Hello, syzbot found the following issue on: HEAD commit: 61c3426aca2c Add linux-next specific files for 20221102 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=178f72ac880000 kernel config: https://syzkaller.appspot.com/x/.config?x=acb529cc910d907c dashboard link: https://syzkaller.appspot.com/bug?extid=3f6ef1c4586bb6fd1f61 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/cc56d88dd6a3/disk-61c3426a.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/5921b65b080f/vmlinux-61c3426a.xz kernel image: https://storage.googleapis.com/syzbot-assets/39cbd355fedd/bzImage-61c3426a.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+3f6ef1c4586bb6fd1f61@xxxxxxxxxxxxxxxxxxxxxxxxx BUG: unable to handle page fault for address: ffffffffffffffc3 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD bc8f067 P4D bc8f067 PUD bc91067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN CPU: 0 PID: 25127 Comm: syz-executor.4 Not tainted 6.1.0-rc3-next-20221102-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 RIP: 0010:arch_atomic_fetch_sub arch/x86/include/asm/atomic.h:190 [inline] RIP: 0010:atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:177 [inline] RIP: 0010:__refcount_sub_and_test include/linux/refcount.h:272 [inline] RIP: 0010:__refcount_dec_and_test include/linux/refcount.h:315 [inline] RIP: 0010:refcount_dec_and_test include/linux/refcount.h:333 [inline] RIP: 0010:posix_acl_release include/linux/posix_acl.h:57 [inline] RIP: 0010:posix_acl_release include/linux/posix_acl.h:55 [inline] RIP: 0010:ovl_set_or_remove_acl fs/overlayfs/inode.c:624 [inline] RIP: 0010:ovl_set_acl+0x730/0x910 fs/overlayfs/inode.c:685 Code: a3 24 ff 4c 89 ff 49 89 c4 e8 cc 2f 81 fe 4d 85 e4 74 7f e8 52 e9 ac fe be 04 00 00 00 4c 89 e7 bb ff ff ff ff e8 60 7a f9 fe <f0> 41 0f c1 1c 24 bf 01 00 00 00 89 de e8 fe e5 ac fe 83 fb 01 0f RSP: 0018:ffffc9001264fad8 EFLAGS: 00010246 RAX: 0000000000000001 RBX: 00000000ffffffff RCX: ffffffff82cff810 RDX: fffffbfffffffff9 RSI: 0000000000000004 RDI: ffffffffffffffc3 RBP: ffff88804ebd2bc0 R08: 0000000000000001 R09: ffffffffffffffc6 R10: fffffbfffffffff8 R11: 0000000000000001 R12: ffffffffffffffc3 R13: ffff88804e8985f8 R14: 1ffff920024c9f60 R15: ffff88801f580100 FS: 00007fb9df1ff700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffc3 CR3: 000000004dcf4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> set_posix_acl+0x257/0x320 fs/posix_acl.c:957 vfs_remove_acl+0x272/0x630 fs/posix_acl.c:1209 removexattr+0x12a/0x1b0 fs/xattr.c:894 path_removexattr+0x174/0x1a0 fs/xattr.c:910 __do_sys_removexattr fs/xattr.c:924 [inline] __se_sys_removexattr fs/xattr.c:921 [inline] __x64_sys_removexattr+0x55/0x80 fs/xattr.c:921 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fb9dfe8b5a9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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:00007fb9df1ff168 EFLAGS: 00000246 ORIG_RAX: 00000000000000c5 RAX: ffffffffffffffda RBX: 00007fb9dffabf80 RCX: 00007fb9dfe8b5a9 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000020000000 RBP: 00007fb9dfee67b0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdbc7f682f R14: 00007fb9df1ff300 R15: 0000000000022000 </TASK> Modules linked in: CR2: ffffffffffffffc3 ---[ end trace 0000000000000000 ]--- RIP: 0010:arch_atomic_fetch_sub arch/x86/include/asm/atomic.h:190 [inline] RIP: 0010:atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:177 [inline] RIP: 0010:__refcount_sub_and_test include/linux/refcount.h:272 [inline] RIP: 0010:__refcount_dec_and_test include/linux/refcount.h:315 [inline] RIP: 0010:refcount_dec_and_test include/linux/refcount.h:333 [inline] RIP: 0010:posix_acl_release include/linux/posix_acl.h:57 [inline] RIP: 0010:posix_acl_release include/linux/posix_acl.h:55 [inline] RIP: 0010:ovl_set_or_remove_acl fs/overlayfs/inode.c:624 [inline] RIP: 0010:ovl_set_acl+0x730/0x910 fs/overlayfs/inode.c:685 Code: a3 24 ff 4c 89 ff 49 89 c4 e8 cc 2f 81 fe 4d 85 e4 74 7f e8 52 e9 ac fe be 04 00 00 00 4c 89 e7 bb ff ff ff ff e8 60 7a f9 fe <f0> 41 0f c1 1c 24 bf 01 00 00 00 89 de e8 fe e5 ac fe 83 fb 01 0f RSP: 0018:ffffc9001264fad8 EFLAGS: 00010246 RAX: 0000000000000001 RBX: 00000000ffffffff RCX: ffffffff82cff810 RDX: fffffbfffffffff9 RSI: 0000000000000004 RDI: ffffffffffffffc3 RBP: ffff88804ebd2bc0 R08: 0000000000000001 R09: ffffffffffffffc6 R10: fffffbfffffffff8 R11: 0000000000000001 R12: ffffffffffffffc3 R13: ffff88804e8985f8 R14: 1ffff920024c9f60 R15: ffff88801f580100 FS: 00007fb9df1ff700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffc3 CR3: 000000004dcf4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: a3 24 ff 4c 89 ff 49 movabs %eax,0xc48949ff894cff24 7: 89 c4 9: e8 cc 2f 81 fe callq 0xfe812fda e: 4d 85 e4 test %r12,%r12 11: 74 7f je 0x92 13: e8 52 e9 ac fe callq 0xfeace96a 18: be 04 00 00 00 mov $0x4,%esi 1d: 4c 89 e7 mov %r12,%rdi 20: bb ff ff ff ff mov $0xffffffff,%ebx 25: e8 60 7a f9 fe callq 0xfef97a8a * 2a: f0 41 0f c1 1c 24 lock xadd %ebx,(%r12) <-- trapping instruction 30: bf 01 00 00 00 mov $0x1,%edi 35: 89 de mov %ebx,%esi 37: e8 fe e5 ac fe callq 0xfeace63a 3c: 83 fb 01 cmp $0x1,%ebx 3f: 0f .byte 0xf --- This report is generated by a bot. 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