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15:10:21 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a82354d.10853dc7.22f513.0014.GAE@google.com> Subject: [syzbot] KASAN: use-after-free Read in ring_buffer_peek From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 3d6d817622b0 Merge tag 'scsi-fixes' of git://git.kernel.or.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10d17479580000 kernel config: https://syzkaller.appspot.com/x/.config?x=dd70c0851d340092 dashboard link: https://syzkaller.appspot.com/bug?extid=685955db58555575fdd2 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12910ac6580000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+685955db58555575fdd2@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in ring_buffer_peek+0x3e0/0x430 kernel/trace/ring_buffer.c:6274 Read of size 1 at addr ffff88802a4cf010 by task syz-executor989/6002 CPU: 1 UID: 0 PID: 6002 Comm: syz-executor989 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 ring_buffer_peek+0x3e0/0x430 kernel/trace/ring_buffer.c:6274 peek_next_entry+0x17a/0x250 kernel/trace/trace.c:2354 __find_next_entry+0x1ed/0x4e0 kernel/trace/trace.c:2398 trace_find_next_entry_inc+0x3d/0x1c0 kernel/trace/trace.c:2672 tracing_read_pipe+0x557/0xd60 kernel/trace/trace.c:5440 vfs_read+0x1e4/0xb40 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f588d3b7d9e Code: 08 0f 85 f5 e2 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 90 41 57 41 56 4d 89 c6 41 55 4d 89 cd 41 54 55 53 48 83 ec 08 RSP: 002b:00007f588d361198 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f588d3626c0 RCX: 00007f588d3b7d9e RDX: 0000000000001000 RSI: 00007f588d361200 RDI: 0000000000000003 RBP: 00007f588d361200 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffd0 R13: 0000000000000000 R14: 00007ffe1b5bf5a0 R15: 00007ffe1b5bf688 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a4cf flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001ddbd08 ffffea00006f0fc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x44dc0(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL|__GFP_COMP), pid 5981, tgid 5981 (syz-executor989), ts 130836230668, free_ts 170720200085 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 __alloc_pages_noprof+0xb/0x110 mm/page_alloc.c:5338 __alloc_pages_node_noprof include/linux/gfp.h:291 [inline] alloc_pages_node_noprof include/linux/gfp.h:318 [inline] alloc_cpu_data+0x60/0x160 kernel/trace/ring_buffer.c:427 __rb_allocate_pages+0xbd5/0x10a0 kernel/trace/ring_buffer.c:2436 ring_buffer_resize+0x6df/0x1e80 kernel/trace/ring_buffer.c:3274 __tracing_resize_ring_buffer.part.0+0x52/0x1f0 kernel/trace/trace.c:4738 __tracing_resize_ring_buffer kernel/trace/trace.c:4732 [inline] tracing_update_buffers+0xd4/0xf0 kernel/trace/trace.c:4977 system_enable_write+0x151/0x300 kernel/trace/trace_events.c:2020 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 6003 tgid 5981 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 free_buffer_page kernel/trace/ring_buffer.c:398 [inline] ring_buffer_subbuf_order_set+0x1325/0x18e0 kernel/trace/ring_buffer.c:7444 buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802a4cef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802a4cef80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff88802a4cf000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88802a4cf080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88802a4cf100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== ================================================================== BUG: KASAN: use-after-free in ring_buffer_event_length+0x218/0x260 kernel/trace/ring_buffer.c:266 Read of size 4 at addr ffff88802a4cf010 by task syz-executor989/6002 CPU: 0 UID: 0 PID: 6002 Comm: syz-executor989 Tainted: G B syzkaller #0 PREEMPT(full) Tainted: [B]=BAD_PAGE Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 ring_buffer_event_length+0x218/0x260 kernel/trace/ring_buffer.c:266 peek_next_entry+0x198/0x250 kernel/trace/trace.c:2359 __find_next_entry+0x1ed/0x4e0 kernel/trace/trace.c:2398 trace_find_next_entry_inc+0x3d/0x1c0 kernel/trace/trace.c:2672 tracing_read_pipe+0x557/0xd60 kernel/trace/trace.c:5440 vfs_read+0x1e4/0xb40 