[syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    021533194476 Kconfig: Disable -Wstringop-overflow for GCC ..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1674acffe80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f204e0b6490f4419
dashboard link: https://syzkaller.appspot.com/bug?extid=c244f4a09ca85dd2ebc1
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3c5d4d2f86e3/disk-02153319.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b16ab56fc47a/vmlinux-02153319.xz
kernel image: https://storage.googleapis.com/syzbot-assets/07a8e67be96d/bzImage-02153319.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c244f4a09ca85dd2ebc1@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:686 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock+0x6bc/0xd70 kernel/locking/mutex.c:752
Read of size 8 at addr ffff88807bc26108 by task jfsCommit/109

CPU: 0 PID: 109 Comm: jfsCommit Not tainted 6.8.0-rc2-syzkaller-00199-g021533194476 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x167/0x540 mm/kasan/report.c:488
 kasan_report+0x142/0x180 mm/kasan/report.c:601
 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline]
 __mutex_lock_common kernel/locking/mutex.c:686 [inline]
 __mutex_lock+0x6bc/0xd70 kernel/locking/mutex.c:752
 jfs_syncpt+0x26/0xa0 fs/jfs/jfs_logmgr.c:1039
 txEnd+0x30f/0x560 fs/jfs/jfs_txnmgr.c:549
 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline]
 jfs_lazycommit+0x619/0xb70 fs/jfs/jfs_txnmgr.c:2733
 kthread+0x2ef/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242
 </TASK>

Allocated by task 9990:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:372 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:389
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 kmalloc_trace+0x1d6/0x360 mm/slub.c:4012
 kmalloc include/linux/slab.h:590 [inline]
 kzalloc include/linux/slab.h:711 [inline]
 open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline]
 lmLogOpen+0x335/0x1050 fs/jfs/jfs_logmgr.c:1069
 jfs_mount_rw+0xf1/0x6a0 fs/jfs/jfs_mount.c:257
 jfs_fill_super+0x681/0xc50 fs/jfs/super.c:565
 mount_bdev+0x20a/0x2d0 fs/super.c:1663
 legacy_get_tree+0xee/0x190 fs/fs_context.c:662
 vfs_get_tree+0x90/0x2a0 fs/super.c:1784
 do_new_mount+0x2be/0xb40 fs/namespace.c:3352
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
 do_syscall_64+0xf9/0x240
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

Freed by task 9990:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x4e/0x60 mm/kasan/generic.c:640
 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:241
 __kasan_slab_free+0x34/0x70 mm/kasan/common.c:257
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2121 [inline]
 slab_free mm/slub.c:4299 [inline]
 kfree+0x14a/0x380 mm/slub.c:4409
 lmLogClose+0x2a1/0x530
 jfs_remount+0x435/0x6b0 fs/jfs/super.c:466
 reconfigure_super+0x445/0x880 fs/super.c:1076
 do_remount fs/namespace.c:2892 [inline]
 path_mount+0xc28/0xfa0 fs/namespace.c:3671
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
 do_syscall_64+0xf9/0x240
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

The buggy address belongs to the object at ffff88807bc26000
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 264 bytes inside of
 freed 1024-byte region [ffff88807bc26000, ffff88807bc26400)

