Re: [syzbot] [mm?] KASAN: out-of-bounds Read in copy_from_kernel_nofault
From: syzbot
Date: Tue Oct 01 2024 - 00:22:31 EST
syzbot has found a reproducer for the following issue on:
HEAD commit: cea5425829f7 Add linux-next specific files for 20240930
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1250fd07980000
kernel config: https://syzkaller.appspot.com/x/.config?x=41a28720ed564c6a
dashboard link: https://syzkaller.appspot.com/bug?extid=61123a5daeb9f7454599
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=153c439f980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1603f127980000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/566995596f19/disk-cea54258.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e7c506c1c71d/vmlinux-cea54258.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7fcb4468b8c0/bzImage-cea54258.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+61123a5daeb9f7454599@xxxxxxxxxxxxxxxxxxxxxxxxx
==================================================================
BUG: KASAN: out-of-bounds in instrument_memcpy_before include/linux/instrumented.h:163 [inline]
BUG: KASAN: out-of-bounds in copy_from_kernel_nofault+0x7a/0x2f0 mm/maccess.c:35
Read of size 6 at addr fffffffffffffffd by task syz-executor167/5229
CPU: 1 UID: 0 PID: 5229 Comm: syz-executor167 Not tainted 6.12.0-rc1-next-20240930-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
instrument_memcpy_before include/linux/instrumented.h:163 [inline]
copy_from_kernel_nofault+0x7a/0x2f0 mm/maccess.c:35
bpf_probe_read_kernel_common include/linux/bpf.h:2960 [inline]
____bpf_probe_read_kernel kernel/trace/bpf_trace.c:239 [inline]
bpf_probe_read_kernel+0x2a/0x70 kernel/trace/bpf_trace.c:236
bpf_prog_fe7b69aea4fa28bf+0x43/0x45
__bpf_prog_run include/linux/filter.h:701 [inline]
bpf_prog_run_xdp include/net/xdp.h:514 [inline]
bpf_test_run+0x4b1/0xa90 net/bpf/test_run.c:431
bpf_prog_test_run_xdp+0x7da/0x11e0 net/bpf/test_run.c:1319
bpf_prog_test_run+0x2e4/0x360 kernel/bpf/syscall.c:4247
__sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5652
__do_sys_bpf kernel/bpf/syscall.c:5741 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5739 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5739
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50ec364bb9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffed45c06d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f50ec364bb9
RDX: 000000000000003b RSI: 0000000020000240 RDI: 000000000000000a
RBP: 0000000000000000 R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
</TASK>
Memory state around the buggy address:
fffffffffffffe80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffffffffffffff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffffffffffff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 5229 Comm: syz-executor167 Not tainted 6.12.0-rc1-next-20240930-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:kasan_metadata_fetch_row+0x12/0x30 mm/kasan/report_generic.c:186
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 c1 ee 03 48 b8 00 00 00 00 00 fc ff df <48> 8b 0c 06 48 8b 44 06 08 48 89 47 08 48 89 0f c3 cc cc cc cc 66
RSP: 0018:ffffc90002f5f6d8 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: cc1757ac84471d00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90002f5f710
RBP: ffffc90002f5f758 R08: ffffffff8bc0f2d3 R09: 0000000000000020
R10: dffffc0000000000 R11: fffff520005ebee1 R12: ffffc90002f5f710
R13: 0000000000000080 R14: ffffffffffffff80 R15: ffffc90002f5f6f0
FS: 000055558e6ce380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f50ec3db0d0 CR3: 0000000073e8a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
print_memory_metadata mm/kasan/report.c:464 [inline]
print_report+0x4df/0x550 mm/kasan/report.c:489
kasan_report+0x143/0x180 mm/kasan/report.c:601
kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
instrument_memcpy_before include/linux/instrumented.h:163 [inline]
copy_from_kernel_nofault+0x7a/0x2f0 mm/maccess.c:35
bpf_probe_read_kernel_common include/linux/bpf.h:2960 [inline]
____bpf_probe_read_kernel kernel/trace/bpf_trace.c:239 [inline]
bpf_probe_read_kernel+0x2a/0x70 kernel/trace/bpf_trace.c:236
bpf_prog_fe7b69aea4fa28bf+0x43/0x45
__bpf_prog_run include/linux/filter.h:701 [inline]
bpf_prog_run_xdp include/net/xdp.h:514 [inline]
bpf_test_run+0x4b1/0xa90 net/bpf/test_run.c:431
bpf_prog_test_run_xdp+0x7da/0x11e0 net/bpf/test_run.c:1319
bpf_prog_test_run+0x2e4/0x360 kernel/bpf/syscall.c:4247
__sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5652
__do_sys_bpf kernel/bpf/syscall.c:5741 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5739 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5739
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50ec364bb9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffed45c06d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f50ec364bb9
RDX: 000000000000003b RSI: 0000000020000240 RDI: 000000000000000a
RBP: 0000000000000000 R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kasan_metadata_fetch_row+0x12/0x30 mm/kasan/report_generic.c:186
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 c1 ee 03 48 b8 00 00 00 00 00 fc ff df <48> 8b 0c 06 48 8b 44 06 08 48 89 47 08 48 89 0f c3 cc cc cc cc 66
RSP: 0018:ffffc90002f5f6d8 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: cc1757ac84471d00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90002f5f710
RBP: ffffc90002f5f758 R08: ffffffff8bc0f2d3 R09: 0000000000000020
R10: dffffc0000000000 R11: fffff520005ebee1 R12: ffffc90002f5f710
R13: 0000000000000080 R14: ffffffffffffff80 R15: ffffc90002f5f6f0
FS: 000055558e6ce380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f50ec3db0d0 CR3: 0000000073e8a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1)
7: 00
8: 90 nop
9: 90 nop
a: 90 nop
b: 90 nop
c: 90 nop
d: 90 nop
e: 90 nop
f: 90 nop
10: 90 nop
11: 90 nop
12: 90 nop
13: 90 nop
14: 90 nop
15: 90 nop
16: 90 nop
17: 90 nop
18: 66 0f 1f 00 nopw (%rax)
1c: 48 c1 ee 03 shr $0x3,%rsi
20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
27: fc ff df
* 2a: 48 8b 0c 06 mov (%rsi,%rax,1),%rcx <-- trapping instruction
2e: 48 8b 44 06 08 mov 0x8(%rsi,%rax,1),%rax
33: 48 89 47 08 mov %rax,0x8(%rdi)
37: 48 89 0f mov %rcx,(%rdi)
3a: c3 ret
3b: cc int3
3c: cc int3
3d: cc int3
3e: cc int3
3f: 66 data16
---
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