CVE-2023-53240
xsk: check IFF_UP earlier in Tx path
Description
In the Linux kernel, the following vulnerability has been resolved: xsk: check IFF_UP earlier in Tx path Xsk Tx can be triggered via either sendmsg() or poll() syscalls. These two paths share a call to common function xsk_xmit() which has two sanity checks within. A pseudo code example to show the two paths: __xsk_sendmsg() : xsk_poll(): if (unlikely(!xsk_is_bound(xs))) if (unlikely(!xsk_is_bound(xs))) return -ENXIO; return mask; if (unlikely(need_wait)) (...) return -EOPNOTSUPP; xsk_xmit() mark napi id (...) xsk_xmit() xsk_xmit(): if (unlikely(!(xs->dev->flags & IFF_UP))) return -ENETDOWN; if (unlikely(!xs->tx)) return -ENOBUFS; As it can be observed above, in sendmsg() napi id can be marked on interface that was not brought up and this causes a NULL ptr dereference: [31757.505631] BUG: kernel NULL pointer dereference, address: 0000000000000018 [31757.512710] #PF: supervisor read access in kernel mode [31757.517936] #PF: error_code(0x0000) - not-present page [31757.523149] PGD 0 P4D 0 [31757.525726] Oops: 0000 [#1] PREEMPT SMP NOPTI [31757.530154] CPU: 26 PID: 95641 Comm: xdpsock Not tainted 6.2.0-rc5+ #40 [31757.536871] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019 [31757.547457] RIP: 0010:xsk_sendmsg+0xde/0x180 [31757.551799] Code: 00 75 a2 48 8b 00 a8 04 75 9b 84 d2 74 69 8b 85 14 01 00 00 85 c0 75 1b 48 8b 85 28 03 00 00 48 8b 80 98 00 00 00 48 8b 40 20 <8b> 40 18 89 85 14 01 00 00 8b bd 14 01 00 00 81 ff 00 01 00 00 0f [31757.570840] RSP: 0018:ffffc90034f27dc0 EFLAGS: 00010246 [31757.576143] RAX: 0000000000000000 RBX: ffffc90034f27e18 RCX: 0000000000000000 [31757.583389] RDX: 0000000000000001 RSI: ffffc90034f27e18 RDI: ffff88984cf3c100 [31757.590631] RBP: ffff88984714a800 R08: ffff88984714a800 R09: 0000000000000000 [31757.597877] R10: 0000000000000001 R11: 0000000000000000 R12: 00000000fffffffa [31757.605123] R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000000 [31757.612364] FS: 00007fb4c5931180(0000) GS:ffff88afdfa00000(0000) knlGS:0000000000000000 [31757.620571] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [31757.626406] CR2: 0000000000000018 CR3: 000000184b41c003 CR4: 00000000007706e0 [31757.633648] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [31757.640894] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [31757.648139] PKRU: 55555554 [31757.650894] Call Trace: [31757.653385] <TASK> [31757.655524] sock_sendmsg+0x8f/0xa0 [31757.659077] ? sockfd_lookup_light+0x12/0x70 [31757.663416] __sys_sendto+0xfc/0x170 [31757.667051] ? do_sched_setscheduler+0xdb/0x1b0 [31757.671658] __x64_sys_sendto+0x20/0x30 [31757.675557] do_syscall_64+0x38/0x90 [31757.679197] entry_SYSCALL_64_after_hwframe+0x72/0xdc [31757.687969] Code: 8e f6 ff 44 8b 4c 24 2c 4c 8b 44 24 20 41 89 c4 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 3a 44 89 e7 48 89 44 24 08 e8 b5 8e f6 ff 48 [31757.707007] RSP: 002b:00007ffd49c73c70 EFLAGS: 00000293 ORIG_RAX: 000000000000002c [31757.714694] RAX: ffffffffffffffda RBX: 000055a996565380 RCX: 00007fb4c5727c16 [31757.721939] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 [31757.729184] RBP: 0000000000000040 R08: 0000000000000000 R09: 0000000000000000 [31757.736429] R10: 0000000000000040 R11: 0000000000000293 R12: 0000000000000000 [31757.743673] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [31757.754940] </TASK> To fix this, let's make xsk_xmit a function that will be responsible for generic Tx, where RCU is handled accordingly and pull out sanity checks and xs->zc handling. Populate sanity checks to __xsk_sendmsg() and xsk_poll().
INFO
Published Date :
Sept. 15, 2025, 3:15 p.m.
Last Modified :
Sept. 15, 2025, 3:22 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2023-53240
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Update the Linux kernel to the patched version.
- Ensure interface status checks occur before transmit operations.
- Review XSK transmit path logic for race conditions.
