================================================================== BUG: KASAN: slab-use-after-free in smk_access+0x54/0x148 security/smack/smack_access.c:147 Read at addr f9f000001818a890 by task syz.0.3697/15723 Pointer tag: [f9], memory tag: [fe] CPU: 1 UID: 0 PID: 15723 Comm: syz.0.3697 Not tainted 6.11.0-syzkaller-02574-ga430d95c5efa #0 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x94/0xec arch/arm64/kernel/stacktrace.c:319 show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:326 __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x78/0x90 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x108/0x618 mm/kasan/report.c:488 kasan_report+0x88/0xac mm/kasan/report.c:601 report_tag_fault arch/arm64/mm/fault.c:332 [inline] do_tag_recovery arch/arm64/mm/fault.c:344 [inline] __do_kernel_fault+0x170/0x1c8 arch/arm64/mm/fault.c:386 do_bad_area arch/arm64/mm/fault.c:486 [inline] do_tag_check_fault+0x78/0x8c arch/arm64/mm/fault.c:803 do_mem_abort+0x44/0x94 arch/arm64/mm/fault.c:879 el1_abort+0x40/0x60 arch/arm64/kernel/entry-common.c:432 el1h_64_sync_handler+0xd8/0xe4 arch/arm64/kernel/entry-common.c:492 el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:593 smk_access+0x54/0x148 security/smack/smack_access.c:147 smack_watch_key+0xe0/0xf8 security/smack/smack_lsm.c:4656 security_watch_key+0x58/0x148 security/security.c:4448 keyctl_watch_key+0xb0/0x1cc security/keys/keyctl.c:1813 __do_sys_keyctl security/keys/keyctl.c:2021 [inline] __se_sys_keyctl security/keys/keyctl.c:1874 [inline] __arm64_sys_keyctl+0x50/0x290 security/keys/keyctl.c:1874 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x48/0x110 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151 el0_svc+0x34/0xec arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598 Allocated by task 8093: kasan_save_stack+0x3c/0x64 mm/kasan/common.c:47 save_stack_info+0x40/0x158 mm/kasan/tags.c:106 kasan_save_alloc_info+0x14/0x20 mm/kasan/tags.c:142 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] poison_kmalloc_redzone mm/kasan/common.c:343 [inline] __kasan_kmalloc+0xb4/0xb8 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:4159 [inline] __kmalloc_node_noprof+0x1c8/0x37c mm/slub.c:4165 kmalloc_node_noprof include/linux/slab.h:717 [inline] __vmalloc_area_node mm/vmalloc.c:3642 [inline] __vmalloc_node_range_noprof+0x1a8/0x858 mm/vmalloc.c:3837 __vmalloc_node_noprof mm/vmalloc.c:3902 [inline] vzalloc_noprof+0x94/0xa4 mm/vmalloc.c:3975 alloc_counters.isra.0+0x20/0x140 net/ipv4/netfilter/ip_tables.c:799 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:821 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1022 [inline] do_ipt_get_ctl+0x27c/0x49c net/ipv4/netfilter/ip_tables.c:1668 nf_getsockopt+0x60/0x8c net/netfilter/nf_sockopt.c:116 ip_getsockopt+0xe8/0x16c net/ipv4/ip_sockglue.c:1777 tcp_getsockopt+0x20/0x48 net/ipv4/tcp.c:4670 sock_common_getsockopt+0x1c/0x28 net/core/sock.c:3776 do_sock_getsockopt+0x148/0x288 net/socket.c:2392 __sys_getsockopt+0x78/0xd0 net/socket.c:2421 __do_sys_getsockopt net/socket.c:2431 [inline] __se_sys_getsockopt net/socket.c:2428 [inline] __arm64_sys_getsockopt+0x24/0x34 net/socket.c:2428 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x48/0x110 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151 el0_svc+0x34/0xec arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598 Freed by task 8093: kasan_save_stack+0x3c/0x64 mm/kasan/common.c:47 save_stack_info+0x40/0x158 mm/kasan/tags.c:106 kasan_save_free_info+0x18/0x24 mm/kasan/tags.c:147 poison_slab_object+0x178/0x1c0 mm/kasan/common.c:240 __kasan_slab_free+0x30/0x48 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2250 [inline] slab_free mm/slub.c:4474 [inline] kfree+0xd8/0x28c mm/slub.c:4595 kvfree+0x3c/0x4c mm/util.c:696 vfree+0xf0/0x34c mm/vmalloc.c:3371 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:866 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1022 [inline] do_ipt_get_ctl+0x3c0/0x49c net/ipv4/netfilter/ip_tables.c:1668 