linux-kernel - [PATCH] clkdev: only fall through to clk_get

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 26 Apr 2014 16:49:52 +0100
From:	Russell King <rmk+kernel@....linux.org.uk>
To:	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Cc:	Grant Likely <grant.likely@...aro.org>,
	Rob Herring <robh+dt@...nel.org>
Subject: [PATCH] clkdev: only fall through to clk_get_sys() if DT indicates no
 entry

There are two failures which DT can return when looking up a phandle:
-ENOENT - when DT finds that the desired property/index is not present
-EINVAL - when DT finds that the desired property/index is present, but
 there is a problem parsing it.

We should only fall through to clk_get_sys() (the table driven clock
lookup) when DT indicates that there was no entry in the OF tables
for the clock.  Doing otherwise causes the clk API to always indicate
that there is no entry for this clock, which is not correct behaviour.

Cc: <stable@...r.kernel.org>
Signed-off-by: Russell King <rmk+kernel@....linux.org.uk>
---
Grant, Rob,

Please let me know ASAP if this gives you any cause for concern.  This
looks to me like a long standing bug which really needs fixing.  Part
of the motivation here is similar to Jean-Francois' patch to clkdev
which allows a DT specified clock which isn't get present to have
clk_get() and friends return -EPROBE_DEFER - again, something that I
think really should happen.  Jean-Francois hasn't been able to get
much traction for his patch, so let's start with fixing this bug first.

 drivers/clk/clkdev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index 48f67218247c..4e65d0e10b05 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -165,7 +165,7 @@ struct clk *clk_get(struct device *dev, const char *con_id)

 	if (dev) {
 		clk = of_clk_get_by_name(dev->of_node, con_id);
-		if (!IS_ERR(clk))
+		if (!IS_ERR(clk) || PTR_ERR(clk) != -ENOENT)
 			return clk;
 	}

-- 
1.8.3.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/