[syzbot] [hfs?] memory leak in hfsplus_init_fs_context

syzbot
2025-12-05T05:38:24Z

Hello,

syzbot found the following issue on:

HEAD commit: e69c7c175115 Merge tag 'timers_urgent_for_v6.18_rc8' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=116ffcb4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f30cc590c4f6da44
dashboard link: https://syzkaller.appspot.com/bug?extid=99f6ed51479b86ac4c41
compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10eef912580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1534c192580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e1758d9b5b79/disk-e69c7c17.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/772ec0d0a545/vmlinux-e69c7c17.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d905337ef02b/bzImage-e69c7c17.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/65bc76439748/mount_4.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+99f6ed51479b86ac4c41@syzkaller.appspotmail.com

BUG: memory leak
unreferenced object 0xffff8881287f8a00 (size 512):
comm "syz.0.17", pid 6072, jiffies 4294944858
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc aaf4239b):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4983 [inline]
slab_alloc_node mm/slub.c:5288 [inline]
__kmalloc_cache_noprof+0x3a6/0x5b0 mm/slub.c:5766
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
hfsplus_init_fs_context+0x26/0x90 fs/hfsplus/super.c:678
alloc_fs_context+0x214/0x430 fs/fs_context.c:315
do_new_mount fs/namespace.c:3698 [inline]
path_mount+0x93c/0x12e0 fs/namespace.c:4028
do_mount fs/namespace.c:4041 [inline]
__do_sys_mount fs/namespace.c:4229 [inline]
__se_sys_mount fs/namespace.c:4206 [inline]
__x64_sys_mount+0x1a2/0x1e0 fs/namespace.c:4206
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object 0xffff8881287f9a00 (size 512):
comm "syz.0.18", pid 6078, jiffies 4294944862
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc aaf4239b):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4983 [inline]
slab_alloc_node mm/slub.c:5288 [inline]
__kmalloc_cache_noprof+0x3a6/0x5b0 mm/slub.c:5766
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
hfsplus_init_fs_context+0x26/0x90 fs/hfsplus/super.c:678
alloc_fs_context+0x214/0x430 fs/fs_context.c:315
do_new_mount fs/namespace.c:3698 [inline]
path_mount+0x93c/0x12e0 fs/namespace.c:4028
do_mount fs/namespace.c:4041 [inline]
__do_sys_mount fs/namespace.c:4229 [inline]
__se_sys_mount fs/namespace.c:4206 [inline]
__x64_sys_mount+0x1a2/0x1e0 fs/namespace.c:4206
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object 0xffff8881287f9c00 (size 512):
comm "syz.0.19", pid 6079, jiffies 4294944864
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc aaf4239b):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4983 [inline]
slab_alloc_node mm/slub.c:5288 [inline]
__kmalloc_cache_noprof+0x3a6/0x5b0 mm/slub.c:5766
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
hfsplus_init_fs_context+0x26/0x90 fs/hfsplus/super.c:678
alloc_fs_context+0x214/0x430 fs/fs_context.c:315
do_new_mount fs/namespace.c:3698 [inline]
path_mount+0x93c/0x12e0 fs/namespace.c:4028
do_mount fs/namespace.c:4041 [inline]
__do_sys_mount fs/namespace.c:4229 [inline]
__se_sys_mount fs/namespace.c:4206 [inline]
__x64_sys_mount+0x1a2/0x1e0 fs/namespace.c:4206
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF

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