The buggy address belongs to the physical page:
page:ffffea0001ef0800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7bc20
head:ffffea0001ef0800 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888014c41dc0 ffffea0001e53000 dead000000000003
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5137, tgid 5137 (kworker/0:5), ts 122851474325, free_ts 122848490685
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533
 prep_new_page mm/page_alloc.c:1540 [inline]
 get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311
 __alloc_pages+0x255/0x680 mm/page_alloc.c:4567
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page+0x5f/0x160 mm/slub.c:2190
 allocate_slab mm/slub.c:2354 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2407
 ___slab_alloc+0xd17/0x13e0 mm/slub.c:3540
 __slab_alloc mm/slub.c:3625 [inline]
 __slab_alloc_node mm/slub.c:3678 [inline]
 slab_alloc_node mm/slub.c:3850 [inline]
 __do_kmalloc_node mm/slub.c:3980 [inline]
 __kmalloc_node_track_caller+0x2d1/0x4e0 mm/slub.c:4001
 kmalloc_reserve+0xf3/0x260 net/core/skbuff.c:582
 __alloc_skb+0x1b1/0x420 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1296 [inline]
 nlmsg_new include/net/netlink.h:1010 [inline]
 inet6_rt_notify+0xdf/0x290 net/ipv6/route.c:6171
 fib6_add_rt2node net/ipv6/ip6_fib.c:1251 [inline]
 fib6_add+0x1dc4/0x3d50 net/ipv6/ip6_fib.c:1477
 __ip6_ins_rt net/ipv6/route.c:1303 [inline]
 ip6_route_add+0x88/0x120 net/ipv6/route.c:3847
 addrconf_add_mroute net/ipv6/addrconf.c:2501 [inline]
 addrconf_add_dev+0x35b/0x540 net/ipv6/addrconf.c:2519
 addrconf_dev_config net/ipv6/addrconf.c:3423 [inline]
 addrconf_init_auto_addrs+0x85f/0xeb0 net/ipv6/addrconf.c:3510
 addrconf_notify+0xaff/0x1020 net/ipv6/addrconf.c:3683
 notifier_call_chain+0x18f/0x3b0 kernel/notifier.c:93
page last free pid 5138 tgid 5138 stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1140 [inline]
 free_unref_page_prepare+0x95d/0xa80 mm/page_alloc.c:2346
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486
 discard_slab mm/slub.c:2453 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:2922
 put_cpu_partial+0x17b/0x250 mm/slub.c:2997
 __slab_free+0x302/0x410 mm/slub.c:4166
 qlink_free mm/kasan/quarantine.c:160 [inline]
 qlist_free_all+0x6d/0xd0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:324
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3813 [inline]
 slab_alloc_node mm/slub.c:3860 [inline]
 kmem_cache_alloc_node+0x18f/0x380 mm/slub.c:3903
 __alloc_skb+0x181/0x420 net/core/skbuff.c:641
 alloc_skb include/linux/skbuff.h:1296 [inline]
 alloc_skb_with_frags+0xc3/0x780 net/core/skbuff.c:6394
 sock_alloc_send_pskb+0x919/0xa60 net/core/sock.c:2784
 sock_alloc_send_skb include/net/sock.h:1855 [inline]
 mld_newpack+0x1c3/0xa90 net/ipv6/mcast.c:1746
 add_grhead net/ipv6/mcast.c:1849 [inline]
 add_grec+0x1492/0x19a0 net/ipv6/mcast.c:1987
 mld_send_initial_cr+0xed/0x240 net/ipv6/mcast.c:2233
 mld_dad_work+0x45/0x270 net/ipv6/mcast.c:2259

Memory state around the buggy address:
 ffff88807bc26000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807bc26080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807bc26100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88807bc26180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807bc26200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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Re: [syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    ced590523156 Merge tag 'driver-core-6.8-rc5' of git://git...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15ee1872180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=64757d4899f04e1b
dashboard link: https://syzkaller.appspot.com/bug?extid=c244f4a09ca85dd2ebc1
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=118f3658180000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=119df694180000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-ced59052.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/268f9dfca97a/vmlinux-ced59052.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d95591974e31/bzImage-ced59052.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/c890e5e09b22/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c244f4a09ca85dd2ebc1@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:686 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock+0x8f4/0x9d0 kernel/locking/mutex.c:752
Read of size 8 at addr ffff8880272d2908 by task jfsCommit/131

CPU: 3 PID: 131 Comm: jfsCommit Not tainted 6.8.0-rc4-syzkaller-00388-gced590523156 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc4/0x620 mm/kasan/report.c:488
 kasan_report+0xda/0x110 mm/kasan/report.c:601
 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline]
 __mutex_lock_common kernel/locking/mutex.c:686 [inline]
 __mutex_lock+0x8f4/0x9d0 kernel/locking/mutex.c:752
 jfs_syncpt+0x2a/0xa0 fs/jfs/jfs_logmgr.c:1039
 txEnd+0x30d/0x5a0 fs/jfs/jfs_txnmgr.c:549
 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline]
 jfs_lazycommit+0x77d/0xb20 fs/jfs/jfs_txnmgr.c:2733
 kthread+0x2c6/0x3b0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242
 </TASK>

Allocated by task 5178:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:372 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:389
 kmalloc include/linux/slab.h:590 [inline]
 kzalloc include/linux/slab.h:711 [inline]
 open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline]
 lmLogOpen+0x571/0x1410 fs/jfs/jfs_logmgr.c:1069
 jfs_mount_rw+0x2ea/0x700 fs/jfs/jfs_mount.c:257
 jfs_fill_super+0x9d6/0xd20 fs/jfs/super.c:565
 mount_bdev+0x1e3/0x2d0 fs/super.c:1663
 legacy_get_tree+0x109/0x220 fs/fs_context.c:662
 vfs_get_tree+0x8f/0x380 fs/super.c:1784
 do_new_mount fs/namespace.c:3352 [inline]
 path_mount+0x14ea/0x1f20 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount fs/namespace.c:3875 [inline]
 __x64_sys_mount+0x297/0x320 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

