Re: [PATCH] fs/super: fix memory leak of s_fs_info on setup_bdev_super failure

[kernel test robot <oliver.sang@intel.com>]

Hello,

kernel test robot noticed "Oops:general_protection_fault,probably_for_non-canonical_address#:#[##]SMP_KASAN_PTI" on:

commit: 45f3d9974e382495db777e0290a32ba0cd6f454b ("[PATCH] fs/super: fix memory leak of s_fs_info on setup_bdev_super failure")
url: https://github.com/intel-lab-lkp/linux/commits/Mehdi-Ben-Hadj-Khelifa/fs-super-fix-memory-leak-of-s_fs_info-on-setup_bdev_super-failure/20251115-001149
base: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git 6da43bbeb6918164f7287269881a5f861ae09d7e
patch link: https://lore.kernel.org/all/20251114165255.101361-1-mehdi.benhadjkhelifa@gmail.com/
patch subject: [PATCH] fs/super: fix memory leak of s_fs_info on setup_bdev_super failure

in testcase: nvml
version: nvml-x86_64-4cbe1fd37-1_20251013
with following parameters:

	test: non-pmem
	group: util



config: x86_64-rhel-9.4-func
compiler: gcc-14
test machine: 8 threads 1 sockets Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz (Haswell) with 8G memory

(please refer to attached dmesg/kmsg for entire log/backtrace)



If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <oliver.sang@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202511262155.f86d1a5f-lkp@intel.com


[  164.783048][T42994] EXT4-fs (loop0): VFS: Can't find ext4 filesystem
[  164.792057][T42994] EXT4-fs (loop0): VFS: Can't find ext4 filesystem
[  164.798663][T42994] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
[  164.810433][T42994] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
[  164.818722][T42994] CPU: 3 UID: 0 PID: 42994 Comm: mount Tainted: G S                  6.18.0-rc5-00215-g45f3d9974e38 #1 PREEMPT(voluntary)
[  164.831362][T42994] Tainted: [S]=CPU_OUT_OF_SPEC
[  164.835992][T42994] Hardware name: Dell Inc. OptiPlex 9020/0DNKMN, BIOS A05 12/05/2013
[  164.843927][T42994] RIP: 0010:fuse_kill_sb_blk (kbuild/src/consumer/fs/fuse/inode.c:2126 kbuild/src/consumer/fs/fuse/inode.c:2153) fuse
[  164.850056][T42994] Code: 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 6a 48 8b 9b 90 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 75 60 48 8b 3b e8 ec f8 ff ff 48 85 db 74 1a 48 83 c4
All code
========
   0:	00 00                	add    %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	00 fc                	add    %bh,%ah
   6:	ff                   	lcall  (bad)
   7:	df 48 c1             	fisttps -0x3f(%rax)
   a:	ea                   	(bad)
   b:	03 80 3c 02 00 75    	add    0x7500023c(%rax),%eax
  11:	6a 48                	push   $0x48
  13:	8b 9b 90 03 00 00    	mov    0x390(%rbx),%ebx
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df 
  23:	48 89 da             	mov    %rbx,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
  2a:*	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)		<-- trapping instruction
  2e:	75 60                	jne    0x90
  30:	48 8b 3b             	mov    (%rbx),%rdi
  33:	e8 ec f8 ff ff       	call   0xfffffffffffff924
  38:	48 85 db             	test   %rbx,%rbx
  3b:	74 1a                	je     0x57
  3d:	48                   	rex.W
  3e:	83                   	.byte 0x83
  3f:	c4                   	.byte 0xc4

Code starting with the faulting instruction
===========================================
   0:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   4:	75 60                	jne    0x66
   6:	48 8b 3b             	mov    (%rbx),%rdi
   9:	e8 ec f8 ff ff       	call   0xfffffffffffff8fa
   e:	48 85 db             	test   %rbx,%rbx
  11:	74 1a                	je     0x2d
  13:	48                   	rex.W
  14:	83                   	.byte 0x83
  15:	c4                   	.byte 0xc4
[  164.869568][T42994] RSP: 0018:ffffc900022dfbc8 EFLAGS: 00010246
[  164.875504][T42994] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff81580d23
[  164.883352][T42994] RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8882004c8014
[  164.891213][T42994] RBP: ffffffffc020dba0 R08: 0000000000000001 R09: ffffed1040099000
[  164.899068][T42994] R10: ffff8882004c8007 R11: ffffffff81e792d8 R12: 00000000ffffffea
[  164.906921][T42994] R13: ffff88810dc18390 R14: ffffffffc0446ab0 R15: 00000000ffffffea
[  164.914770][T42994] FS:  00007ff3e6309840(0000) GS:ffff88821483e000(0000) knlGS:0000000000000000
[  164.923579][T42994] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  164.930038][T42994] CR2: 000055c480d92328 CR3: 00000001ec872005 CR4: 00000000001726f0
[  164.937888][T42994] Call Trace:
[  164.941038][T42994]  <TASK>
[  164.943841][T42994]  ? __pfx_fuse_fill_super (kbuild/src/consumer/fs/fuse/inode.c:1939) fuse
[  164.949619][T42994]  deactivate_locked_super (kbuild/src/consumer/fs/super.c:434 kbuild/src/consumer/fs/super.c:475)
[  164.954861][T42994]  get_tree_bdev_flags (kbuild/src/consumer/fs/super.c:1699)
[  164.959839][T42994]  ? __pfx_get_tree_bdev_flags (kbuild/src/consumer/fs/super.c:1662)


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20251126/202511262155.f86d1a5f-lkp@intel.com



-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki