Dear Maintainers, When using our customized Syzkaller to fuzz the latest Linux kernel, the following crash (14th)was triggered. HEAD commit: 6537cfb395f352782918d8ee7b7f10ba2cc3cbf2 git tree: upstream Output:https://github.com/pghk13/Kernel-Bug/blob/main/1220_6.13rc_KASAN/2.%E5%9B%9E%E5%BD%92-11/14-KASAN_%20slab-out-of-bounds%20Read%20in%20hfsplus_bnode_read/14call_trace.txt Kernel config:https://github.com/pghk13/Kernel-Bug/blob/main/config.txt C reproducer:https://github.com/pghk13/Kernel-Bug/blob/main/1220_6.13rc_KASAN/2.%E5%9B%9E%E5%BD%92-11/14-KASAN_%20slab-out-of-bounds%20Read%20in%20hfsplus_bnode_read/14repro.c Syzlang reproducer: https://github.com/pghk13/Kernel-Bug/blob/main/1220_6.13rc_KASAN/2.%E5%9B%9E%E5%BD%92-11/14-KASAN_%20slab-out-of-bounds%20Read%20in%20hfsplus_bnode_read/14repro.txt Our reproducer uses mounts a constructed filesystem image. Problems can arise in hfs_bnode_read functions. node->page[pagenum] causes out-of-bounds reads when accessing memory that exceeds the range of the node's allotted page array. In particular, when a hfs_bnode_dump function reads with this function, an offset or length that exceeds the actual size of the node may be passed in. In the hfsplus_bnode_dump (inferred from the error call stack), when traversing the records in the B-tree node, an incorrect offset calculation may have been used, resulting in data being read out of the allocated memory. Consider adding stricter bounds checking to the hfs_bnode_read function. We have reproduced this issue several times on 6.15-rc1 again. If you fix this issue, please add the following tag to the commit: Reported-by: Kun Hu <huk23@xxxxxxxxxxxxxx>, Jiaji Qin <jjtan24@xxxxxxxxxxxxxx>, Shuoran Bai <baishuoran@xxxxxxxxxxxx> ================================================================== BUG: KASAN: slab-out-of-bounds in hfsplus_bnode_read+0x268/0x290 Read of size 8 at addr ffff8880439aefc0 by task syz-executor201/9472 CPU: 1 UID: 0 PID: 9472 Comm: syz-executor201 Not tainted 6.15.0-rc1 #1 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x116/0x1b0 print_report+0xc1/0x630 kasan_report+0x96/0xd0 hfsplus_bnode_read+0x268/0x290 hfsplus_bnode_dump+0x2c6/0x3a0 hfsplus_brec_remove+0x3e4/0x4f0 __hfsplus_delete_attr+0x28e/0x3a0 hfsplus_delete_all_attrs+0x13e/0x270 hfsplus_delete_cat+0x67f/0xb60 hfsplus_unlink+0x1ce/0x7d0 vfs_unlink+0x30e/0x9f0 do_unlinkat+0x4d9/0x6a0 __x64_sys_unlink+0x40/0x50 do_syscall_64+0xcf/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcd9a901f5b Code: 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 57 00 00 00 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:00007ffeefb025d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fcd9a901f5b RDX: 00007ffeefb02600 RSI: 00007ffeefb02600 RDI: 00007ffeefb02690 RBP: 00007ffeefb02690 R08: 0000000000000001 R09: 00007ffeefb02460 R10: 00000000fffffffb R11: 0000000000000206 R12: 00007ffeefb03790 R13: 00005555641a1bb0 R14: 00007ffeefb025f8 R15: 0000000000000001 </TASK> Allocated by task 9472: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0xaa/0xb0 __kmalloc_noprof+0x214/0x600 __hfs_bnode_create+0x105/0x750 hfsplus_bnode_find+0x1e5/0xb70 hfsplus_brec_find+0x2b2/0x530 hfsplus_find_attr+0x12e/0x170 hfsplus_delete_all_attrs+0x16f/0x270 hfsplus_delete_cat+0x67f/0xb60 hfsplus_rmdir+0x106/0x1b0 vfs_rmdir+0x2ae/0x680 do_rmdir+0x2d1/0x390 __x64_sys_rmdir+0x40/0x50 do_syscall_64+0xcf/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880439aef00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 40 bytes to the right of allocated 152-byte region [ffff8880439aef00, ffff8880439aef98) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x439ae anon flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000000 ffff88801b4423c0 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 46334294792, free_ts 46209226995 prep_new_page+0x1b0/0x1e0 get_page_from_freelist+0x1649/0x30f0 __alloc_frozen_pages_noprof+0x2fd/0x6d0 alloc_pages_mpol+0x209/0x550 new_slab+0x24b/0x340 ___slab_alloc+0xf0c/0x17c0 __slab_alloc.isra.0+0x56/0xb0 __kmalloc_cache_noprof+0x291/0x4b0 call_usermodehelper_setup+0xb2/0x360 kobject_uevent_env+0xf82/0x16c0 driver_bound+0x15b/0x220 really_probe+0x56e/0x990 __driver_probe_device+0x1df/0x450 driver_probe_device+0x4c/0x1a0 __device_attach_driver+0x1e4/0x2d0 bus_for_each_drv+0x14b/0x1d0 page last free pid 1277 tgid 1277 stack trace: __free_frozen_pages+0x7cd/0x1320 __put_partials+0x14c/0x170 qlist_free_all+0x50/0x130 kasan_quarantine_reduce+0x168/0x1c0 __kasan_slab_alloc+0x67/0x90 __kmalloc_cache_noprof+0x169/0x4b0 usb_control_msg+0xbc/0x4a0 hub_ext_port_status+0x12c/0x6b0 hub_activate+0x9f6/0x1aa0 process_scheduled_works+0x5de/0x1bd0 worker_thread+0x5a9/0xd10 kthread+0x447/0x8a0 ret_from_fork+0x48/0x80 ret_from_fork_asm+0x1a/0x30 Memory state around the buggy address: ffff8880439aee80: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880439aef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880439aef80: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880439af000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880439af080: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ================================================================== thanks, Kun Hu
