Re: [syzbot] [hfs?] KASAN: wild-memory-access Read in hfsplus_bnode_dump

From: syzbot
Date: Thu May 25 2023 - 16:04:01 EST

syzbot has found a reproducer for the following issue on:

HEAD commit: 933174ae28ba Merge tag 'spi-fix-v6.4-rc3' of git://git.ker..
git tree: upstream
kernel config:
dashboard link:
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:
C reproducer:

Downloadable assets:
disk image:
kernel image:
mounted in repro:

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f687659f3c2acfa34201@xxxxxxxxxxxxxxxxxxxxxxxxx

memfd_create() without MFD_EXEC nor MFD_NOEXEC_SEAL, pid=4993 'syz-executor106'
loop0: detected capacity change from 0 to 1024
hfsplus: request for non-existent node 32768 in B*Tree
hfsplus: request for non-existent node 32768 in B*Tree
BUG: KASAN: wild-memory-access in memcpy_from_page include/linux/highmem.h:417 [inline]
BUG: KASAN: wild-memory-access in hfsplus_bnode_read fs/hfsplus/bnode.c:32 [inline]
BUG: KASAN: wild-memory-access in hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:45 [inline]
BUG: KASAN: wild-memory-access in hfsplus_bnode_dump+0x403/0xba0 fs/hfsplus/bnode.c:305
Read of size 2 at addr 000508800000103e by task syz-executor106/4993

CPU: 0 PID: 4993 Comm: syz-executor106 Not tainted 6.4.0-rc3-syzkaller-00032-g933174ae28ba #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/16/2023
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
print_report+0xe6/0x540 mm/kasan/report.c:465
kasan_report+0x176/0x1b0 mm/kasan/report.c:572
kasan_check_range+0x283/0x290 mm/kasan/generic.c:187
__asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
memcpy_from_page include/linux/highmem.h:417 [inline]
hfsplus_bnode_read fs/hfsplus/bnode.c:32 [inline]
hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:45 [inline]
hfsplus_bnode_dump+0x403/0xba0 fs/hfsplus/bnode.c:305
hfsplus_brec_remove+0x42c/0x4f0 fs/hfsplus/brec.c:229
__hfsplus_delete_attr+0x275/0x450 fs/hfsplus/attributes.c:299
hfsplus_delete_all_attrs+0x26b/0x3c0 fs/hfsplus/attributes.c:378
hfsplus_delete_cat+0xb87/0xfc0 fs/hfsplus/catalog.c:425
hfsplus_unlink+0x363/0x7f0 fs/hfsplus/dir.c:385
vfs_unlink+0x35d/0x5f0 fs/namei.c:4327
do_unlinkat+0x4a7/0x950 fs/namei.c:4393
__do_sys_unlink fs/namei.c:4441 [inline]
__se_sys_unlink fs/namei.c:4439 [inline]
__x64_sys_unlink+0x49/0x50 fs/namei.c:4439
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
RIP: 0033:0x7f5196975789
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc9b401ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5196975789
RDX: 00007f5196933e03 RSI: 0000000000000000 RDI: 0000000020000140
RBP: 00007f5196935020 R08: 0000000000000640 R09: 0000000000000000
R10: 00007ffc9b401bb0 R11: 0000000000000246 R12: 00007f51969350b0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
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