* [PATCH] ufs: qcom: Properly clear hba priv on failure @ 2016-11-18 20:55 Bjorn Andersson 2016-11-19 20:30 ` Subhash Jadavani 0 siblings, 1 reply; 4+ messages in thread From: Bjorn Andersson @ 2016-11-18 20:55 UTC (permalink / raw) To: Vinayak Holikatti, James E.J. Bottomley, Martin K. Petersen Cc: Yaniv Gardi, Vivek Gautam, linux-scsi, linux-kernel, linux-arm-msm In the case where we fail to acquire the phy the hba priv will be set already, so during cleanup ufs_qcom_setup_clocks() will dereference the now free, but still "valid looking" pointer "host". Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> --- drivers/scsi/ufs/ufs-qcom.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c index d345434b084f..7bd88ffee47a 100644 --- a/drivers/scsi/ufs/ufs-qcom.c +++ b/drivers/scsi/ufs/ufs-qcom.c @@ -1197,7 +1197,7 @@ static int ufs_qcom_init(struct ufs_hba *hba) if (IS_ERR(host->generic_phy)) { err = PTR_ERR(host->generic_phy); dev_err(dev, "%s: PHY get failed %d\n", __func__, err); - goto out; + goto out_host_free; } err = ufs_qcom_bus_register(host); -- 2.5.0 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] ufs: qcom: Properly clear hba priv on failure 2016-11-18 20:55 [PATCH] ufs: qcom: Properly clear hba priv on failure Bjorn Andersson @ 2016-11-19 20:30 ` Subhash Jadavani 2016-11-20 6:15 ` Bjorn Andersson 0 siblings, 1 reply; 4+ messages in thread From: Subhash Jadavani @ 2016-11-19 20:30 UTC (permalink / raw) To: Bjorn Andersson Cc: Vinayak Holikatti, James E.J. Bottomley, Martin K. Petersen, Yaniv Gardi, Vivek Gautam, linux-scsi, linux-kernel, linux-arm-msm, linux-scsi-owner On 2016-11-18 12:55, Bjorn Andersson wrote: > In the case where we fail to acquire the phy the hba priv will be set > already, so during cleanup ufs_qcom_setup_clocks() will dereference the > now free, but still "valid looking" pointer "host". host (ufs_qcom_host) was allocated with devm_kzalloc() so i am not sure why it would be freed up before probe() returns failure. > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > --- > drivers/scsi/ufs/ufs-qcom.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c > index d345434b084f..7bd88ffee47a 100644 > --- a/drivers/scsi/ufs/ufs-qcom.c > +++ b/drivers/scsi/ufs/ufs-qcom.c > @@ -1197,7 +1197,7 @@ static int ufs_qcom_init(struct ufs_hba *hba) > if (IS_ERR(host->generic_phy)) { > err = PTR_ERR(host->generic_phy); > dev_err(dev, "%s: PHY get failed %d\n", __func__, err); > - goto out; > + goto out_host_free; > } > > err = ufs_qcom_bus_register(host); -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] ufs: qcom: Properly clear hba priv on failure 2016-11-19 20:30 ` Subhash Jadavani @ 2016-11-20 6:15 ` Bjorn Andersson 2016-11-21 18:32 ` Subhash Jadavani 0 siblings, 1 reply; 4+ messages in thread From: Bjorn Andersson @ 2016-11-20 6:15 UTC (permalink / raw) To: Subhash Jadavani Cc: Vinayak Holikatti, James E.J. Bottomley, Martin K. Petersen, Yaniv Gardi, Vivek Gautam, linux-scsi, linux-kernel, linux-arm-msm, linux-scsi-owner On Sat 19 Nov 12:30 PST 2016, Subhash Jadavani wrote: > On 2016-11-18 12:55, Bjorn Andersson wrote: > >In the case where we fail to acquire the phy the hba priv will be set > >already, so during cleanup ufs_qcom_setup_clocks() will dereference the > >now free, but still "valid looking" pointer "host". > > host (ufs_qcom_host) was allocated with devm_kzalloc() so i am not sure why > it would be freed up before probe() returns failure. > Sorry, I missed the fact that the devm_kfree() was dropped, the actual problem still remains, although it no longer results in a panic. As ufs_qcom_init() returns from not having found the phy it the variant data will be a zero-initialized object. The error path of ufshcd_hba_init() will then take us through ufs_qcom_setup_clocks(), which will pass the check for a NULL variant data and use the uninitialized host object. I can update the commit message to reflect the new state of things. Regards, Bjorn > >Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > >--- > > drivers/scsi/ufs/ufs-qcom.