[syzbot] KASAN: use-after-free Read in ring_buffer_peek
1 view
Skip to first unread message
syzbot
6:10 PM (4 hours ago) 6:10 PM
to linux-...@vger.kernel.org, syzkall...@googlegroups.com
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+685955...@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:
<TASK>
__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 <c3> 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
</TASK>
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:
<TASK>
__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 <c3> 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
</TASK>
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:
<TASK>
__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 <c3> 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
</TASK>
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:
<TASK>
__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 <c3> 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
</TASK>
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. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
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.
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
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+685955...@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:
<TASK>
__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 <c3> 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
</TASK>
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:
<TASK>
__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 <c3> 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
</TASK>
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:
<TASK>
__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 <c3> 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
</TASK>
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:
<TASK>
__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 <c3> 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
</TASK>
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. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
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.
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
Reply all
Reply to author
Forward
0 new messages