ci starts bisection 2023-03-04 05:42:52.850411822 +0000 UTC m=+242899.221664674 bisecting fixing commit since 1b929c02afd37871d5afb9d498426f83432e71c2 building syzkaller on 44712fbc6b687170984c3562336a415b56d82607 ensuring issue is reproducible on original commit 1b929c02afd37871d5afb9d498426f83432e71c2 testing commit 1b929c02afd37871d5afb9d498426f83432e71c2 gcc compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: b5b3c4a0cbe55236c101d62b35c8d1574692be1deb251081a0bd94764f865b9a all runs: crashed: KASAN: use-after-free Read in gsm_cleanup_mux testing current HEAD 0988a0ea791999ebbf95693f2676381825b05033 testing commit 0988a0ea791999ebbf95693f2676381825b05033 gcc compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: c1e7c6d379cba636b30cf331aeaf85220d514e4ad43c61e2e0f275730e438092 all runs: crashed: KASAN: slab-use-after-free Read in gsm_cleanup_mux revisions tested: 2, total time: 24m58.227802485s (build: 18m2.554400454s, test: 6m11.328134859s) the crash still happens on HEAD commit msg: Merge tag 'for-v6.3-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply crash: KASAN: slab-use-after-free Read in gsm_cleanup_mux ================================================================== BUG: KASAN: slab-use-after-free in gsm_cleanup_mux+0x6b1/0x730 drivers/tty/n_gsm.c:2906 Read of size 4 at addr ffff88801d69800c by task syz-executor.0/5859 CPU: 0 PID: 5859 Comm: syz-executor.0 Not tainted 6.2.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x64/0xb0 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:319 print_report mm/kasan/report.c:430 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:536 gsm_cleanup_mux+0x6b1/0x730 drivers/tty/n_gsm.c:2906 gsm_config drivers/tty/n_gsm.c:3180 [inline] gsmld_ioctl+0x6ac/0x1240 drivers/tty/n_gsm.c:3571 tty_ioctl+0x6fb/0x12e0 drivers/tty/tty_io.c:2786 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x123/0x190 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fab6508c0a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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:00007fab65d1d168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fab651ac050 RCX: 00007fab6508c0a9 RDX: 0000000020000040 RSI: 00000000404c4701 RDI: 0000000000000005 RBP: 00007fab650e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdfc0e298f R14: 00007fab65d1d300 R15: 0000000000022000 Allocated by task 5855: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] ____kasan_kmalloc mm/kasan/common.c:333 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] gsm_dlci_alloc+0x41/0x790 drivers/tty/n_gsm.c:2472 gsm_activate_mux drivers/tty/n_gsm.c:2954 [inline] gsm_config drivers/tty/n_gsm.c:3208 [inline] gsmld_ioctl+0x998/0x1240 drivers/tty/n_gsm.c:3571 tty_ioctl+0x6fb/0x12e0 drivers/tty/tty_io.c:2786 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x123/0x190 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5855: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0xaf/0x2d0 mm/slub.c:3800 dlci_put drivers/tty/n_gsm.c:2535 [inline] gsm_dlci_release drivers/tty/n_gsm.c:2568 [inline] gsm_cleanup_mux+0x2c3/0x730 drivers/tty/n_gsm.c:2928 gsm_config drivers/tty/n_gsm.c:3180 [inline] gsmld_ioctl+0x6ac/0x1240 drivers/tty/n_gsm.c:3571 tty_ioctl+0x6fb/0x12e0 drivers/tty/tty_io.c:2786 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x123/0x190 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88801d698000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 12 bytes inside of freed 2048-byte region [ffff88801d698000, ffff88801d698800) The buggy address belongs to the physical page: page:ffffea000075a600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d698 head:ffffea000075a600 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888011442000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 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 5080, tgid 5080 (syz-executor.0), ts 31539736650, free_ts 26417858904 prep_new_page mm/page_alloc.c:2552 [inline] get_page_from_freelist+0x1190/0x2f80 mm/page_alloc.c:4325 __alloc_pages+0x1cb/0x5c0 mm/page_alloc.c:5591 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x390 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292 __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x136/0x330 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:966 [inline] __kmalloc_node_track_caller+0x4b/0xc0 mm/slab_common.c:987 kmalloc_reserve+0xbf/0x1d0 net/core/skbuff.c:539 pskb_expand_head+0x1d9/0xfe0 net/core/skbuff.c:1995 netlink_trim+0x18f/0x1f0 net/netlink/af_netlink.c:1321 netlink_broadcast+0x57/0xa80 net/netlink/af_netlink.c:1517 nlmsg_multicast include/net/netlink.h:1083 [inline] nlmsg_notify+0x69/0x1c0 net/netlink/af_netlink.c:2617 __dev_notify_flags+0x1a0/0x240 net/core/dev.c:8562 rtnl_configure_link+0x134/0x220 net/core/rtnetlink.c:3270 rtnl_newlink_create net/core/rtnetlink.c:3448 [inline] __rtnl_newlink+0xddc/0x1520 net/core/rtnetlink.c:3657 rtnl_newlink+0x5e/0x90 net/core/rtnetlink.c:3670 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1453 [inline] free_pcp_prepare+0x65a/0xb40 mm/page_alloc.c:1503 free_unref_page_prepare mm/page_alloc.c:3387 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3482 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2637 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x192/0x220 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x63/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:769 [inline] slab_alloc_node mm/slub.c:3452 [inline] slab_alloc mm/slub.c:3460 [inline] __kmem_cache_alloc_lru mm/slub.c:3467 [inline] kmem_cache_alloc+0x175/0x320 mm/slub.c:3476 getname_flags.part.0+0x4a/0x440 fs/namei.c:140 vfs_fstatat+0x39/0x70 fs/stat.c:275 __do_sys_newfstatat+0x6b/0xc0 fs/stat.c:446 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88801d697f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801d697f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801d698000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801d698080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801d698100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================