diff options
| author | Shuah Khan <skhan@linuxfoundation.org> | 2021-07-07 18:28:40 -0600 |
|---|---|---|
| committer | Shuah Khan <skhan@linuxfoundation.org> | 2021-07-07 20:58:22 -0600 |
| commit | 642ca7e0c0a65486ff9ac3b2c42bfb113ee7c942 (patch) | |
| tree | 762fb5eed8943ead7699e2e89d59471d0cd0eb51 | |
| parent | 62fb9874f5da54fdb243003b386128037319b219 (diff) | |
| download | linux-bugs.tar.gz | |
firmware_loader: Fix use-after-free Read in firmware_loading_storebugs
If user writes to 'loading' between loading aborted and 'loading'
gets removed, __fw_load_abort() could be called twice in error
path setting the state to load aborted. __fw_load_abort() checks
for fw_sysfs_done() case, but doesn't check for abort case. This
opens the window for use-after-free Read in firmware_loading_store().
Fix it by adding check for fw load aborted in addition to done in
__fw_load_abort() and return if either one of the states is true.
BUG: KASAN: use-after-free in __list_del_entry_valid+0xd6/0xf0 lib/list_debug.c:54
Read of size 8 at addr ffff88802b3da2c8 by task systemd-udevd/25252
CPU: 0 PID: 25252 Comm: systemd-udevd Not tainted 5.13.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x141/0x1d7 lib/dump_stack.c:120
print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:233
__kasan_report mm/kasan/report.c:419 [inline]
kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:436
__list_del_entry_valid+0xd6/0xf0 lib/list_debug.c:54
__list_del_entry include/linux/list.h:132 [inline]
list_del_init include/linux/list.h:204 [inline]
__fw_load_abort drivers/base/firmware_loader/fallback.c:97 [inline]
__fw_load_abort drivers/base/firmware_loader/fallback.c:88 [inline]
fw_load_abort drivers/base/firmware_loader/fallback.c:105 [inline]
firmware_loading_store+0x141/0x650 drivers/base/firmware_loader/fallback.c:297
dev_attr_store+0x50/0x80 drivers/base/core.c:2066
sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:139
kernfs_fop_write_iter+0x342/0x500 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2114 [inline]
new_sync_write+0x426/0x650 fs/read_write.c:518
vfs_write+0x796/0xa30 fs/read_write.c:605
ksys_write+0x12d/0x250 fs/read_write.c:658
do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f6d0b3fe970
Code: 73 01 c3 48 8b 0d 28 d5 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 99 2d 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 7e 9b 01 00 48 89 04 24
RSP: 002b:00007ffde8a82ba8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f6d0b3fe970
RDX: 0000000000000002 RSI: 00005567e595b380 RDI: 0000000000000007
RBP: 00005567e595b380 R08: 00007f6d0c58c8c0 R09: 0000000000000002
R10: 0000000000000020 R11: 0000000000000246 R12: 0000000000000002
R13: 0000000000000001 R14: 00005567e59427d0 R15: 0000000000000002
Reported-by: syzbot+77cea49e091776a57689@syzkaller.appspotmail.com
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
| -rw-r--r-- | drivers/base/firmware_loader/fallback.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 91899d185e3110..e6a18c2a6c43d1 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -89,9 +89,10 @@ static void __fw_load_abort(struct fw_priv *fw_priv) { /* * There is a small window in which user can write to 'loading' - * between loading done and disappearance of 'loading' + * between loading done or aborted and disappearance of + * 'loading' */ - if (fw_sysfs_done(fw_priv)) + if (fw_sysfs_done(fw_priv) || fw_state_is_aborted(fw_priv)) return; list_del_init(&fw_priv->pending_list); |