Freed by task 5177:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640
 poison_slab_object mm/kasan/common.c:241 [inline]
 __kasan_slab_free+0x121/0x1c0 mm/kasan/common.c:257
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2121 [inline]
 slab_free mm/slub.c:4299 [inline]
 kfree+0x124/0x370 mm/slub.c:4409
 lmLogClose+0x585/0x710 fs/jfs/jfs_logmgr.c:1461
 jfs_umount+0x2f0/0x440 fs/jfs/jfs_umount.c:114
 jfs_put_super+0x88/0x1d0 fs/jfs/super.c:194
 generic_shutdown_super+0x159/0x3d0 fs/super.c:646
 kill_block_super+0x3b/0x90 fs/super.c:1680
 deactivate_locked_super+0xbe/0x1a0 fs/super.c:477
 deactivate_super+0xde/0x100 fs/super.c:510
 cleanup_mnt+0x222/0x450 fs/namespace.c:1267
 task_work_run+0x14f/0x250 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:108 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline]
 syscall_exit_to_user_mode+0x281/0x2b0 kernel/entry/common.c:212
 do_syscall_64+0xe5/0x270 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

The buggy address belongs to the object at ffff8880272d2800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 264 bytes inside of
 freed 1024-byte region [ffff8880272d2800, ffff8880272d2c00)

The buggy address belongs to the physical page:
page:ffffea00009cb400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x272d0
head:ffffea00009cb400 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888014c42dc0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4910, tgid 4910 (dhcpcd-run-hook), ts 31763109865, free_ts 31737584223
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1533
 prep_new_page mm/page_alloc.c:1540 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311
 __alloc_pages+0x22f/0x2440 mm/page_alloc.c:4567
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page mm/slub.c:2190 [inline]
 allocate_slab mm/slub.c:2354 [inline]
 new_slab+0xcc/0x3a0 mm/slub.c:2407
 ___slab_alloc+0x4af/0x19a0 mm/slub.c:3540
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3625
 __slab_alloc_node mm/slub.c:3678 [inline]
 slab_alloc_node mm/slub.c:3850 [inline]
 __do_kmalloc_node mm/slub.c:3980 [inline]
 __kmalloc+0x3b8/0x440 mm/slub.c:3994
 kmalloc include/linux/slab.h:594 [inline]
 load_elf_phdrs+0x103/0x210 fs/binfmt_elf.c:526
 load_elf_binary+0x14dc/0x4e40 fs/binfmt_elf.c:955
 search_binary_handler fs/exec.c:1783 [inline]
 exec_binprm fs/exec.c:1825 [inline]
 bprm_execve fs/exec.c:1877 [inline]
 bprm_execve+0x70a/0x1980 fs/exec.c:1853
 do_execveat_common.isra.0+0x5cf/0x750 fs/exec.c:1984
 do_execve fs/exec.c:2058 [inline]
 __do_sys_execve fs/exec.c:2134 [inline]
 __se_sys_execve fs/exec.c:2129 [inline]
 __x64_sys_execve+0x8c/0xb0 fs/exec.c:2129
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6f/0x77
page last free pid 4909 tgid 4909 stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1140 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2346
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2486
 qlink_free mm/kasan/quarantine.c:160 [inline]
 qlist_free_all+0x58/0x150 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:324
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3813 [inline]
 slab_alloc_node mm/slub.c:3860 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3867
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:140
 getname_flags include/linux/audit.h:322 [inline]
 getname+0x90/0xe0 fs/namei.c:219
 do_sys_openat2+0x104/0x1e0 fs/open.c:1398
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_openat fs/open.c:1435 [inline]
 __se_sys_openat fs/open.c:1430 [inline]
 __x64_sys_openat+0x175/0x210 fs/open.c:1430
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

Memory state around the buggy address:
 ffff8880272d2800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880272d2880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880272d2900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8880272d2980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880272d2a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

