CVE-2025-38267

Description

In the Linux kernel, the following vulnerability has been resolved:ring-buffer: Do not trigger WARN_ON() due to a commit_overrunWhen reading a memory mapped buffer the reader page is just swapped outwith the last page written in the write buffer. If the reader page is thesame as the commit buffer (the buffer that is currently being written to)it was assumed that it should never have missed events. If it does, ittriggers a WARN_ON_ONCE().But there just happens to be one scenario where this can legitimatelyhappen. That is on a commit_overrun. A commit overrun is when an interruptpreempts an event being written to the buffer and then the interrupt addsso many new events that it fills and wraps the buffer back to the commit.Any new events would then be dropped and be reported as missed_events.In this case, the next page to read is the commit buffer and after theswap of the reader page, the reader page will be the commit buffer, butthis time there will be missed events and this triggers the followingwarning: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1127 at kernel/trace/ring_buffer.c:7357 ring_buffer_map_get_reader+0x49a/0x780 Modules linked in: kvm_intel kvm irqbypass CPU: 2 UID: 0 PID: 1127 Comm: trace-cmd Not tainted 6.15.0-rc7-test-00004-g478bc2824b45-dirty #564 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:ring_buffer_map_get_reader+0x49a/0x780 Code: 00 00 00 48 89 fe 48 c1 ee 03 80 3c 2e 00 0f 85 ec 01 00 00 4d 3b a6 a8 00 00 00 0f 85 8a fd ff ff 48 85 c0 0f 84 55 fe ff ff <0f> 0b e9 4e fe ff ff be 08 00 00 00 4c 89 54 24 58 48 89 54 24 50 RSP: 0018:ffff888121787dc0 EFLAGS: 00010002 RAX: 00000000000006a2 RBX: ffff888100062800 RCX: ffffffff8190cb49 RDX: ffff888126934c00 RSI: 1ffff11020200a15 RDI: ffff8881010050a8 RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffed1024d26982 R10: ffff888126934c17 R11: ffff8881010050a8 R12: ffff888126934c00 R13: ffff8881010050b8 R14: ffff888101005000 R15: ffff888126930008 FS: 00007f95c8cd7540(0000) GS:ffff8882b576e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f95c8de4dc0 CR3: 0000000128452002 CR4: 0000000000172ef0 Call Trace: __pfx_ring_buffer_map_get_reader+0x10/0x10 tracing_buffers_ioctl+0x283/0x370 __x64_sys_ioctl+0x134/0x190 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f95c8de48db Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007ffe037ba110 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffe037bb2b0 RCX: 00007f95c8de48db RDX: 0000000000000000 RSI: 0000000000005220 RDI: 0000000000000006 RBP: 00007ffe037ba180 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe037bb6f8 R14: 00007f95c9065000 R15: 00005575c7492c90 irq event stamp: 5080 hardirqs last enabled at (5079): [] _raw_spin_unlock_irqrestore+0x50/0x70 hardirqs last disabled at (5080): [] _raw_spin_lock_irqsave+0x63/0x70 softirqs last enabled at (4182): [] handle_softirqs+0x552/0x710 softirqs last disabled at (4159): [] __irq_exit_rcu+0x107/0x210 ---[ end trace 0000000000000000 ]---The above was triggered by running on a kernel with both lockdep and KASANas well as kmemleak enabled and executing the following command: # perf record -o perf-test.dat -a -- trace-cmd record --nosplice -e all -p function hackbench 50With perf interjecting a lot of interrupts and trace-cmd enabling allevents as well as function tracing, with lockdep, KASAN and kmemleakenabled, it could cause an interrupt preempting an event being written toadd enough event---truncated---

Risk Information

Associated Vulnerability

Patch Details

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234