cbcvebase.
CVE-2021-47448
published 2024-05-22

CVE-2021-47448: In the Linux kernel, the following vulnerability has been resolved: mptcp: fix possible stall on recvmsg() recvmsg() can enter an infinite loop if the caller…

PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.47%
38.5th percentile
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix possible stall on recvmsg() recvmsg() can enter an infinite loop if the caller provides the MSG_WAITALL, the data present in the receive queue is not sufficient to fulfill the request, and no more data is received by the peer. When the above happens, mptcp_wait_data() will always return with no wait, as the MPTCP_DATA_READY flag checked by such function is set and never cleared in such code path. Leveraging the above syzbot was able to trigger an RCU stall: rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=0af/1/0x4000000000000000 softirq=10678/10678 fqs=1 (t=10500 jiffies g=13089 q=109) rcu: rcu_preempt kthread starved for 10497 jiffies! g13089 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4955 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6236 schedule+0xd3/0x270 kernel/sched/core.c:6315 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8510 Comm: syz-executor827 Not tainted 5.15.0-rc2-next-20210920-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/k

Affected

13 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.14.16-1 (bookworm)linux 5.14.16-1 (bookworm)
linuxlinux
linuxlinux>= 7a6a6cbc3e592e339ad23e4e8ede9a3f6160bda8 < 1a4554e94f0deff9fc1dc5addf93fa579cc297111a4554e94f0deff9fc1dc5addf93fa579cc29711
linuxlinux>= 7a6a6cbc3e592e339ad23e4e8ede9a3f6160bda8 < 612f71d7328c14369924384ad2170aae2a6abd92612f71d7328c14369924384ad2170aae2a6abd92
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.14.16-15.14.16-1
linuxlinux_kernel>= 0 < 5.14.16-15.14.16-1
linuxlinux_kernel>= 0 < 5.14.16-15.14.16-1
linuxlinux_kernel>= 5.6 < 5.14.145.14.14

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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