CVE-2022-49372
tcp: tcp_rtx_synack() can be called from process context
Summary
Descriptions
In the Linux kernel, the following vulnerability has been resolved: tcp: tcp_rtx_synack() can be called from process context Laurent reported the enclosed report [1] This bug triggers with following coditions: 0) Kernel built with CONFIG_DEBUG_PREEMPT=y 1) A new passive FastOpen TCP socket is created. This FO socket waits for an ACK coming from client to be a complete ESTABLISHED one.
2) A socket operation on this socket goes through lock_sock() release_sock() dance.
3) While the socket is owned by the user in step 2), a retransmit of the SYN is received and stored in socket backlog.
4) At release_sock() time, the socket backlog is processed while in process context.
5) A SYNACK packet is cooked in response of the SYN retransmit.
6) -> tcp_rtx_synack() is called in process context. Before blamed commit, tcp_rtx_synack() was always called from BH handler,
from a timer handler. Fix this by using TCP_INC_STATS() & NET_INC_STATS()
which do not assume caller is in non preemptible context. [1]
BUG: using __this_cpu_add() in preemptible [00000000] code: epollpep/2180
caller is tcp_rtx_synack.part.0+0x36/0xc0
CPU: 10 PID: 2180 Comm: epollpep Tainted: G OE 5.16.0-0.bpo.4-amd64 #1 Debian 5.16.12-1~bpo11+1
Hardware name: Supermicro SYS-5039MC-H8TRF/X11SCD-F, BIOS 1.7 11/23/2021
Call Trace: <TASK> dump_stack_lvl+0x48/0x5e check_preemption_disabled+0xde/0xe0 tcp_rtx_synack.part.0+0x36/0xc0 tcp_rtx_synack+0x8d/0xa0 ? kmem_cache_alloc+0x2e0/0x3e0 ? apparmor_file_alloc_security+0x3b/0x1f0 inet_rtx_syn_ack+0x16/0x30 tcp_check_req+0x367/0x610 tcp_rcv_state_process+0x91/0xf60 ? get_nohz_timer_target+0x18/0x1a0 ? lock_timer_base+0x61/0x80 ? preempt_count_add+0x68/0xa0 tcp_v4_do_rcv+0xbd/0x270 __release_sock+0x6d/0xb0 release_sock+0x2b/0x90 sock_setsockopt+0x138/0x1140 ? __sys_getsockname+0x7e/0xc0 ? aa_sk_perm+0x3e/0x1a0 __sys_setsockopt+0x198/0x1e0 __x64_sys_setsockopt+0x21/0x30 do_syscall_64+0x38/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae
CVSS Scores
SSVC
- Decision:-
Timeline
- 2025-02-26 CVE Reserved
- 2025-02-26 CVE Published
- 2025-02-26 CVE Updated
- ---------- EPSS Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
CAPEC
Threat Intelligence Resources (0)
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References (10)
| URL | Tag | Source |
|---|---|---|
| https://git.kernel.org/stable/c/168a8f58059a22feb9e9a2dcc1b8053dbbbc12ef | Vuln. Introduced |
| URL | Date | SRC |
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Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 4.9.318 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 4.9.318" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 4.14.283 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 4.14.283" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 4.19.247 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 4.19.247" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 5.4.198 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 5.4.198" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 5.10.122 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 5.10.122" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 5.15.47 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 5.15.47" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 5.17.15 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 5.17.15" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 5.18.4 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 5.18.4" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 3.7 < 5.19 Search vendor "Linux" for product "Linux Kernel" and version " >= 3.7 < 5.19" | en |
Affected
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