Re: [syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[Edward Adam Davis]

please test uaf in jfs_syncpt

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

diff --git a/fs/jfs/jfs_incore.h b/fs/jfs/jfs_incore.h
index dd4264aa9bed..15955dd86bfd 100644
--- a/fs/jfs/jfs_incore.h
+++ b/fs/jfs/jfs_incore.h
@@ -197,6 +197,7 @@ struct jfs_sb_info {
 	kgid_t		gid;		/* gid to override on-disk gid */
 	uint		umask;		/* umask to override on-disk umask */
 	uint		minblks_trim;	/* minimum blocks, for online trim */
+	struct mutex log_mutex;
 };
 
 /* jfs_sb_info commit_state */
diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
index be17e3c43582..bd30b93e435c 100644
--- a/fs/jfs/jfs_txnmgr.c
+++ b/fs/jfs/jfs_txnmgr.c
@@ -2665,6 +2665,9 @@ static void txLazyCommit(struct tblock * tblk)
 
 	log = (struct jfs_log *) JFS_SBI(tblk->sb)->log;
 
+	if (!log)
+		return;
+
 	spin_lock_irq(&log->gclock);	// LOGGC_LOCK
 
 	tblk->flag |= tblkGC_COMMITTED;
@@ -2730,7 +2733,9 @@ int jfs_lazycommit(void *arg)
 				list_del(&tblk->cqueue);
 
 				LAZY_UNLOCK(flags);
+				mutex_lock(&sbi->log_mutex);
 				txLazyCommit(tblk);
+				mutex_unlock(&sbi->log_mutex);
 				LAZY_LOCK(flags);
 
 				sbi->commit_state &= ~IN_LAZYCOMMIT;
diff --git a/fs/jfs/jfs_umount.c b/fs/jfs/jfs_umount.c
index 8ec43f53f686..04788cf3a471 100644
--- a/fs/jfs/jfs_umount.c
+++ b/fs/jfs/jfs_umount.c
@@ -51,6 +51,7 @@ int jfs_umount(struct super_block *sb)
 	 *
 	 * if mounted read-write and log based recovery was enabled
 	 */
+	mutex_lock(&sbi->log_mutex);
 	if ((log = sbi->log))
 		/*
 		 * Wait for outstanding transactions to be written to log:
@@ -113,6 +114,7 @@ int jfs_umount(struct super_block *sb)
 		 */
 		rc = lmLogClose(sb);
 	}
+	mutex_unlock(&sbi->log_mutex);
 	jfs_info("UnMount JFS Complete: rc = %d", rc);
 	return rc;
 }
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index 8d8e556bd610..cf291bdd094f 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c
@@ -504,6 +504,7 @@ static int jfs_fill_super(struct super_block *sb, void *data, int silent)
 	sbi->uid = INVALID_UID;
 	sbi->gid = INVALID_GID;
 	sbi->umask = -1;
+	mutex_init(&sbi->log_mutex);
 
 	/* initialize the mount flag and determine the default error handler */
 	flag = JFS_ERR_REMOUNT_RO;

Re: [syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in jfs_lazycommit

==================================================================
BUG: KASAN: slab-use-after-free in jfs_lazycommit+0xa54/0xb60 fs/jfs/jfs_txnmgr.c:2741
Read of size 4 at addr ffff888043198894 by task jfsCommit/132

CPU: 2 PID: 132 Comm: jfsCommit Not tainted 6.8.0-rc5-syzkaller-gb401b621758e-dirty #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc4/0x620 mm/kasan/report.c:488
 kasan_report+0xda/0x110 mm/kasan/report.c:601
 jfs_lazycommit+0xa54/0xb60 fs/jfs/jfs_txnmgr.c:2741
 kthread+0x2c6/0x3b0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242
 </TASK>

Allocated by task 5671:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:372 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:389
 kmalloc include/linux/slab.h:590 [inline]
 kzalloc include/linux/slab.h:711 [inline]
 jfs_fill_super+0xe5/0xd40 fs/jfs/super.c:495
 mount_bdev+0x1e3/0x2d0 fs/super.c:1663
 legacy_get_tree+0x109/0x220 fs/fs_context.c:662
 vfs_get_tree+0x8f/0x380 fs/super.c:1784
 do_new_mount fs/namespace.c:3352 [inline]
 path_mount+0x14ea/0x1f20 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount fs/namespace.c:3875 [inline]
 __x64_sys_mount+0x297/0x320 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