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > >diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c > >index d345434b084f..7bd88ffee47a 100644 > >--- a/drivers/scsi/ufs/ufs-qcom.c > >+++ b/drivers/scsi/ufs/ufs-qcom.c > >@@ -1197,7 +1197,7 @@ static int ufs_qcom_init(struct ufs_hba *hba) > > if (IS_ERR(host->generic_phy)) { > > err = PTR_ERR(host->generic_phy); > > dev_err(dev, "%s: PHY get failed %d\n", __func__, err); > >- goto out; > >+ goto out_host_free; > > } > > > > err = ufs_qcom_bus_register(host); > > -- > The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, > a Linux Foundation Collaborative Project ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] ufs: qcom: Properly clear hba priv on failure 2016-11-20 6:15 ` Bjorn Andersson @ 2016-11-21 18:32 ` Subhash Jadavani 0 siblings, 0 replies; 4+ messages in thread From: Subhash Jadavani @ 2016-11-21 18:32 UTC (permalink / raw) To: Bjorn Andersson Cc: Vinayak Holikatti, James E.J. Bottomley, Martin K. Petersen, Yaniv Gardi, Vivek Gautam, linux-scsi, linux-kernel, linux-arm-msm, linux-scsi-owner On 2016-11-19 22:15, Bjorn Andersson wrote: > On Sat 19 Nov 12:30 PST 2016, Subhash Jadavani wrote: > >> On 2016-11-18 12:55, Bjorn Andersson wrote: >> >In the case where we fail to acquire the phy the hba priv will be set >> >already, so during cleanup ufs_qcom_setup_clocks() will dereference the >> >now free, but still "valid looking" pointer "host". >> >> host (ufs_qcom_host) was allocated with devm_kzalloc() so i am not >> sure why >> it would be freed up before probe() returns failure. >> > > Sorry, I missed the fact that the devm_kfree() was dropped, the actual > problem still remains, although it no longer results in a panic. Agreed. > > As ufs_qcom_init() returns from not having found the phy it the variant > data will be a zero-initialized object. The error path of > ufshcd_hba_init() will then take us through ufs_qcom_setup_clocks(), > which will pass the check for a NULL variant data and use the > uninitialized host object. Yes, Make sense. > > I can update the commit message to reflect the new state of things. Your new patch set looks good, will add my ack. > > Regards, > Bjorn > >> >Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> >> >--- >> > drivers/scsi/ufs/ufs-qcom.c | 2 +- >> > 1 file changed, 1 insertion(+), 1 deletion(-) >> > >> >diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c >> >index d345434b084f..7bd88ffee47a 100644 >> >--- a/drivers/scsi/ufs/ufs-qcom.c >> >+++ b/drivers/scsi/ufs/ufs-qcom.c >> >@@ -1197,7 +1197,7 @@ static int ufs_qcom_init(struct ufs_hba *hba) >> > if (IS_ERR(host->generic_phy)) { >> > err = PTR_ERR(host->generic_phy); >> > dev_err(dev, "%s: PHY get failed %d\n", __func__, err); >> >- goto out; >> >+ goto out_host_free; >> > } >> > >> > err = ufs_qcom_bus_register(host); >> >> -- >> The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, >> a Linux Foundation Collaborative Project > -- > To unsubscribe from this list: send the line "unsubscribe linux-scsi" > in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2016-11-21 18:32 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2016-11-18 20:55 [PATCH] ufs: qcom: Properly clear hba priv on failure Bjorn Andersson 2016-11-19 20:30 ` Subhash Jadavani 2016-11-20 6:15 ` Bjorn Andersson 2016-11-21 18:32 ` Subhash Jadavani
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