diff options
| author | Edward Adam Davis <eadavis@qq.com> | 2023-11-07 09:00:41 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-11-09 03:47:07 +0100 |
| commit | 1bea2c3e6df8caf45d18384abfb707f47e9ff993 (patch) | |
| tree | 247a0999ede72aabbdd2c4acf9ada9a843947ebd /drivers/ptp/ptp_chardev.c | |
| parent | ptp: ptp_read should not release queue (diff) | |
| download | linux-1bea2c3e6df8caf45d18384abfb707f47e9ff993.tar.xz linux-1bea2c3e6df8caf45d18384abfb707f47e9ff993.zip | |
ptp: fix corrupted list in ptp_open
There is no lock protection when writing ptp->tsevqs in ptp_open() and
ptp_release(), which can cause data corruption, use spin lock to avoid this
issue.
Moreover, ptp_release() should not be used to release the queue in ptp_read(),
and it should be deleted altogether.
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reported-and-tested-by: syzbot+df3f3ef31f60781fa911@syzkaller.appspotmail.com
Fixes: 8f5de6fb2453 ("ptp: support multiple timestamp event readers")
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Link: https://lore.kernel.org/r/tencent_CD19564FFE8DA8A5918DFE92325D92DD8107@qq.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/ptp/ptp_chardev.c')
| -rw-r--r-- | drivers/ptp/ptp_chardev.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c index 27c1ef493617..3f7a74788802 100644 --- a/drivers/ptp/ptp_chardev.c +++ b/drivers/ptp/ptp_chardev.c @@ -108,6 +108,7 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode) container_of(pccontext->clk, struct ptp_clock, clock); struct timestamp_event_queue *queue; char debugfsname[32]; + unsigned long flags; queue = kzalloc(sizeof(*queue), GFP_KERNEL); if (!queue) @@ -119,7 +120,9 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode) } bitmap_set(queue->mask, 0, PTP_MAX_CHANNELS); spin_lock_init(&queue->lock); + spin_lock_irqsave(&ptp->tsevqs_lock, flags); list_add_tail(&queue->qlist, &ptp->tsevqs); + spin_unlock_irqrestore(&ptp->tsevqs_lock, flags); pccontext->private_clkdata = queue; /* Debugfs contents */ @@ -139,16 +142,16 @@ int ptp_release(struct posix_clock_context *pccontext) { struct timestamp_event_queue *queue = pccontext->private_clkdata; unsigned long flags; + struct ptp_clock *ptp = + container_of(pccontext->clk, struct ptp_clock, clock); - if (queue) { - debugfs_remove(queue->debugfs_instance); - pccontext->private_clkdata = NULL; - spin_lock_irqsave(&queue->lock, flags); - list_del(&queue->qlist); - spin_unlock_irqrestore(&queue->lock, flags); - bitmap_free(queue->mask); - kfree(queue); - } + debugfs_remove(queue->debugfs_instance); + pccontext->private_clkdata = NULL; + spin_lock_irqsave(&ptp->tsevqs_lock, flags); + list_del(&queue->qlist); + spin_unlock_irqrestore(&ptp->tsevqs_lock, flags); + bitmap_free(queue->mask); + kfree(queue); return 0; } |