Freed by task 5422:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640
 poison_slab_object mm/kasan/common.c:241 [inline]
 __kasan_slab_free+0x121/0x1c0 mm/kasan/common.c:257
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2121 [inline]
 slab_free mm/slub.c:4299 [inline]
 kfree+0x124/0x370 mm/slub.c:4409
 generic_shutdown_super+0x159/0x3d0 fs/super.c:646
 kill_block_super+0x3b/0x90 fs/super.c:1680
 deactivate_locked_super+0xbe/0x1a0 fs/super.c:477
 deactivate_super+0xde/0x100 fs/super.c:510
 cleanup_mnt+0x222/0x450 fs/namespace.c:1267
 task_work_run+0x14f/0x250 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:108 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline]
 syscall_exit_to_user_mode+0x281/0x2b0 kernel/entry/common.c:212
 do_syscall_64+0xe5/0x270 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

The buggy address belongs to the object at ffff888043198800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 148 bytes inside of
 freed 512-byte region [ffff888043198800, ffff888043198a00)

The buggy address belongs to the physical page:
page:ffffea00010c6600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x43198
head:ffffea00010c6600 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888014c42c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5416, tgid 5416 (syz-executor.2), ts 82216613876, free_ts 60094503130
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1533
 prep_new_page mm/page_alloc.c:1540 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311
 __alloc_pages+0x22f/0x2440 mm/page_alloc.c:4567
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page mm/slub.c:2190 [inline]
 allocate_slab mm/slub.c:2354 [inline]
 new_slab+0xcc/0x3a0 mm/slub.c:2407
 ___slab_alloc+0x4af/0x19a0 mm/slub.c:3540
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3625
 __slab_alloc_node mm/slub.c:3678 [inline]
 slab_alloc_node mm/slub.c:3850 [inline]
 __do_kmalloc_node mm/slub.c:3980 [inline]
 __kmalloc+0x3b8/0x440 mm/slub.c:3994
 kmalloc include/linux/slab.h:594 [inline]
 kzalloc include/linux/slab.h:711 [inline]
 fib6_info_alloc+0x40/0x100 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x337/0x1b70 net/ipv6/route.c:3749
 ip6_route_add+0x26/0x150 net/ipv6/route.c:3843
 addrconf_add_mroute+0x1de/0x350 net/ipv6/addrconf.c:2501
 addrconf_add_dev+0x14e/0x1c0 net/ipv6/addrconf.c:2519
 inet6_addr_add+0x1a8/0xbe0 net/ipv6/addrconf.c:2965
 inet6_rtm_newaddr+0x11de/0x1ab0 net/ipv6/addrconf.c:4976
 rtnetlink_rcv_msg+0x3c7/0xe10 net/core/rtnetlink.c:6618
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2543
page last free pid 5173 tgid 5168 stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1140 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2346
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2486
 release_pages+0x51f/0x14f0 mm/swap.c:1008
 tlb_batch_pages_flush+0x9a/0x190 mm/mmu_gather.c:98
 tlb_flush_mmu_free mm/mmu_gather.c:293 [inline]
 tlb_flush_mmu mm/mmu_gather.c:300 [inline]
 tlb_finish_mmu+0x14b/0x700 mm/mmu_gather.c:392
 exit_mmap+0x3da/0xb50 mm/mmap.c:3292
 __mmput+0x12a/0x4d0 kernel/fork.c:1343
 mmput+0x62/0x70 kernel/fork.c:1365
 exit_mm kernel/exit.c:569 [inline]
 do_exit+0x9a5/0x2ad0 kernel/exit.c:858
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1020
 get_signal+0x23b9/0x2790 kernel/signal.c:2893
 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline]
 syscall_exit_to_user_mode+0x156/0x2b0 kernel/entry/common.c:212
 do_syscall_64+0xe5/0x270 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

Memory state around the buggy address:
 ffff888043198780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888043198800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888043198880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff888043198900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888043198980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


Tested on:

commit:         b401b621 Linux 6.8-rc5
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=16850158180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c6a2287897dfeb9a
dashboard link: https://syzkaller.appspot.com/bug?extid=c244f4a09ca85dd2ebc1
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1699e1d0180000

Re: [syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[Edward Adam Davis]

please test uaf in jfs_syncpt

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

diff --git a/fs/jfs/jfs_incore.h b/fs/jfs/jfs_incore.h
index dd4264aa9bed..15955dd86bfd 100644
--- a/fs/jfs/jfs_incore.h
+++ b/fs/jfs/jfs_incore.h
@@ -197,6 +197,7 @@ struct jfs_sb_info {
 	kgid_t		gid;		/* gid to override on-disk gid */
 	uint		umask;		/* umask to override on-disk umask */
 	uint		minblks_trim;	/* minimum blocks, for online trim */
+	struct mutex log_mutex;
 };
 
