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CVE-2025-38279

In the Linux kernel, the following vulnerability has been resolved:

bpf: Do not include stack ptr register in precision backtracking bookkeeping

Yi Lai reported an issue ([1]) where the following warning appears
in kernel dmesg:
  [   60.643604] verifier backtracking bug
  [   60.643635] WARNING: CPU: 10 PID: 2315 at kernel/bpf/verifier.c:4302 __mark_chain_precision+0x3a6c/0x3e10
  [   60.648428] Modules linked in: bpf_testmod(OE)
  [   60.650471] CPU: 10 UID: 0 PID: 2315 Comm: test_progs Tainted: G           OE       6.15.0-rc4-gef11287f8289-dirty #327 PREEMPT(full)
  [   60.654385] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
  [   60.656682] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  [   60.660475] RIP: 0010:__mark_chain_precision+0x3a6c/0x3e10
  [   60.662814] Code: 5a 30 84 89 ea e8 c4 d9 01 00 80 3d 3e 7d d8 04 00 0f 85 60 fa ff ff c6 05 31 7d d8 04
                       01 48 c7 c7 00 58 30 84 e8 c4 06 a5 ff <0f> 0b e9 46 fa ff ff 48 ...
  [   60.668720] RSP: 0018:ffff888116cc7298 EFLAGS: 00010246
  [   60.671075] RAX: 54d70e82dfd31900 RBX: ffff888115b65e20 RCX: 0000000000000000
  [   60.673659] RDX: 0000000000000001 RSI: 0000000000000004 RDI: 00000000ffffffff
  [   60.676241] RBP: 0000000000000400 R08: ffff8881f6f23bd3 R09: 1ffff1103ede477a
  [   60.678787] R10: dffffc0000000000 R11: ffffed103ede477b R12: ffff888115b60ae8
  [   60.681420] R13: 1ffff11022b6cbc4 R14: 00000000fffffff2 R15: 0000000000000001
  [   60.684030] FS:  00007fc2aedd80c0(0000) GS:ffff88826fa8a000(0000) knlGS:0000000000000000
  [   60.686837] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [   60.689027] CR2: 000056325369e000 CR3: 000000011088b002 CR4: 0000000000370ef0
  [   60.691623] Call Trace:
  [   60.692821]  <TASK>
  [   60.693960]  ? __pfx_verbose+0x10/0x10
  [   60.695656]  ? __pfx_disasm_kfunc_name+0x10/0x10
  [   60.697495]  check_cond_jmp_op+0x16f7/0x39b0
  [   60.699237]  do_check+0x58fa/0xab10
  ...

Further analysis shows the warning is at line 4302 as below:

  4294                 /* static subprog call instruction, which
  4295                  * means that we are exiting current subprog,
  4296                  * so only r1-r5 could be still requested as
  4297                  * precise, r0 and r6-r10 or any stack slot in
  4298                  * the current frame should be zero by now
  4299                  */
  4300                 if (bt_reg_mask(bt) & ~BPF_REGMASK_ARGS) {
  4301                         verbose(env, "BUG regs %x\n", bt_reg_mask(bt));
  4302                         WARN_ONCE(1, "verifier backtracking bug");
  4303                         return -EFAULT;
  4304                 }

With the below test (also in the next patch):
  __used __naked static void __bpf_jmp_r10(void)
  {
	asm volatile (
	"r2 = 2314885393468386424 ll;"
	"goto +0;"
	"if r2 <= r10 goto +3;"
	"if r1 >= -1835016 goto +0;"
	"if r2 <= 8 goto +0;"
	"if r3 <= 0 goto +0;"
	"exit;"
	::: __clobber_all);
  }

  SEC("?raw_tp")
  __naked void bpf_jmp_r10(void)
  {
	asm volatile (
	"r3 = 0 ll;"
	"call __bpf_jmp_r10;"
	"r0 = 0;"
	"exit;"
	::: __clobber_all);
  }

The following is the verifier failure log:
  0: (18) r3 = 0x0                      ; R3_w=0
  2: (85) call pc+2
  caller:
   R10=fp0
  callee:
   frame1: R1=ctx() R3_w=0 R10=fp0
  5: frame1: R1=ctx() R3_w=0 R10=fp0
  ; asm volatile ("                                 \ @ verifier_precision.c:184
  5: (18) r2 = 0x20202000256c6c78       ; frame1: R2_w=0x20202000256c6c78
  7: (05) goto pc+0
  8: (bd) if r2 <= r10 goto pc+3        ; frame1: R2_w=0x20202000256c6c78 R10=fp0
  9: (35) if r1 >= 0xffe3fff8 goto pc+0         ; frame1: R1=ctx()
  10: (b5) if r2 <= 0x8 goto pc+0
  mark_precise: frame1: last_idx 10 first_idx 0 subseq_idx -1
  mark_precise: frame1: regs=r2 stack= before 9: (35) if r1 >= 0xffe3fff8 goto pc+0
  mark_precise: frame1: regs=r2 stack= before 8: (bd) if r2 <= r10 goto pc+3
  mark_preci
---truncated---

Verknüpft mit AI von unstrukturierten Daten zu bestehenden CPE der NVD
Diese Information steht angemeldeten Benutzern zur Verfügung.
Daten sind bereitgestellt durch das CVE Programm von einer CVE Numbering Authority (CNA) (Unstrukturiert).
HerstellerLinux
Produkt Linux
Default Statusunaffected
Version < 4265682c29c92f52c0da6fad5a79b5801462c8de
Version 407958a0e980b9e1842ab87b5a1040521e1e24e9
Status affected
Version < ac49b7560b4b08b1e4043a29214cc7ad77644c00
Version 407958a0e980b9e1842ab87b5a1040521e1e24e9
Status affected
Version < e2d2115e56c4a02377189bfc3a9a7933552a7b0f
Version 407958a0e980b9e1842ab87b5a1040521e1e24e9
Status affected
Version fc2778c42f99c7de52fc004157b3c3ee4dcc208a
Status affected
HerstellerLinux
Produkt Linux
Default Statusaffected
Version 6.5
Status affected
Version < 6.5
Version 0
Status unaffected
Version <= 6.12.*
Version 6.12.37
Status unaffected
Version <= 6.15.*
Version 6.15.3
Status unaffected
Version <= *
Version 6.16
Status unaffected
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.03% 0.074
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String