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f588d3b7d9e Code: 08 0f 85 f5 e2 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 90 41 57 41 56 4d 89 c6 41 55 4d 89 cd 41 54 55 53 48 83 ec 08 RSP: 002b:00007f588d361198 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f588d3626c0 RCX: 00007f588d3b7d9e RDX: 0000000000001000 RSI: 00007f588d361200 RDI: 0000000000000003 RBP: 00007f588d361200 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffd0 R13: 0000000000000000 R14: 00007ffe1b5bf5a0 R15: 00007ffe1b5bf688 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a4cf flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001ddbd08 ffffea00006f0fc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x44dc0(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL|__GFP_COMP), pid 5981, tgid 5981 (syz-executor989), ts 130836230668, free_ts 170720200085 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 __alloc_pages_noprof+0xb/0x110 mm/page_alloc.c:5338 __alloc_pages_node_noprof include/linux/gfp.h:291 [inline] alloc_pages_node_noprof include/linux/gfp.h:318 [inline] alloc_cpu_data+0x60/0x160 kernel/trace/ring_buffer.c:427 __rb_allocate_pages+0xbd5/0x10a0 kernel/trace/ring_buffer.c:2436 ring_buffer_resize+0x6df/0x1e80 kernel/trace/ring_buffer.c:3274 __tracing_resize_ring_buffer.part.0+0x52/0x1f0 kernel/trace/trace.c:4738 __tracing_resize_ring_buffer kernel/trace/trace.c:4732 [inline] tracing_update_buffers+0xd4/0xf0 kernel/trace/trace.c:4977 system_enable_write+0x151/0x300 kernel/trace/trace_events.c:2020 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 6003 tgid 5981 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 free_buffer_page kernel/trace/ring_buffer.c:398 [inline] ring_buffer_subbuf_order_set+0x1325/0x18e0 kernel/trace/ring_buffer.c:7444 buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802a4cef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802a4cef80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff88802a4cf000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88802a4cf080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88802a4cf100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== ================================================================== BUG: KASAN: use-after-free in rb_event_data_length kernel/trace/ring_buffer.c:198 [inline] BUG: KASAN: use-after-free in rb_event_length kernel/trace/ring_buffer.c:227 [inline] BUG: KASAN: use-after-free in ring_buffer_event_length+0x243/0x260 kernel/trace/ring_buffer.c:269 Read of size 1 at addr ffff88802a4cf010 by task syz-executor989/6002 CPU: 0 UID: 0 PID: 6002 Comm: syz-executor989 Tainted: G B syzkaller #0 PREEMPT(full) Tainted: [B]=BAD_PAGE Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 rb_event_data_length kernel/trace/ring_buffer.c:198 [inline] rb_event_length kernel/trace/ring_buffer.c:227 [inline] ring_buffer_event_length+0x243/0x260 kernel/trace/ring_buffer.c:269 peek_next_entry+0x198/0x250 kernel/trace/trace.c:2359 __find_next_entry+0x1ed/0x4e0 kernel/trace/trace.c:2398 trace_find_next_entry_inc+0x3d/0x1c0 kernel/trace/trace.c:2672 tracing_read_pipe+0x557/0xd60 kernel/trace/trace.c:5440 vfs_read+0x1e4/0xb40 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f588d3b7d9e Code: 08 0f 85 f5 e2 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 90 41 57 41 56 4d 89 c6 41 55 4d 89 cd 41 54 55 53 48 83 ec 08 RSP: 002b:00007f588d361198 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f588d3626c0 RCX: 00007f588d3b7d9e RDX: 0000000000001000 RSI: 00007f588d361200 RDI: 0000000000000003 RBP: 00007f588d361200 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffd0 R13: 0000000000000000 R14: 00007ffe1b5bf5a0 R15: 00007ffe1b5bf688 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a4cf flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001ddbd08 ffffea00006f0fc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x44dc0(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL|__GFP_COMP), pid 5981, tgid 5981 (syz-executor989), ts 130836230668, free_ts 170720200085 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 __alloc_pages_noprof+0xb/0x110 mm/page_alloc.c:5338 __alloc_pages_node_noprof include/linux/gfp.h:291 [inline] alloc_pages_node_noprof