mirror of
https://git.proxmox.com/git/mirror_ubuntu-kernels.git
synced 2025-12-09 09:48:57 +00:00
Syzbot reported the following splat:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 UID: 0 PID: 5836 Comm: sshd Not tainted 6.13.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
RIP: 0010:_compound_head include/linux/page-flags.h:242 [inline]
RIP: 0010:put_page+0x23/0x260 include/linux/mm.h:1552
Code: 90 90 90 90 90 90 90 55 41 57 41 56 53 49 89 fe 48 bd 00 00 00 00 00 fc ff df e8 f8 5e 12 f8 49 8d 5e 08 48 89 d8 48 c1 e8 03 <80> 3c 28 00 74 08 48 89 df e8 8f c7 78 f8 48 8b 1b 48 89 de 48 83
RSP: 0000:ffffc90003916c90 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000008 RCX: ffff888030458000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff898ca81d R09: 1ffff110054414ac
R10: dffffc0000000000 R11: ffffed10054414ad R12: 0000000000000007
R13: ffff88802a20a542 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f34f496e800(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9d6ec9ec28 CR3: 000000004d260000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
skb_page_unref include/linux/skbuff_ref.h:43 [inline]
__skb_frag_unref include/linux/skbuff_ref.h:56 [inline]
skb_release_data+0x483/0x8a0 net/core/skbuff.c:1119
skb_release_all net/core/skbuff.c:1190 [inline]
__kfree_skb+0x55/0x70 net/core/skbuff.c:1204
tcp_clean_rtx_queue net/ipv4/tcp_input.c:3436 [inline]
tcp_ack+0x2442/0x6bc0 net/ipv4/tcp_input.c:4032
tcp_rcv_state_process+0x8eb/0x44e0 net/ipv4/tcp_input.c:6805
tcp_v4_do_rcv+0x77d/0xc70 net/ipv4/tcp_ipv4.c:1939
tcp_v4_rcv+0x2dc0/0x37f0 net/ipv4/tcp_ipv4.c:2351
ip_protocol_deliver_rcu+0x22e/0x440 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233
NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
__netif_receive_skb_one_core net/core/dev.c:5672 [inline]
__netif_receive_skb+0x2bf/0x650 net/core/dev.c:5785
process_backlog+0x662/0x15b0 net/core/dev.c:6117
__napi_poll+0xcb/0x490 net/core/dev.c:6883
napi_poll net/core/dev.c:6952 [inline]
net_rx_action+0x89b/0x1240 net/core/dev.c:7074
handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
__do_softirq kernel/softirq.c:595 [inline]
invoke_softirq kernel/softirq.c:435 [inline]
__irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0x57/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0033:0x7f34f4519ad5
Code: 85 d2 74 0d 0f 10 02 48 8d 54 24 20 0f 11 44 24 20 64 8b 04 25 18 00 00 00 85 c0 75 27 41 b8 08 00 00 00 b8 0f 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 75 48 8b 15 24 73 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffec5b32ce0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 00000000000668a0 RCX: 00007f34f4519ad5
RDX: 00007ffec5b32d00 RSI: 0000000000000004 RDI: 0000564f4bc6cae0
RBP: 0000564f4bc6b5a0 R08: 0000000000000008 R09: 0000000000000000
R10: 00007ffec5b32de8 R11: 0000000000000246 R12: 0000564f48ea8aa4
R13: 0000000000000001 R14: 0000564f48ea93e8 R15: 00007ffec5b32d68
</TASK>
Eric noted a probable shinfo->nr_frags corruption, which indeed
occurs.
The root cause is a buggy MPTCP option len computation in some
circumstances: the ADD_ADDR option should be mutually exclusive
with DSS since the blamed commit.
Still, mptcp_established_options_add_addr() tries to set the
relevant info in mptcp_out_options, if the remaining space is
large enough even when DSS is present.
Since the ADD_ADDR infos and the DSS share the same union
fields, adding first corrupts the latter. In the worst-case
scenario, such corruption increases the DSS binary layout,
exceeding the computed length and possibly overwriting the
skb shared info.
Address the issue by enforcing mutual exclusion in
mptcp_established_options_add_addr(), too.
Cc: stable@vger.kernel.org
Reported-by: syzbot+38a095a81f30d82884c1@syzkaller.appspotmail.com
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/538
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.