CVE-2026-45957
published 2026-05-27CVE-2026-45957: In the Linux kernel, the following vulnerability has been resolved: rcu: Fix rcu_read_unlock() deadloop due to softirq Commit 5f5fa7ea89dc ("rcu: Don't use…
In the Linux kernel, the following vulnerability has been resolved:
rcu: Fix rcu_read_unlock() deadloop due to softirq
Commit 5f5fa7ea89dc ("rcu: Don't use negative nesting depth in
__rcu_read_unlock()") removes the recursion-protection code from
__rcu_read_unlock(). Therefore, we could invoke the deadloop in
raise_softirq_irqoff() with ftrace enabled as follows:
WARNING: CPU: 0 PID: 0 at kernel/trace/trace.c:3021 __ftrace_trace_stack.constprop.0+0x172/0x180
Modules linked in: my_irq_work(O)
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G O 6.18.0-rc7-dirty #23 PREEMPT(full)
Tainted: [O]=OOT_MODULE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:__ftrace_trace_stack.constprop.0+0x172/0x180
RSP: 0018:ffffc900000034a8 EFLAGS: 00010002
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000
RDX: 0000000000000003 RSI: ffffffff826d7b87 RDI: ffffffff826e9329
RBP: 0000000000090009 R08: 0000000000000005 R09: ffffffff82afbc4c
R10: 0000000000000008 R11: 0000000000011d7a R12: 0000000000000000
R13: ffff888003874100 R14: 0000000000000003 R15: ffff8880038c1054
FS: 0000000000000000(0000) GS:ffff8880fa8ea000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b31fa7f540 CR3: 00000000078f4005 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
trace_buffer_unlock_commit_regs+0x6d/0x220
trace_event_buffer_commit+0x5c/0x260
trace_event_raw_event_softirq+0x47/0x80
raise_softirq_irqoff+0x6e/0xa0
rcu_read_unlock_special+0xb1/0x160
unwind_next_frame+0x203/0x9b0
__unwind_start+0x15d/0x1c0
arch_stack_walk+0x62/0xf0
stack_trace_save+0x48/0x70
__ftrace_trace_stack.constprop.0+0x144/0x180
trace_buffer_unlock_commit_regs+0x6d/0x220
trace_event_buffer_commit+0x5c/0x260
trace_event_raw_event_softirq+0x47/0x80
raise_softirq_irqoff+0x6e/0xa0
rcu_read_unlock_special+0xb1/0x160
unwind_next_frame+0x203/0x9b0
__unwind_start+0x15d/0x1c0
arch_stack_walk+0x62/0xf0
stack_trace_save+0x48/0x70
__ftrace_trace_stack.const
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= 5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < 979c708e6c9d7fc461daef2dad8b45f22e23464c | 979c708e6c9d7fc461daef2dad8b45f22e23464c |
| linux | linux | >= 5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < 1f16679a5aa60238466ce339c35f5e82ece60337 | 1f16679a5aa60238466ce339c35f5e82ece60337 |
| linux | linux | >= 5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < 4a4a6e12c9c829be3f74b7206fa8640fc4e1c566 | 4a4a6e12c9c829be3f74b7206fa8640fc4e1c566 |
| linux | linux | >= 5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < c2932e16d8c354404b17123e64daa8e33191e145 | c2932e16d8c354404b17123e64daa8e33191e145 |
| linux | linux | >= 5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < d41e37f26b3157b3f1d10223863519a943aa239b | d41e37f26b3157b3f1d10223863519a943aa239b |
| linux | linux_kernel | — | — |