diff options
| author | Yuran Pereira | 2023-11-08 02:18:36 +0530 |
|---|---|---|
| committer | David S. Miller | 2023-11-10 08:35:59 +0000 |
| commit | 8a4f030dbced6fc255cbe67b2d0a129947e18493 (patch) | |
| tree | b7326f8ff16fe0a1cb1f5df376fe026824ae0577 /drivers/ptp | |
| parent | 89cdf9d556016a54ff6ddd62324aa5ec790c05cc (diff) | |
ptp: Fixes a null pointer dereference in ptp_ioctl
Syzkaller found a null pointer dereference in ptp_ioctl
originating from the lack of a null check for tsevq.
```
general protection fault, probably for non-canonical
address 0xdffffc000000020b: 0000 [#1] PREEMPT SMP KASAN
KASAN: probably user-memory-access in range
[0x0000000000001058-0x000000000000105f]
CPU: 0 PID: 5053 Comm: syz-executor353 Not tainted
6.6.0-syzkaller-10396-g4652b8e4f3ff #0
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 10/09/2023
RIP: 0010:ptp_ioctl+0xcb7/0x1d10 drivers/ptp/ptp_chardev.c:476
...
Call Trace:
<TASK>
posix_clock_ioctl+0xf8/0x160 kernel/time/posix-clock.c:86
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
```
This patch fixes the issue by adding a check for tsevq and
ensuring ptp_ioctl returns with an error if tsevq is null.
Reported-by: syzbot+8a78ecea7ac1a2ea26e5@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=8a78ecea7ac1a2ea26e5
Fixes: c5a445b1e934 ("ptp: support event queue reader channel masks")
Signed-off-by: Yuran Pereira <yuran.pereira@hotmail.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/ptp')
| -rw-r--r-- | drivers/ptp/ptp_chardev.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c index 3f7a74788802..e95a6ed130ef 100644 --- a/drivers/ptp/ptp_chardev.c +++ b/drivers/ptp/ptp_chardev.c @@ -176,6 +176,8 @@ long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd, int enable, err = 0; tsevq = pccontext->private_clkdata; + if (!tsevq) + return -EINVAL; switch (cmd) { |