nf_getsockopt+0x60/0x8c net/netfilter/nf_sockopt.c:116 ip_getsockopt+0xe8/0x16c net/ipv4/ip_sockglue.c:1777 tcp_getsockopt+0x20/0x48 net/ipv4/tcp.c:4670 sock_common_getsockopt+0x1c/0x28 net/core/sock.c:3776 do_sock_getsockopt+0x148/0x288 net/socket.c:2392 __sys_getsockopt+0x78/0xd0 net/socket.c:2421 __do_sys_getsockopt net/socket.c:2431 [inline] __se_sys_getsockopt net/socket.c:2428 [inline] __arm64_sys_getsockopt+0x24/0x34 net/socket.c:2428 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x48/0x110 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151 el0_svc+0x34/0xec arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598 The buggy address belongs to the object at fff000001818a890 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 0 bytes inside of 16-byte region [fff000001818a890, fff000001818a8a0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xf5f000001818a020 pfn:0x5818a flags: 0x1ffc00000000000(node=0|zone=0|lastcpupid=0x7ff|kasantag=0x0) page_type: 0xfdffffff(slab) raw: 01ffc00000000000 faf0000003001400 dead000000000122 0000000000000000 raw: f5f000001818a020 000000008100005e 00000001fdffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: fff000001818a600: fe f6 fa fe f5 f4 fe fe fe fe fe fc fe fe f6 f6 fff000001818a700: fe f7 fe fe f7 fe fe fe fe fe fe fe fe fe fe fe >fff000001818a800: fe f5 fe fe fb fe fe f9 fe fe fe fc fd fe fc fe ^ fff000001818a900: fe fe f7 f1 fe fe fe f0 f8 fe fe fe fe fe fe fd fff000001818aa00: fe fe fe fe fc fe fe fe fe f8 fe fe fe fe fb f9 ================================================================== Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x0000000096000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 52-bit VAs, pgdp=000000004626d200 [0000000000000000] pgd=0800000048e9c003, p4d=0800000072cae003, pud=080000004a260003, pmd=0000000000000000 Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: CPU: 1 UID: 0 PID: 15723 Comm: syz.0.3697 Tainted: G B 6.11.0-syzkaller-02574-ga430d95c5efa #0 Tainted: [B]=BAD_PAGE Hardware name: linux,dummy-virt (DT) pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : __pi_strlen+0x14/0x150 arch/arm64/lib/strlen.S:87 lr : audit_log_untrustedstring+0x20/0x40 kernel/audit.c:2135 sp : ffff8000880d3c00 x29: ffff8000880d3c00 x28: f5f00000265d8000 x27: 0000000000000000 x26: 0000000000000000 x25: 0000000000000000 x24: f8f0000028a4d6c0 x23: 00000000fffffff3 x22: 0000000000000000 x21: ffff800080511918 x20: fdf00000030423c0 x19: 0000000000000000 x18: ffffffffffffffff x17: ffff800080027db0 x16: ffff8000804e91f0 x15: ffff8000880d39e0 x14: 0000000000000000 x13: fdf00000185b381f x12: ffff800080027eb8 x11: ffff800080011558 x10: 000000000000005f x9 : 0000000000000370 x8 : 0101010101010101 x7 : 00000000000006c0 x6 : 0000000000000059 x5 : fdf00000185b3859 x4 : 0000000000000000 x3 : 0000000000000061 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: __pi_strlen+0x14/0x150 arch/arm64/lib/strlen.S:86 smack_log_callback+0x7c/0xc8 security/smack/smack_access.c:321 common_lsm_audit+0x5c/0x85c security/lsm_audit.c:456 smack_log+0xec/0x140 security/smack/smack_access.c:383 smk_access+0x104/0x148 security/smack/smack_access.c:199 smack_watch_key+0xe0/0xf8 security/smack/smack_lsm.c:4656 security_watch_key+0x58/0x148 security/security.c:4448 keyctl_watch_key+0xb0/0x1cc security/keys/keyctl.c:1813 __do_sys_keyctl security/keys/keyctl.c:2021 [inline] __se_sys_keyctl security/keys/keyctl.c:1874 [inline] __arm64_sys_keyctl+0x50/0x290 security/keys/keyctl.c:1874 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x48/0x110 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151 el0_svc+0x34/0xec arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598 Code: 92400c04 b200c3e8 f100009f 5400088c (a9400c02) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 92400c04 and x4, x0, #0xf 4: b200c3e8 mov x8, #0x101010101010101 // #72340172838076673 8: f100009f cmp x4, #0x0 c: 5400088c b.gt 0x11c * 10: a9400c02 ldp x2, x3, [x0] <-- trapping instruction