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BUG: bad usercopy in tcp_sendmsg_locked (2)

Status: closed as invalid on 2023/08/31 13:30
Subsystems: hardening mm
[Documentation on labels]
First crash: 545d, last: 545d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: bad usercopy in tcp_sendmsg_locked hardening mm 1 751d 751d 0/28 closed as invalid on 2023/02/13 10:50

Sample crash report:
usercopy: Kernel memory overwrite attempt detected to SLUB object 'kmalloc-4k' (offset 0, size 32768)!
------------[ cut here ]------------
kernel BUG at mm/usercopy.c:102!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 5005 Comm: sshd Not tainted 6.5.0-rc4-syzkaller-00009-g4b954598a47b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
RIP: 0010:usercopy_abort+0x83/0x90 mm/usercopy.c:102
Code: ce 49 89 ce 48 c7 c3 80 e5 16 8b 48 0f 44 de 48 c7 c7 20 e4 16 8b 4c 89 de 48 89 c1 41 52 41 56 53 e8 61 8d c8 08 48 83 c4 18 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 55 41 57 41 56
RSP: 0018:ffffc9000398f7f0 EFLAGS: 00010296
RAX: 0000000000000066 RBX: ffffffff8b16e580 RCX: 1c99b543c0edd900
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff816efc8c R09: 1ffff92000731eb0
R10: dffffc0000000000 R11: fffff52000731eb1 R12: 1ffffd40001c5f01
R13: 0000000000008000 R14: 0000000000000000 R15: 0000000000008000
FS:  00007f2b84d38800(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2279fd4cc0 CR3: 000000002d5a6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __check_heap_object+0xad/0x100 mm/slub.c:4776
 check_heap_object mm/usercopy.c:196 [inline]
 __check_object_size+0x2d8/0xa40 mm/usercopy.c:251
 check_object_size include/linux/thread_info.h:215 [inline]
 check_copy_size include/linux/thread_info.h:251 [inline]
 copy_from_iter include/linux/uio.h:201 [inline]
 copy_from_iter_full include/linux/uio.h:209 [inline]
 skb_do_copy_data_nocache include/net/sock.h:2253 [inline]
 skb_copy_to_page_nocache include/net/sock.h:2279 [inline]
 tcp_sendmsg_locked+0x16eb/0x5010 net/ipv4/tcp.c:1198
 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1333
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 sock_write_iter+0x39a/0x520 net/socket.c:1129
 call_write_iter include/linux/fs.h:1871 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x782/0xaf0 fs/read_write.c:584
 ksys_write+0x1a0/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f2b84916bf2
Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffc6372cac8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000008024 RCX: 00007f2b84916bf2
RDX: 0000000000008024 RSI: 000055ea364545b0 RDI: 0000000000000004
RBP: 000055ea36434220 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000055ea34ddeaa4
R13: 000000000000012f R14: 000055ea34ddf3e8 R15: 00007ffc6372cb38
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:usercopy_abort+0x83/0x90 mm/usercopy.c:102
Code: ce 49 89 ce 48 c7 c3 80 e5 16 8b 48 0f 44 de 48 c7 c7 20 e4 16 8b 4c 89 de 48 89 c1 41 52 41 56 53 e8 61 8d c8 08 48 83 c4 18 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 55 41 57 41 56
RSP: 0018:ffffc9000398f7f0 EFLAGS: 00010296
RAX: 0000000000000066 RBX: ffffffff8b16e580 RCX: 1c99b543c0edd900
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff816efc8c R09: 1ffff92000731eb0
R10: dffffc0000000000 R11: fffff52000731eb1 R12: 1ffffd40001c5f01
R13: 0000000000008000 R14: 0000000000000000 R15: 0000000000008000
FS:  00007f2b84d38800(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555a78938 CR3: 000000002d5a6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/03 02:32 upstream 4b954598a47b b178af49 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs BUG: bad usercopy in tcp_sendmsg_locked
* Struck through repros no longer work on HEAD.