[PATCH] twl-core: fix oops while calling twl_i2c_* for unbound driver

From: Ilya Yanok
Date: Mon Aug 01 2011 - 17:00:50 EST


Check inuse variable before trying to access twl_map to prevent
dereferencing of uninitialized variable.

Signed-off-by: Ilya Yanok <yanok@xxxxxxxxxxx>
---
drivers/mfd/twl-core.c | 16 ++++++++--------
1 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/mfd/twl-core.c b/drivers/mfd/twl-core.c
index 01ecfee..c7bc222 100644
--- a/drivers/mfd/twl-core.c
+++ b/drivers/mfd/twl-core.c
@@ -362,13 +362,13 @@ int twl_i2c_write(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
return -EPERM;
}
- sid = twl_map[mod_no].sid;
- twl = &twl_modules[sid];
-
if (unlikely(!inuse)) {
- pr_err("%s: client %d is not initialized\n", DRIVER_NAME, sid);
+ pr_err("%s: not initialized\n", DRIVER_NAME);
return -EPERM;
}
+ sid = twl_map[mod_no].sid;
+ twl = &twl_modules[sid];
+
mutex_lock(&twl->xfer_lock);
/*
* [MSG1]: fill the register address data
@@ -419,13 +419,13 @@ int twl_i2c_read(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
return -EPERM;
}
- sid = twl_map[mod_no].sid;
- twl = &twl_modules[sid];
-
if (unlikely(!inuse)) {
- pr_err("%s: client %d is not initialized\n", DRIVER_NAME, sid);
+ pr_err("%s: not initialized\n", DRIVER_NAME);
return -EPERM;
}
+ sid = twl_map[mod_no].sid;
+ twl = &twl_modules[sid];
+
mutex_lock(&twl->xfer_lock);
/* [MSG1] fill the register address data */
msg = &twl->xfer_msg[0];
--
1.7.6

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