xee/0x210
? syscall_exit_to_user_mode+0x1e0/0x330
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe51f4903ad
Code: c3 e8 a7 2b 00 00 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 89 f8 48
89 f7 48 89 d6 48 89 ca 4d
RSP: 002b:00007fe5202250c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe51f5cbf80 RCX: 00007fe51f4903ad
RDX: 0000000020000680 RSI: 00000000c0185879 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe520225640
R13: 000000000000000e R14: 00007fe51f44fca0 R15: 00007fe52021d000
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:jfs_ioc_trim+0x34b/0x8f0
Code: e7 e8 59 a4 87 fe 4d 8b 24 24 4d 8d bc 24 38 04 00 00 48 8d 93
90 82 fe ff 4c 89 ff 31 f6
RSP: 0018:ffffc900055f7cd0 EFLAGS: 00010206
RAX: 0000000000000087 RBX: 00005866a9e67ff8 RCX: 000000000000000a
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffff88807c180003 R09: 1ffff1100f830000
R10: dffffc0000000000 R11: ffffed100f830001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000438
FS: 00007fe520225640(0000) GS:ffff8880b7e80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005593c91b2c88 CR3: 000000014927c000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Kernel panic - not syncing: Fatal exception
[ Analysis ]
We believe that we have found a concurrency bug in the fs/jfs module
that results in a null pointer dereference. There is a closely related
issue which has been fixed:
... but, unfortunately, the accepted patch appears to still be
susceptible to a null pointer dereference under some interleavings.
To trigger the bug, we think that JFS_SBI(ipbmap->i_sb)->bmap is set
to NULL in dbFreeBits and then dereferenced in jfs_ioc_trim. This
bug manifests quite rarely under normal circumstances, but is
triggereable from a syz-program.
Impact
The application dereferences a null pointer, causing a crash. Typical impact: denial of service via crash.
CVE-2025-38203 has a CVSS score of 5.5 (Medium). The vector is requires local access, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2025-38203? CVE-2025-38203 is a medium-severity null pointer dereference vulnerability. No fixed version is listed yet. The application dereferences a null pointer, causing a crash.
- How severe is CVE-2025-38203? CVE-2025-38203 has a CVSS score of 5.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Is there a fix for CVE-2025-38203? No fixed version is listed for CVE-2025-38203 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-38203 exploitable, and should I be worried? Whether CVE-2025-38203 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-38203 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.