include/linux/gfp.h:318 [inline] alloc_cpu_data+0x60/0x160 kernel/trace/ring_buffer.c:427 __rb_allocate_pages+0xbd5/0x10a0 kernel/trace/ring_buffer.c:2436 ring_buffer_resize+0x6df/0x1e80 kernel/trace/ring_buffer.c:3274 __tracing_resize_ring_buffer.part.0+0x52/0x1f0 kernel/trace/trace.c:4738 __tracing_resize_ring_buffer kernel/trace/trace.c:4732 [inline] tracing_update_buffers+0xd4/0xf0 kernel/trace/trace.c:4977 system_enable_write+0x151/0x300 kernel/trace/trace_events.c:2020 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 6003 tgid 5981 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 free_buffer_page kernel/trace/ring_buffer.c:398 [inline] ring_buffer_subbuf_order_set+0x1325/0x18e0 kernel/trace/ring_buffer.c:7444 buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802a4cef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802a4cef80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff88802a4cf000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88802a4cf080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88802a4cf100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== ================================================================== BUG: KASAN: use-after-free in rb_event_data kernel/trace/ring_buffer.c:284 [inline] BUG: KASAN: use-after-free in ring_buffer_event_data+0x129/0x150 kernel/trace/ring_buffer.c:300 Read of size 4 at addr ffff88802a4cf010 by task syz-executor989/6002 CPU: 1 UID: 0 PID: 6002 Comm: syz-executor989 Tainted: G B syzkaller #0 PREEMPT(full) Tainted: [B]=BAD_PAGE Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 rb_event_data kernel/trace/ring_buffer.c:284 [inline] ring_buffer_event_data+0x129/0x150 kernel/trace/ring_buffer.c:300 peek_next_entry+0x1d3/0x250 kernel/trace/trace.c:2360 __find_next_entry+0x1ed/0x4e0 kernel/trace/trace.c:2398 trace_find_next_entry_inc+0x3d/0x1c0 kernel/trace/trace.c:2672 tracing_read_pipe+0x557/0xd60 kernel/trace/trace.c:5440 vfs_read+0x1e4/0xb40 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f588d3b7d9e Code: 08 0f 85 f5 e2 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 90 41 57 41 56 4d 89 c6 41 55 4d 89 cd 41 54 55 53 48 83 ec 08 RSP: 002b:00007f588d361198 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f588d3626c0 RCX: 00007f588d3b7d9e RDX: 0000000000001000 RSI: 00007f588d361200 RDI: 0000000000000003 RBP: 00007f588d361200 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffd0 R13: 0000000000000000 R14: 00007ffe1b5bf5a0 R15: 00007ffe1b5bf688 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a4cf flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001ddbd08 ffffea00006f0fc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x44dc0(GFP_KERNEL|__GFP_ZERO|__GFP_RETRY_MAYFAIL|__GFP_COMP), pid 5981, tgid 5981 (syz-executor989), ts 130836230668, free_ts 170720200085 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 __alloc_pages_noprof+0xb/0x110 mm/page_alloc.c:5338 __alloc_pages_node_noprof include/linux/gfp.h:291 [inline] alloc_pages_node_noprof include/linux/gfp.h:318 [inline] alloc_cpu_data+0x60/0x160 kernel/trace/ring_buffer.c:427 __rb_allocate_pages+0xbd5/0x10a0 kernel/trace/ring_buffer.c:2436 ring_buffer_resize+0x6df/0x1e80 kernel/trace/ring_buffer.c:3274 __tracing_resize_ring_buffer.part.0+0x52/0x1f0 kernel/trace/trace.c:4738 __tracing_resize_ring_buffer kernel/trace/trace.c:4732 [inline] tracing_update_buffers+0xd4/0xf0 kernel/trace/trace.c:4977 system_enable_write+0x151/0x300 kernel/trace/trace_events.c:2020 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 6003 tgid 5981 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 free_buffer_page kernel/trace/ring_buffer.c:398 [inline] ring_buffer_subbuf_order_set+0x1325/0x18e0 kernel/trace/ring_buffer.c:7444 buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802a4cef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802a4cef80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff88802a4cf000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88802a4cf080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88802a4cf100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== --- This report is generated by a bot. 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