From: Yang Yingliang yangyingliang@huawei.com

mainline inclusion from mainline-v5.15-rc7 commit 4225fea1cb28370086e17e82c0f69bec2779dca0 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9RBLZ CVE: CVE-2021-47455

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

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I got memory leak as follows when doing fault injection test:

unreferenced object 0xffff88800906c618 (size 8): comm "i2c-idt82p33931", pid 4421, jiffies 4294948083 (age 13.188s) hex dump (first 8 bytes): 70 74 70 30 00 00 00 00 ptp0.... backtrace: [<00000000312ed458>] __kmalloc_track_caller+0x19f/0x3a0 [<0000000079f6e2ff>] kvasprintf+0xb5/0x150 [<0000000026aae54f>] kvasprintf_const+0x60/0x190 [<00000000f323a5f7>] kobject_set_name_vargs+0x56/0x150 [<000000004e35abdd>] dev_set_name+0xc0/0x100 [<00000000f20cfe25>] ptp_clock_register+0x9f4/0xd30 [ptp] [<000000008bb9f0de>] idt82p33_probe.cold+0x8b6/0x1561 [ptp_idt82p33]

When posix_clock_register() returns an error, the name allocated in dev_set_name() will be leaked, the put_device() should be used to give up the device reference, then the name will be freed in kobject_cleanup() and other memory will be freed in ptp_clock_release().

Reported-by: Hulk Robot hulkci@huawei.com Fixes: a33121e5487b ("ptp: fix the race between the release of ptp_clock and cdev") Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: David S. Miller davem@davemloft.net Conflicts: drivers/ptp/ptp_clock.c ['ptp->vclock_index' is introduced since commit 44c494c8e30e ("ptp: track available ptp vclocks information"), so drop the code `kfree(ptp->vclock_index);`] Signed-off-by: Zheng Yejian zhengyejian1@huawei.com --- drivers/ptp/ptp_clock.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index ed766943a356..bf583f497357 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -274,15 +274,20 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, /* Create a posix clock and link it to the device. */ err = posix_clock_register(&ptp->clock, &ptp->dev); if (err) { + if (ptp->pps_source) + pps_unregister_source(ptp->pps_source); + + if (ptp->kworker) + kthread_destroy_worker(ptp->kworker); + + put_device(&ptp->dev); + pr_err("failed to create posix clock\n"); - goto no_clock; + return ERR_PTR(err); }

return ptp;

-no_clock: - if (ptp->pps_source) - pps_unregister_source(ptp->pps_source); no_pps: ptp_cleanup_pin_groups(ptp); no_pin_groups: