CVE-2021-47300 (GCVE-0-2021-47300)
Vulnerability from cvelistv5 – Published: 2024-05-21 14:35 – Updated: 2026-08-05 08:47
VLAI
EPSS
VEX
Title
bpf: Fix tail_call_reachable rejection for interpreter when jit failed
Summary
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix tail_call_reachable rejection for interpreter when jit failed
During testing of f263a81451c1 ("bpf: Track subprog poke descriptors correctly
and fix use-after-free") under various failure conditions, for example, when
jit_subprogs() fails and tries to clean up the program to be run under the
interpreter, we ran into the following freeze:
[...]
#127/8 tailcall_bpf2bpf_3:FAIL
[...]
[ 92.041251] BUG: KASAN: slab-out-of-bounds in ___bpf_prog_run+0x1b9d/0x2e20
[ 92.042408] Read of size 8 at addr ffff88800da67f68 by task test_progs/682
[ 92.043707]
[ 92.044030] CPU: 1 PID: 682 Comm: test_progs Tainted: G O 5.13.0-53301-ge6c08cb33a30-dirty #87
[ 92.045542] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014
[ 92.046785] Call Trace:
[ 92.047171] ? __bpf_prog_run_args64+0xc0/0xc0
[ 92.047773] ? __bpf_prog_run_args32+0x8b/0xb0
[ 92.048389] ? __bpf_prog_run_args64+0xc0/0xc0
[ 92.049019] ? ktime_get+0x117/0x130
[...] // few hundred [similar] lines more
[ 92.659025] ? ktime_get+0x117/0x130
[ 92.659845] ? __bpf_prog_run_args64+0xc0/0xc0
[ 92.660738] ? __bpf_prog_run_args32+0x8b/0xb0
[ 92.661528] ? __bpf_prog_run_args64+0xc0/0xc0
[ 92.662378] ? print_usage_bug+0x50/0x50
[ 92.663221] ? print_usage_bug+0x50/0x50
[ 92.664077] ? bpf_ksym_find+0x9c/0xe0
[ 92.664887] ? ktime_get+0x117/0x130
[ 92.665624] ? kernel_text_address+0xf5/0x100
[ 92.666529] ? __kernel_text_address+0xe/0x30
[ 92.667725] ? unwind_get_return_address+0x2f/0x50
[ 92.668854] ? ___bpf_prog_run+0x15d4/0x2e20
[ 92.670185] ? ktime_get+0x117/0x130
[ 92.671130] ? __bpf_prog_run_args64+0xc0/0xc0
[ 92.672020] ? __bpf_prog_run_args32+0x8b/0xb0
[ 92.672860] ? __bpf_prog_run_args64+0xc0/0xc0
[ 92.675159] ? ktime_get+0x117/0x130
[ 92.677074] ? lock_is_held_type+0xd5/0x130
[ 92.678662] ? ___bpf_prog_run+0x15d4/0x2e20
[ 92.680046] ? ktime_get+0x117/0x130
[ 92.681285] ? __bpf_prog_run32+0x6b/0x90
[ 92.682601] ? __bpf_prog_run64+0x90/0x90
[ 92.683636] ? lock_downgrade+0x370/0x370
[ 92.684647] ? mark_held_locks+0x44/0x90
[ 92.685652] ? ktime_get+0x117/0x130
[ 92.686752] ? lockdep_hardirqs_on+0x79/0x100
[ 92.688004] ? ktime_get+0x117/0x130
[ 92.688573] ? __cant_migrate+0x2b/0x80
[ 92.689192] ? bpf_test_run+0x2f4/0x510
[ 92.689869] ? bpf_test_timer_continue+0x1c0/0x1c0
[ 92.690856] ? rcu_read_lock_bh_held+0x90/0x90
[ 92.691506] ? __kasan_slab_alloc+0x61/0x80
[ 92.692128] ? eth_type_trans+0x128/0x240
[ 92.692737] ? __build_skb+0x46/0x50
[ 92.693252] ? bpf_prog_test_run_skb+0x65e/0xc50
[ 92.693954] ? bpf_prog_test_run_raw_tp+0x2d0/0x2d0
[ 92.694639] ? __fget_light+0xa1/0x100
[ 92.695162] ? bpf_prog_inc+0x23/0x30
[ 92.695685] ? __sys_bpf+0xb40/0x2c80
[ 92.696324] ? bpf_link_get_from_fd+0x90/0x90
[ 92.697150] ? mark_held_locks+0x24/0x90
[ 92.698007] ? lockdep_hardirqs_on_prepare+0x124/0x220
[ 92.699045] ? finish_task_switch+0xe6/0x370
[ 92.700072] ? lockdep_hardirqs_on+0x79/0x100
[ 92.701233] ? finish_task_switch+0x11d/0x370
[ 92.702264] ? __switch_to+0x2c0/0x740
[ 92.703148] ? mark_held_locks+0x24/0x90
[ 92.704155] ? __x64_sys_bpf+0x45/0x50
[ 92.705146] ? do_syscall_64+0x35/0x80
[ 92.706953] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
[...]
Turns out that the program rejection from e411901c0b77 ("bpf: allow for tailcalls
in BPF subprograms for x64 JIT") is buggy since env->prog->aux->tail_call_reachable
is never true. Commit ebf7d1f508a7 ("bpf, x64: rework pro/epilogue and tailcall
handling in JIT") added a tracker into check_max_stack_depth() which propagates
the tail_call_reachable condition throughout the subprograms. This info is then
assigned to the subprogram's
---truncated---
Severity
7.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-07-24 17:11 UTC
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| Linux | Linux |
Affected:
ebf7d1f508a73871acf3b2bfbfa1323a477acdb3 , < 39f1735c8107ef43a53c4daf82f330d880488d8f
(git)
Affected: ebf7d1f508a73871acf3b2bfbfa1323a477acdb3 , < cbb086074dab631ac43f8645cbac1d7b148e05c4 (git) Affected: ebf7d1f508a73871acf3b2bfbfa1323a477acdb3 , < 5dd0a6b8582ffbfa88351949d50eccd5b6694ade (git) |
|
| Linux | Linux |
Affected:
5.10
Unaffected: 0 , < 5.10 (semver) Unaffected: 5.10.54 , ≤ 5.10.* (semver) Unaffected: 5.13.6 , ≤ 5.13.* (semver) Unaffected: 5.14 , ≤ * (original_commit_for_fix) |
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix tail_call_reachable rejection for interpreter when jit failed\n\nDuring testing of f263a81451c1 (\"bpf: Track subprog poke descriptors correctly\nand fix use-after-free\") under various failure conditions, for example, when\njit_subprogs() fails and tries to clean up the program to be run under the\ninterpreter, we ran into the following freeze:\n\n [...]\n #127/8 tailcall_bpf2bpf_3:FAIL\n [...]\n [ 92.041251] BUG: KASAN: slab-out-of-bounds in ___bpf_prog_run+0x1b9d/0x2e20\n [ 92.042408] Read of size 8 at addr ffff88800da67f68 by task test_progs/682\n [ 92.043707]\n [ 92.044030] CPU: 1 PID: 682 Comm: test_progs Tainted: G O 5.13.0-53301-ge6c08cb33a30-dirty #87\n [ 92.045542] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014\n [ 92.046785] Call Trace:\n [ 92.047171] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.047773] ? __bpf_prog_run_args32+0x8b/0xb0\n [ 92.048389] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.049019] ? ktime_get+0x117/0x130\n [...] // few hundred [similar] lines more\n [ 92.659025] ? ktime_get+0x117/0x130\n [ 92.659845] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.660738] ? __bpf_prog_run_args32+0x8b/0xb0\n [ 92.661528] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.662378] ? print_usage_bug+0x50/0x50\n [ 92.663221] ? print_usage_bug+0x50/0x50\n [ 92.664077] ? bpf_ksym_find+0x9c/0xe0\n [ 92.664887] ? ktime_get+0x117/0x130\n [ 92.665624] ? kernel_text_address+0xf5/0x100\n [ 92.666529] ? __kernel_text_address+0xe/0x30\n [ 92.667725] ? unwind_get_return_address+0x2f/0x50\n [ 92.668854] ? ___bpf_prog_run+0x15d4/0x2e20\n [ 92.670185] ? ktime_get+0x117/0x130\n [ 92.671130] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.672020] ? __bpf_prog_run_args32+0x8b/0xb0\n [ 92.672860] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.675159] ? ktime_get+0x117/0x130\n [ 92.677074] ? lock_is_held_type+0xd5/0x130\n [ 92.678662] ? ___bpf_prog_run+0x15d4/0x2e20\n [ 92.680046] ? ktime_get+0x117/0x130\n [ 92.681285] ? __bpf_prog_run32+0x6b/0x90\n [ 92.682601] ? __bpf_prog_run64+0x90/0x90\n [ 92.683636] ? lock_downgrade+0x370/0x370\n [ 92.684647] ? mark_held_locks+0x44/0x90\n [ 92.685652] ? ktime_get+0x117/0x130\n [ 92.686752] ? lockdep_hardirqs_on+0x79/0x100\n [ 92.688004] ? ktime_get+0x117/0x130\n [ 92.688573] ? __cant_migrate+0x2b/0x80\n [ 92.689192] ? bpf_test_run+0x2f4/0x510\n [ 92.689869] ? bpf_test_timer_continue+0x1c0/0x1c0\n [ 92.690856] ? rcu_read_lock_bh_held+0x90/0x90\n [ 92.691506] ? __kasan_slab_alloc+0x61/0x80\n [ 92.692128] ? eth_type_trans+0x128/0x240\n [ 92.692737] ? __build_skb+0x46/0x50\n [ 92.693252] ? bpf_prog_test_run_skb+0x65e/0xc50\n [ 92.693954] ? bpf_prog_test_run_raw_tp+0x2d0/0x2d0\n [ 92.694639] ? __fget_light+0xa1/0x100\n [ 92.695162] ? bpf_prog_inc+0x23/0x30\n [ 92.695685] ? __sys_bpf+0xb40/0x2c80\n [ 92.696324] ? bpf_link_get_from_fd+0x90/0x90\n [ 92.697150] ? mark_held_locks+0x24/0x90\n [ 92.698007] ? lockdep_hardirqs_on_prepare+0x124/0x220\n [ 92.699045] ? finish_task_switch+0xe6/0x370\n [ 92.700072] ? lockdep_hardirqs_on+0x79/0x100\n [ 92.701233] ? finish_task_switch+0x11d/0x370\n [ 92.702264] ? __switch_to+0x2c0/0x740\n [ 92.703148] ? mark_held_locks+0x24/0x90\n [ 92.704155] ? __x64_sys_bpf+0x45/0x50\n [ 92.705146] ? do_syscall_64+0x35/0x80\n [ 92.706953] ? entry_SYSCALL_64_after_hwframe+0x44/0xae\n [...]\n\nTurns out that the program rejection from e411901c0b77 (\"bpf: allow for tailcalls\nin BPF subprograms for x64 JIT\") is buggy since env-\u003eprog-\u003eaux-\u003etail_call_reachable\nis never true. Commit ebf7d1f508a7 (\"bpf, x64: rework pro/epilogue and tailcall\nhandling in JIT\") added a tracker into check_max_stack_depth() which propagates\nthe tail_call_reachable condition throughout the subprograms. This info is then\nassigned to the subprogram\u0027s \n---truncated---"
},
{
"lang": "es",
"value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: bpf: corrige el rechazo de tail_call_reachable para el int\u00e9rprete cuando falla jit. Durante las pruebas de f263a81451c1 (\"bpf: rastrea correctamente los descriptores de inserci\u00f3n del subprog y corrige el use after free\") bajo varias condiciones de fallo, por Por ejemplo, cuando jit_subprogs() falla e intenta limpiar el programa que se ejecutar\u00e1 bajo el int\u00e9rprete, nos encontramos con el siguiente congelamiento: [...] #127/8 tailcall_bpf2bpf_3:FAIL [...] [ 92.041251] ERROR: KASAN: slab fuera de los l\u00edmites en ___bpf_prog_run+0x1b9d/0x2e20 [92.042408] Lectura de tama\u00f1o 8 en la direcci\u00f3n ffff88800da67f68 por tarea test_progs/682 [92.043707] [92.044030] CPU: 1 PID: 682 Comm: _progs Contaminado: GO 5.13. 0-53301-ge6c08cb33a30-dirty #87 [92.045542] Nombre del hardware: PC est\u00e1ndar QEMU (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 01/04/2014 [92.046785] Seguimiento de llamadas: [92.047171] ? __bpf_prog_run_args64+0xc0/0xc0 [92.047773]? __bpf_prog_run_args32+0x8b/0xb0 [92.048389]? __bpf_prog_run_args64+0xc0/0xc0 [92.049019]? ktime_get+0x117/0x130 [...] // \u00bfunos cientos de l\u00edneas [similares] m\u00e1s [92.659025]? ktime_get+0x117/0x130 [92.659845]? __bpf_prog_run_args64+0xc0/0xc0 [92.660738]? __bpf_prog_run_args32+0x8b/0xb0 [92.661528]? __bpf_prog_run_args64+0xc0/0xc0 [92.662378]? print_usage_bug+0x50/0x50 [92.663221]? print_usage_bug+0x50/0x50 [92.664077]? bpf_ksym_find+0x9c/0xe0 [92.664887]? ktime_get+0x117/0x130 [92.665624]? kernel_text_address+0xf5/0x100 [92.666529]? __kernel_text_address+0xe/0x30 [ 92.667725] ? unwind_get_return_address+0x2f/0x50 [92.668854]? ___bpf_prog_run+0x15d4/0x2e20 [ 92.670185] ? ktime_get+0x117/0x130 [92.671130]? __bpf_prog_run_args64+0xc0/0xc0 [92.672020]? __bpf_prog_run_args32+0x8b/0xb0 [92.672860]? __bpf_prog_run_args64+0xc0/0xc0 [92.675159]? ktime_get+0x117/0x130 [92.677074]? lock_is_held_type+0xd5/0x130 [92.678662]? ___bpf_prog_run+0x15d4/0x2e20 [ 92.680046] ? ktime_get+0x117/0x130 [92.681285]? __bpf_prog_run32+0x6b/0x90 [92.682601]? __bpf_prog_run64+0x90/0x90 [92.683636]? lock_downgrade+0x370/0x370 [92.684647]? mark_held_locks+0x44/0x90 [92.685652]? ktime_get+0x117/0x130 [92.686752]? lockdep_hardirqs_on+0x79/0x100 [92.688004]? ktime_get+0x117/0x130 [92.688573]? __cant_migrate+0x2b/0x80 [ 92.689192] ? bpf_test_run+0x2f4/0x510 [92.689869]? bpf_test_timer_continue+0x1c0/0x1c0 [92.690856]? rcu_read_lock_bh_held+0x90/0x90 [92.691506]? __kasan_slab_alloc+0x61/0x80 [92.692128]? eth_type_trans+0x128/0x240 [92.692737]? __build_skb+0x46/0x50 [92.693252]? bpf_prog_test_run_skb+0x65e/0xc50 [92.693954]? bpf_prog_test_run_raw_tp+0x2d0/0x2d0 [92.694639]? __fget_light+0xa1/0x100 [ 92.695162] ? bpf_prog_inc+0x23/0x30 [92.695685]? __sys_bpf+0xb40/0x2c80 [92.696324]? bpf_link_get_from_fd+0x90/0x90 [92.697150]? mark_held_locks+0x24/0x90 [92.698007]? lockdep_hardirqs_on_prepare+0x124/0x220 [92.699045]? finish_task_switch+0xe6/0x370 [92.700072]? lockdep_hardirqs_on+0x79/0x100 [92.701233]? finish_task_switch+0x11d/0x370 [92.702264]? __switch_to+0x2c0/0x740 [ 92.703148] ? mark_held_locks+0x24/0x90 [92.704155]? __x64_sys_bpf+0x45/0x50 [92.705146]? do_syscall_64+0x35/0x80 [92.706953]? Entry_SYSCALL_64_after_hwframe+0x44/0xae [...] Resulta que el rechazo del programa de e411901c0b77 (\"bpf: permitir tailcalls en subprogramas BPF para x64 JIT\") tiene errores ya que env-\u0026gt;prog-\u0026gt;aux-\u0026gt;tail_call_reachable nunca es cierto. La confirmaci\u00f3n ebf7d1f508a7 (\"bpf, x64: reelaboraci\u00f3n de pro/ep\u00edlogo y manejo de tailcall en JIT\") agreg\u00f3 un rastreador en check_max_stack_ Depth() que propaga la condici\u00f3n tail_call_reachable a trav\u00e9s de los subprogramas. Esta informaci\u00f3n luego se asigna al ---truncado--- del subprograma."
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{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix tail_call_reachable rejection for interpreter when jit failed\n\nDuring testing of f263a81451c1 (\"bpf: Track subprog poke descriptors correctly\nand fix use-after-free\") under various failure conditions, for example, when\njit_subprogs() fails and tries to clean up the program to be run under the\ninterpreter, we ran into the following freeze:\n\n [...]\n #127/8 tailcall_bpf2bpf_3:FAIL\n [...]\n [ 92.041251] BUG: KASAN: slab-out-of-bounds in ___bpf_prog_run+0x1b9d/0x2e20\n [ 92.042408] Read of size 8 at addr ffff88800da67f68 by task test_progs/682\n [ 92.043707]\n [ 92.044030] CPU: 1 PID: 682 Comm: test_progs Tainted: G O 5.13.0-53301-ge6c08cb33a30-dirty #87\n [ 92.045542] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014\n [ 92.046785] Call Trace:\n [ 92.047171] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.047773] ? __bpf_prog_run_args32+0x8b/0xb0\n [ 92.048389] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.049019] ? ktime_get+0x117/0x130\n [...] // few hundred [similar] lines more\n [ 92.659025] ? ktime_get+0x117/0x130\n [ 92.659845] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.660738] ? __bpf_prog_run_args32+0x8b/0xb0\n [ 92.661528] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.662378] ? print_usage_bug+0x50/0x50\n [ 92.663221] ? print_usage_bug+0x50/0x50\n [ 92.664077] ? bpf_ksym_find+0x9c/0xe0\n [ 92.664887] ? ktime_get+0x117/0x130\n [ 92.665624] ? kernel_text_address+0xf5/0x100\n [ 92.666529] ? __kernel_text_address+0xe/0x30\n [ 92.667725] ? unwind_get_return_address+0x2f/0x50\n [ 92.668854] ? ___bpf_prog_run+0x15d4/0x2e20\n [ 92.670185] ? ktime_get+0x117/0x130\n [ 92.671130] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.672020] ? __bpf_prog_run_args32+0x8b/0xb0\n [ 92.672860] ? __bpf_prog_run_args64+0xc0/0xc0\n [ 92.675159] ? ktime_get+0x117/0x130\n [ 92.677074] ? lock_is_held_type+0xd5/0x130\n [ 92.678662] ? ___bpf_prog_run+0x15d4/0x2e20\n [ 92.680046] ? ktime_get+0x117/0x130\n [ 92.681285] ? __bpf_prog_run32+0x6b/0x90\n [ 92.682601] ? __bpf_prog_run64+0x90/0x90\n [ 92.683636] ? lock_downgrade+0x370/0x370\n [ 92.684647] ? mark_held_locks+0x44/0x90\n [ 92.685652] ? ktime_get+0x117/0x130\n [ 92.686752] ? lockdep_hardirqs_on+0x79/0x100\n [ 92.688004] ? ktime_get+0x117/0x130\n [ 92.688573] ? __cant_migrate+0x2b/0x80\n [ 92.689192] ? bpf_test_run+0x2f4/0x510\n [ 92.689869] ? bpf_test_timer_continue+0x1c0/0x1c0\n [ 92.690856] ? rcu_read_lock_bh_held+0x90/0x90\n [ 92.691506] ? __kasan_slab_alloc+0x61/0x80\n [ 92.692128] ? eth_type_trans+0x128/0x240\n [ 92.692737] ? __build_skb+0x46/0x50\n [ 92.693252] ? bpf_prog_test_run_skb+0x65e/0xc50\n [ 92.693954] ? bpf_prog_test_run_raw_tp+0x2d0/0x2d0\n [ 92.694639] ? __fget_light+0xa1/0x100\n [ 92.695162] ? bpf_prog_inc+0x23/0x30\n [ 92.695685] ? __sys_bpf+0xb40/0x2c80\n [ 92.696324] ? bpf_link_get_from_fd+0x90/0x90\n [ 92.697150] ? mark_held_locks+0x24/0x90\n [ 92.698007] ? lockdep_hardirqs_on_prepare+0x124/0x220\n [ 92.699045] ? finish_task_switch+0xe6/0x370\n [ 92.700072] ? lockdep_hardirqs_on+0x79/0x100\n [ 92.701233] ? finish_task_switch+0x11d/0x370\n [ 92.702264] ? __switch_to+0x2c0/0x740\n [ 92.703148] ? mark_held_locks+0x24/0x90\n [ 92.704155] ? __x64_sys_bpf+0x45/0x50\n [ 92.705146] ? do_syscall_64+0x35/0x80\n [ 92.706953] ? entry_SYSCALL_64_after_hwframe+0x44/0xae\n [...]\n\nTurns out that the program rejection from e411901c0b77 (\"bpf: allow for tailcalls\nin BPF subprograms for x64 JIT\") is buggy since env-\u003eprog-\u003eaux-\u003etail_call_reachable\nis never true. Commit ebf7d1f508a7 (\"bpf, x64: rework pro/epilogue and tailcall\nhandling in JIT\") added a tracker into check_max_stack_depth() which propagates\nthe tail_call_reachable condition throughout the subprograms. This info is then\nassigned to the subprogram\u0027s \n---truncated---"
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The bug is reached only via the local bpf() syscall (BPF_PROG_LOAD \u2192 verifier fixup_call_args, then program execution such as BPF_PROG_TEST_RUN), not by parsing remote network input; BPF is scored Local per kernel CNA guidance.\nAC:L - A CAP_BPF attacker fully controls the bpf2bpf+tailcall program and can force jit_subprogs() failure (e.g., exhausting executable/JIT allocations so bpf_int_jit_compile/bpf_prog_alloc fails), which deterministically falls through to the broken interpreter rejection path with no race required.\nPR:L - bpf-to-bpf calls require bpf_capable() (CAP_BPF/CAP_SYS_ADMIN in init_user_ns); per kernel CNA BPF scoring precedent CAP_BPF-gated loading is Low privilege, not full root/admin.\nUI:N - The attacker loads the crafted program and triggers execution themselves (e.g., BPF_PROG_TEST_RUN or an attach point they control); no separate victim action is required.\nS:U - Impact stays within the host kernel\u2019s BPF/interpreter authority (local memory-safety failure and DoS/privilege escalation); it does not cross a VM, IOMMU, or other distinct security boundary.\nC:H - The fixed failure path produced a KASAN slab-out-of-bounds read in ___bpf_prog_run; per guidance an OOB read is Confidentiality High unless strictly bounded to a few bytes.\nI:H - Unsupported interpreter execution of bpf2bpf combined with tail calls causes unbounded recursive interpreter frames and kernel stack overflow/memory corruption, which under the overestimate rule is treated as Integrity High (exploitable corruption/control-flow impact).\nA:H - The commit documents a kernel freeze with hundreds of recursive ___bpf_prog_run frames and a KASAN-detected crash path, which is Availability High (hang/oops/panic)."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-05T08:47:09.253Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/39f1735c8107ef43a53c4daf82f330d880488d8f"
},
{
"url": "https://git.kernel.org/stable/c/cbb086074dab631ac43f8645cbac1d7b148e05c4"
},
{
"url": "https://git.kernel.org/stable/c/5dd0a6b8582ffbfa88351949d50eccd5b6694ade"
}
],
"title": "bpf: Fix tail_call_reachable rejection for interpreter when jit failed",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2021-47300",
"datePublished": "2024-05-21T14:35:22.040Z",
"dateReserved": "2024-05-21T13:27:52.132Z",
"dateUpdated": "2026-08-05T08:47:09.253Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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