From: syzbot <syzbot+321914d39d7553cca1e7@syzkaller.appspotmail.com>
To: axboe@kernel.dk, io-uring@vger.kernel.org,
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: [syzbot] [io-uring?] memory leak in iovec_from_user (5)
Date: Sun, 18 Jan 2026 10:41:22 -0800 [thread overview]
Message-ID: <696d2952.050a0220.3390f1.0022.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: c537e12daeec Merge tag 'bpf-fixes' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17c91d9a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=87bc41cae23d2144
dashboard link: https://syzkaller.appspot.com/bug?extid=321914d39d7553cca1e7
compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16a8d5fa580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b4f60c3c9800/disk-c537e12d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5f2c0a541579/vmlinux-c537e12d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/32dcd74ba443/bzImage-c537e12d.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+321914d39d7553cca1e7@syzkaller.appspotmail.com
BUG: memory leak
unreferenced object 0xffff8881228893e0 (size 32):
comm "syz.6.23", pid 6169, jiffies 4294942659
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................
backtrace (crc ccaa009e):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kmalloc_array_noprof include/linux/slab.h:1003 [inline]
iovec_from_user lib/iov_iter.c:1321 [inline]
iovec_from_user+0x108/0x140 lib/iov_iter.c:1304
__import_iovec+0x71/0x350 lib/iov_iter.c:1375
io_import_vec io_uring/rw.c:99 [inline]
__io_import_rw_buffer+0x1e2/0x260 io_uring/rw.c:120
io_import_rw_buffer io_uring/rw.c:139 [inline]
io_rw_do_import io_uring/rw.c:313 [inline]
io_prep_rw+0xb5/0x120 io_uring/rw.c:325
io_prep_rwv io_uring/rw.c:343 [inline]
io_prep_writev+0x23/0x80 io_uring/rw.c:363
io_init_req io_uring/io_uring.c:2235 [inline]
io_submit_sqe io_uring/io_uring.c:2282 [inline]
io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2435
__do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3285
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff888122889400 (size 32):
comm "syz.6.23", pid 6169, jiffies 4294942659
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................
backtrace (crc ccaa009e):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kmalloc_array_noprof include/linux/slab.h:1003 [inline]
iovec_from_user lib/iov_iter.c:1321 [inline]
iovec_from_user+0x108/0x140 lib/iov_iter.c:1304
__import_iovec+0x71/0x350 lib/iov_iter.c:1375
io_import_vec io_uring/rw.c:99 [inline]
__io_import_rw_buffer+0x1e2/0x260 io_uring/rw.c:120
io_import_rw_buffer io_uring/rw.c:139 [inline]
io_rw_do_import io_uring/rw.c:313 [inline]
io_prep_rw+0xb5/0x120 io_uring/rw.c:325
io_prep_rwv io_uring/rw.c:343 [inline]
io_prep_writev+0x23/0x80 io_uring/rw.c:363
io_init_req io_uring/io_uring.c:2235 [inline]
io_submit_sqe io_uring/io_uring.c:2282 [inline]
io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2435
__do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3285
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff888122889420 (size 32):
comm "syz.6.23", pid 6169, jiffies 4294942659
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................
backtrace (crc ccaa009e):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kmalloc_array_noprof include/linux/slab.h:1003 [inline]
iovec_from_user lib/iov_iter.c:1321 [inline]
iovec_from_user+0x108/0x140 lib/iov_iter.c:1304
__import_iovec+0x71/0x350 lib/iov_iter.c:1375
io_import_vec io_uring/rw.c:99 [inline]
__io_import_rw_buffer+0x1e2/0x260 io_uring/rw.c:120
io_import_rw_buffer io_uring/rw.c:139 [inline]
io_rw_do_import io_uring/rw.c:313 [inline]
io_prep_rw+0xb5/0x120 io_uring/rw.c:325
io_prep_rwv io_uring/rw.c:343 [inline]
io_prep_writev+0x23/0x80 io_uring/rw.c:363
io_init_req io_uring/io_uring.c:2235 [inline]
io_submit_sqe io_uring/io_uring.c:2282 [inline]
io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2435
__do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3285
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff888122889440 (size 32):
comm "syz.6.23", pid 6169, jiffies 4294942659
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................
