syzbot


KASAN: null-ptr-deref Read in __free_pages

Status: upstream: reported C repro on 2022/03/20 22:04
Reported-by: syzbot+d55757faa9b80590767b@syzkaller.appspotmail.com
Fix commit: a635415a064e watch_queue: Fix NULL dereference in error cleanup
Patched on: [ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-leak ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce ci-upstream-kmsan-gce-386 ci-upstream-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu2-riscv64]
First crash: 104d, last: 42d

Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: KASAN: null-ptr-deref Read in __free_pages (log)
Repro: C syz .config
Patch testing requests:
Created Duration User Patch Repo Result
2022/03/21 11:20 8m dhowells@redhat.com git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git 733021c6d8607c5c5ab08bbe9b400d0da609185f OK
2022/03/21 08:24 9m dhowells@redhat.com git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git 6d39b096627f0a1eb6e14f049d8ae3c93e0290f2 OK
2022/03/21 00:28 8m fmdefrancesco@gmail.com patch upstream OK
2022/03/20 23:40 9m fmdefrancesco@gmail.com patch upstream report log
2022/03/20 23:33 4m fmdefrancesco@gmail.com patch upstream error

Sample crash report:
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc794ecea0 R14: 000000000000000d R15: 00007ff328525490
 </TASK>
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: null-ptr-deref in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
BUG: KASAN: null-ptr-deref in page_ref_count include/linux/page_ref.h:67 [inline]
BUG: KASAN: null-ptr-deref in put_page_testzero include/linux/mm.h:717 [inline]
BUG: KASAN: null-ptr-deref in __free_pages+0x1f/0x1b0 mm/page_alloc.c:5473
Read of size 4 at addr 0000000000000034 by task syz-executor168/3599

CPU: 1 PID: 3599 Comm: syz-executor168 Not tainted 5.17.0-rc8-syzkaller-00003-g56e337f2cf13 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 __kasan_report mm/kasan/report.c:446 [inline]
 kasan_report.cold+0x66/0xdf mm/kasan/report.c:459
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 page_ref_count include/linux/page_ref.h:67 [inline]
 put_page_testzero include/linux/mm.h:717 [inline]
 __free_pages+0x1f/0x1b0 mm/page_alloc.c:5473
 watch_queue_set_size+0x499/0x630 kernel/watch_queue.c:275
 pipe_ioctl+0xac/0x2b0 fs/pipe.c:632
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7ff3284b2d59
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 31 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc794ece38 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000031 RCX: 00007ff3284b2d59
RDX: 0000000000000029 RSI: 0000000000005760 RDI: 0000000000000003
RBP: 00007ffc794ece40 R08: 0000000000000001 R09: 00007ffc794e0035
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc794ecea0 R14: 000000000000000d R15: 00007ff328525490
 </TASK>
==================================================================

Crashes (17):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce 2022/03/16 22:15 upstream 56e337f2cf13 dfa9a8ed .config log report syz C KASAN: null-ptr-deref Read in __free_pages
ci-upstream-kasan-gce-selinux-root 2022/03/19 11:41 upstream 34e047aa16c0 e2d91b1d .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-upstream-kasan-gce-root 2022/03/16 22:15 upstream 56e337f2cf13 dfa9a8ed .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-upstream-kasan-gce 2022/03/16 22:01 upstream 56e337f2cf13 dfa9a8ed .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-qemu2-arm64 2022/03/19 18:06 upstream 34e047aa16c0 e2d91b1d .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-qemu2-arm64 2022/03/18 12:30 upstream 551acdc3c3d2 e2d91b1d .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-qemu2-arm64 2022/03/18 12:00 upstream 551acdc3c3d2 e2d91b1d .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-qemu2-riscv64 2022/05/17 13:07 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes 0966d385830d 744a39e2 .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-qemu2-riscv64 2022/03/27 21:57 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes 0966d385830d 89bc8608 .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-qemu2-riscv64 2022/03/21 03:20 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes 0966d385830d e2d91b1d .config log report info KASAN: null-ptr-deref Read in __free_pages
ci-qemu2-arm32 2022/03/19 13:32 upstream 34e047aa16c0 e2d91b1d .config log report info BUG: unable to handle kernel NULL pointer dereference in __free_pages
ci-qemu2-arm32 2022/03/19 06:25 upstream 34e047aa16c0 e2d91b1d .config log report info BUG: unable to handle kernel NULL pointer dereference in __free_pages
ci-qemu2-arm32 2022/03/18 04:52 upstream 551acdc3c3d2 e2d91b1d .config log report info BUG: unable to handle kernel NULL pointer dereference in __free_pages
ci-qemu2-arm32 2022/03/17 02:12 upstream 56e337f2cf13 46cc3b21 .config log report info BUG: unable to handle kernel NULL pointer dereference in __free_pages
ci-qemu2-arm32 2022/03/17 00:09 upstream 56e337f2cf13 46cc3b21 .config log report info BUG: unable to handle kernel NULL pointer dereference in __free_pages
ci-qemu2-arm32 2022/03/16 23:50 upstream 56e337f2cf13 46cc3b21 .config log report info BUG: unable to handle kernel NULL pointer dereference in __free_pages
ci-qemu2-arm32 2022/03/16 22:28 upstream 56e337f2cf13 46cc3b21 .config log report info BUG: unable to handle kernel NULL pointer dereference in __free_pages