 /* jfs_sb_info commit_state */
diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
index be17e3c43582..eb60862dc61b 100644
--- a/fs/jfs/jfs_txnmgr.c
+++ b/fs/jfs/jfs_txnmgr.c
@@ -2665,6 +2665,9 @@ static void txLazyCommit(struct tblock * tblk)
 
 	log = (struct jfs_log *) JFS_SBI(tblk->sb)->log;
 
+	if (!log)
+		return;
+
 	spin_lock_irq(&log->gclock);	// LOGGC_LOCK
 
 	tblk->flag |= tblkGC_COMMITTED;
@@ -2730,10 +2733,12 @@ int jfs_lazycommit(void *arg)
 				list_del(&tblk->cqueue);
 
 				LAZY_UNLOCK(flags);
+				mutex_lock(&sbi->log_mutex);
 				txLazyCommit(tblk);
+				sbi->commit_state &= ~IN_LAZYCOMMIT;
+				mutex_unlock(&sbi->log_mutex);
 				LAZY_LOCK(flags);
 
-				sbi->commit_state &= ~IN_LAZYCOMMIT;
 				/*
 				 * Don't continue in the for loop.  (We can't
 				 * anyway, it's unsafe!)  We want to go back to
diff --git a/fs/jfs/jfs_umount.c b/fs/jfs/jfs_umount.c
index 8ec43f53f686..04788cf3a471 100644
--- a/fs/jfs/jfs_umount.c
+++ b/fs/jfs/jfs_umount.c
@@ -51,6 +51,7 @@ int jfs_umount(struct super_block *sb)
 	 *
 	 * if mounted read-write and log based recovery was enabled
 	 */
+	mutex_lock(&sbi->log_mutex);
 	if ((log = sbi->log))
 		/*
 		 * Wait for outstanding transactions to be written to log:
@@ -113,6 +114,7 @@ int jfs_umount(struct super_block *sb)
 		 */
 		rc = lmLogClose(sb);
 	}
+	mutex_unlock(&sbi->log_mutex);
 	jfs_info("UnMount JFS Complete: rc = %d", rc);
 	return rc;
 }
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index 8d8e556bd610..cf291bdd094f 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c
@@ -504,6 +504,7 @@ static int jfs_fill_super(struct super_block *sb, void *data, int silent)
 	sbi->uid = INVALID_UID;
 	sbi->gid = INVALID_GID;
 	sbi->umask = -1;
+	mutex_init(&sbi->log_mutex);
 
 	/* initialize the mount flag and determine the default error handler */
 	flag = JFS_ERR_REMOUNT_RO;

Re: [syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+c244f4a09ca85dd2ebc1@syzkaller.appspotmail.com

Tested on:

commit:         b401b621 Linux 6.8-rc5
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=10b4278a180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c6a2287897dfeb9a
dashboard link: https://syzkaller.appspot.com/bug?extid=c244f4a09ca85dd2ebc1
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=16796c64180000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+c244f4a09ca85dd2ebc1@syzkaller.appspotmail.com
Tested-by: syzbot+c244f4a09ca85dd2ebc1@syzkaller.appspotmail.com

Tested on:

commit:         08d0d346 Merge tag 'net-7.1-rc2' of git://git.kernel.o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13663a96580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=30d0399c96ae114e
dashboard link: https://syzkaller.appspot.com/bug?extid=c244f4a09ca85dd2ebc1
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
patch:          https://syzkaller.appspot.com/x/patch.diff?x=14ca8a73980000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [jfs?] KASAN: slab-use-after-free Read in jfs_syncpt

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+c244f4a09ca85dd2ebc1@syzkaller.appspotmail.com
Tested-by: syzbot+c244f4a09ca85dd2ebc1@syzkaller.appspotmail.com

Tested on:

commit:         a293ec25 Merge tag 'linux_kselftest-fixes-7.1-rc3' of ..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17f57b48580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=30d0399c96ae114e
dashboard link: https://syzkaller.appspot.com/bug?extid=c244f4a09ca85dd2ebc1
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
patch:          https://syzkaller.appspot.com/x/patch.diff?x=14c101ce580000

Note: testing is done by a robot and is best-effort only.