- Rebuild and deploy the modified kernel.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2023-53240.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2023-53240 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2023-53240
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2023-53240 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2023-53240 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 15, 2025
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: xsk: check IFF_UP earlier in Tx path Xsk Tx can be triggered via either sendmsg() or poll() syscalls. These two paths share a call to common function xsk_xmit() which has two sanity checks within. A pseudo code example to show the two paths: __xsk_sendmsg() : xsk_poll(): if (unlikely(!xsk_is_bound(xs))) if (unlikely(!xsk_is_bound(xs))) return -ENXIO; return mask; if (unlikely(need_wait)) (...) return -EOPNOTSUPP; xsk_xmit() mark napi id (...) xsk_xmit() xsk_xmit(): if (unlikely(!(xs->dev->flags & IFF_UP))) return -ENETDOWN; if (unlikely(!xs->tx)) return -ENOBUFS; As it can be observed above, in sendmsg() napi id can be marked on interface that was not brought up and this causes a NULL ptr dereference: [31757.505631] BUG: kernel NULL pointer dereference, address: 0000000000000018 [31757.512710] #PF: supervisor read access in kernel mode [31757.517936] #PF: error_code(0x0000) - not-present page [31757.523149] PGD 0 P4D 0 [31757.525726] Oops: 0000 [#1] PREEMPT SMP NOPTI [31757.530154] CPU: 26 PID: 95641 Comm: xdpsock Not tainted 6.2.0-rc5+ #40 [31757.536871] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019 [31757.547457] RIP: 0010:xsk_sendmsg+0xde/0x180 [31757.551799] Code: 00 75 a2 48 8b 00 a8 04 75 9b 84 d2 74 69 8b 85 14 01 00 00 85 c0 75 1b 48 8b 85 28 03 00 00 48 8b 80 98 00 00 00 48 8b 40 20 <8b> 40 18 89 85 14 01 00 00 8b bd 14 01 00 00 81 ff 00 01 00 00 0f [31757.570840] RSP: 0018:ffffc90034f27dc0 EFLAGS: 00010246 [31757.576143] RAX: 0000000000000000 RBX: ffffc90034f27e18 RCX: 0000000000000000 [31757.583389] RDX: 0000000000000001 RSI: ffffc90034f27e18 RDI: ffff88984cf3c100 [31757.590631] RBP: ffff88984714a800 R08: ffff88984714a800 R09: 0000000000000000 [31757.597877] R10: 0000000000000001 R11: 0000000000000000 R12: 00000000fffffffa [31757.605123] R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000000 [31757.612364] FS: 00007fb4c5931180(0000) GS:ffff88afdfa00000(0000) knlGS:0000000000000000 [31757.620571] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [31757.626406] CR2: 0000000000000018 CR3: 000000184b41c003 CR4: 00000000007706e0 [31757.633648] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [31757.640894] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [31757.648139] PKRU: 55555554 [31757.650894] Call Trace: [31757.653385] <TASK> [31757.655524] sock_sendmsg+0x8f/0xa0 [31757.659077] ? sockfd_lookup_light+0x12/0x70 [31757.663416] __sys_sendto+0xfc/0x170 [31757.667051] ? do_sched_setscheduler+0xdb/0x1b0 [31757.671658] __x64_sys_sendto+0x20/0x30 [31757.675557] do_syscall_64+0x38/0x90 [31757.679197] entry_SYSCALL_64_after_hwframe+0x72/0xdc [31757.687969] Code: 8e f6 ff 44 8b 4c 24 2c 4c 8b 44 24 20 41 89 c4 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 3a 44 89 e7 48 89 44 24 08 e8 b5 8e f6 ff 48 [31757.707007] RSP: 002b:00007ffd49c73c70 EFLAGS: 00000293 ORIG_RAX: 000000000000002c [31757.714694] RAX: ffffffffffffffda RBX: 000055a996565380 RCX: 00007fb4c5727c16 [31757.721939] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 [31757.729184] RBP: 0000000000000040 R08: 0000000000000000 R09: 0000000000000000 [31757.736429] R10: 0000000000000040 R11: 0000000000000293 R12: 0000000000000000 [31757.743673] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [31757.754940] </TASK> To fix this, let's make xsk_xmit a function that will be responsible for generic Tx, where RCU is handled accordingly and pull out sanity checks and xs->zc handling. Populate sanity checks to __xsk_sendmsg() and xsk_poll(). Added Reference https://git.kernel.org/stable/c/1596dae2f17ec5c6e8c8f0e3fec78c5ae55c1e0b Added Reference https://git.kernel.org/stable/c/cecc68559cd57fffb2be50685f262b9af2318e16 Added Reference https://git.kernel.org/stable/c/ffe19750e68d0bb21e8110b398346eef20b156a7