backtrace (crc ccaa009e):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kmalloc_array_noprof include/linux/slab.h:1003 [inline]
iovec_from_user lib/iov_iter.c:1321 [inline]
iovec_from_user+0x108/0x140 lib/iov_iter.c:1304
__import_iovec+0x71/0x350 lib/iov_iter.c:1375
io_import_vec io_uring/rw.c:99 [inline]
__io_import_rw_buffer+0x1e2/0x260 io_uring/rw.c:120
io_import_rw_buffer io_uring/rw.c:139 [inline]
io_rw_do_import io_uring/rw.c:313 [inline]
io_prep_rw+0xb5/0x120 io_uring/rw.c:325
io_prep_rwv io_uring/rw.c:343 [inline]
io_prep_writev+0x23/0x80 io_uring/rw.c:363
io_init_req io_uring/io_uring.c:2235 [inline]
io_submit_sqe io_uring/io_uring.c:2282 [inline]
io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2435
__do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3285
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff888122889460 (size 32):
comm "syz.6.23", pid 6169, jiffies 4294942659
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................
backtrace (crc ccaa009e):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kmalloc_array_noprof include/linux/slab.h:1003 [inline]
iovec_from_user lib/iov_iter.c:1321 [inline]
iovec_from_user+0x108/0x140 lib/iov_iter.c:1304
__import_iovec+0x71/0x350 lib/iov_iter.c:1375
io_import_vec io_uring/rw.c:99 [inline]
__io_import_rw_buffer+0x1e2/0x260 io_uring/rw.c:120
io_import_rw_buffer io_uring/rw.c:139 [inline]
io_rw_do_import io_uring/rw.c:313 [inline]
io_prep_rw+0xb5/0x120 io_uring/rw.c:325
io_prep_rwv io_uring/rw.c:343 [inline]
io_prep_writev+0x23/0x80 io_uring/rw.c:363
io_init_req io_uring/io_uring.c:2235 [inline]
io_submit_sqe io_uring/io_uring.c:2282 [inline]
io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2435
__do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3285
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
BUG: memory leak
unreferenced object 0xffff888122889480 (size 32):
comm "syz.6.23", pid 6169, jiffies 4294942659
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................
backtrace (crc ccaa009e):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4958 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
__do_kmalloc_node mm/slub.c:5656 [inline]
__kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
kmalloc_array_noprof include/linux/slab.h:1003 [inline]
iovec_from_user lib/iov_iter.c:1321 [inline]
iovec_from_user+0x108/0x140 lib/iov_iter.c:1304
__import_iovec+0x71/0x350 lib/iov_iter.c:1375
io_import_vec io_uring/rw.c:99 [inline]
__io_import_rw_buffer+0x1e2/0x260 io_uring/rw.c:120
io_import_rw_buffer io_uring/rw.c:139 [inline]
io_rw_do_import io_uring/rw.c:313 [inline]
io_prep_rw+0xb5/0x120 io_uring/rw.c:325
io_prep_rwv io_uring/rw.c:343 [inline]
io_prep_writev+0x23/0x80 io_uring/rw.c:363
io_init_req io_uring/io_uring.c:2235 [inline]
io_submit_sqe io_uring/io_uring.c:2282 [inline]
io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2435
__do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3285
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF
---
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If the report is already addressed, let syzbot know by replying with:
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next reply other threads:[~2026-01-18 18:41 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-18 18:41 syzbot [this message]
2026-01-18 18:44 ` [syzbot] [io-uring?] memory leak in iovec_from_user (5) Jens Axboe
2026-01-20 15:24 ` Aleksandr Nogikh
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