syzbot


memory leak in prepare_creds (6)

Status: upstream: reported C repro on 2026/01/24 04:11
Subsystems: lsm input usb
[Documentation on labels]
Reported-by: syzbot+dd3b43aa0204089217ee@syzkaller.appspotmail.com
First crash: 4d04h, last: 4d04h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [lsm?] [input?] [usb?] memory leak in prepare_creds (6) 0 (1) 2026/01/24 04:11
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream memory leak in prepare_creds (3) lsm 3 C 24 1097d 1375d 0/29 auto-obsoleted due to no activity on 2023/05/24 05:02
upstream memory leak in prepare_creds (2) lsm 3 C 2 1676d 1771d 20/29 fixed on 2021/11/10 00:50
upstream memory leak in prepare_creds (5) lsm 3 C 60 6d04h 79d 29/29 fixed on 2026/01/21 09:45
upstream memory leak in prepare_creds (4) lsm 3 C 5 750d 849d 0/29 auto-obsoleted due to no activity on 2024/04/17 09:09
upstream memory leak in prepare_creds lsm 3 C 10 1802d 1977d 19/29 fixed on 2021/03/10 01:48
Last patch testing requests (1)
Created Duration User Patch Repo Result
2026/01/24 03:26 26m kuniyu@google.com patch upstream OK log

Sample crash report:
BUG: memory leak
unreferenced object 0xffff888108b89480 (size 184):
  comm "syz-executor", pid 5994, jiffies 4294943386
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc 369454a7):
    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]
    kmem_cache_alloc_noprof+0x412/0x580 mm/slub.c:5270
    prepare_creds+0x22/0x600 kernel/cred.c:185
    copy_creds+0x44/0x290 kernel/cred.c:286
    copy_process+0x7a7/0x2870 kernel/fork.c:2086
    kernel_clone+0xac/0x6e0 kernel/fork.c:2651
    __do_sys_clone+0x7f/0xb0 kernel/fork.c:2792
    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 0xffff8881032ee1a0 (size 32):
  comm "syz-executor", pid 5994, jiffies 4294943386
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    f8 52 86 00 81 88 ff ff 00 00 00 00 00 00 00 00  .R..............
  backtrace (crc 336e1c5f):
    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+0x465/0x680 mm/slub.c:5669
    kmalloc_noprof include/linux/slab.h:961 [inline]
    kzalloc_noprof include/linux/slab.h:1094 [inline]
    lsm_blob_alloc+0x4d/0x80 security/security.c:192
    lsm_cred_alloc security/security.c:209 [inline]
    security_prepare_creds+0x2d/0x290 security/security.c:2763
    prepare_creds+0x395/0x600 kernel/cred.c:215
    copy_creds+0x44/0x290 kernel/cred.c:286
    copy_process+0x7a7/0x2870 kernel/fork.c:2086
    kernel_clone+0xac/0x6e0 kernel/fork.c:2651
    __do_sys_clone+0x7f/0xb0 kernel/fork.c:2792
    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 0xffff888108b89540 (size 184):
  comm "syz-executor", pid 5994, jiffies 4294943447
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc 17b2a574):
    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]
    kmem_cache_alloc_noprof+0x412/0x580 mm/slub.c:5270
    prepare_creds+0x22/0x600 kernel/cred.c:185
    copy_creds+0x44/0x290 kernel/cred.c:286
    copy_process+0x7a7/0x2870 kernel/fork.c:2086
    kernel_clone+0xac/0x6e0 kernel/fork.c:2651
    __do_sys_clone+0x7f/0xb0 kernel/fork.c:2792
    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 0xffff8881032eee80 (size 32):
  comm "syz-executor", pid 5994, jiffies 4294943447
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    f8 52 86 00 81 88 ff ff 00 00 00 00 00 00 00 00  .R..............
  backtrace (crc 336e1c5f):
    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+0x465/0x680 mm/slub.c:5669
    kmalloc_noprof include/linux/slab.h:961 [inline]
    kzalloc_noprof include/linux/slab.h:1094 [inline]
    lsm_blob_alloc+0x4d/0x80 security/security.c:192
    lsm_cred_alloc security/security.c:209 [inline]
    security_prepare_creds+0x2d/0x290 security/security.c:2763
    prepare_creds+0x395/0x600 kernel/cred.c:215
    copy_creds+0x44/0x290 kernel/cred.c:286
    copy_process+0x7a7/0x2870 kernel/fork.c:2086
    kernel_clone+0xac/0x6e0 kernel/fork.c:2651
    __do_sys_clone+0x7f/0xb0 kernel/fork.c:2792
    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 0xffff888109bf16c0 (size 184):
  comm "syz-executor", pid 5994, jiffies 4294943507
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc a1f2f9ed):
    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]
    kmem_cache_alloc_noprof+0x412/0x580 mm/slub.c:5270
    prepare_creds+0x22/0x600 kernel/cred.c:185
    copy_creds+0x44/0x290 kernel/cred.c:286
    copy_process+0x7a7/0x2870 kernel/fork.c:2086
    kernel_clone+0xac/0x6e0 kernel/fork.c:2651
    __do_sys_clone+0x7f/0xb0 kernel/fork.c:2792
    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 0xffff888109151e00 (size 32):
  comm "syz-executor", pid 5994, jiffies 4294943507
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    f8 52 86 00 81 88 ff ff 00 00 00 00 00 00 00 00  .R..............
  backtrace (crc 336e1c5f):
    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+0x465/0x680 mm/slub.c:5669
    kmalloc_noprof include/linux/slab.h:961 [inline]
    kzalloc_noprof include/linux/slab.h:1094 [inline]
    lsm_blob_alloc+0x4d/0x80 security/security.c:192
    lsm_cred_alloc security/security.c:209 [inline]
    security_prepare_creds+0x2d/0x290 security/security.c:2763
    prepare_creds+0x395/0x600 kernel/cred.c:215
    copy_creds+0x44/0x290 kernel/cred.c:286
    copy_process+0x7a7/0x2870 kernel/fork.c:2086
    kernel_clone+0xac/0x6e0 kernel/fork.c:2651
    __do_sys_clone+0x7f/0xb0 kernel/fork.c:2792
    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

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/21 22:05 upstream 6c790212c588 6f1aa2f9 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-leak memory leak in prepare_creds
* Struck through repros no longer work on HEAD.