From: Zhou Qingyang zhou1615@umn.edu
[ Upstream commit 8dbdcc7269a83305ee9d677b75064d3530a48ee2 ]
In dib8000_init(), the variable fe is not freed or passed out on the failure of dib8000_identify(&state->i2c), which could lead to a memleak.
Fix this bug by adding a kfree of fe in the error path.
This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug.
Builds with CONFIG_DVB_DIB8000=m show no new warnings, and our static analyzer no longer warns about this code.
Fixes: 77e2c0f5d471 ("V4L/DVB (12900): DiB8000: added support for DiBcom ISDB-T/ISDB-Tsb demodulator DiB8000") Signed-off-by: Zhou Qingyang zhou1615@umn.edu Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/dvb-frontends/dib8000.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/media/dvb-frontends/dib8000.c b/drivers/media/dvb-frontends/dib8000.c index 5fa787e023c7e..4b9e4afa4c61f 100644 --- a/drivers/media/dvb-frontends/dib8000.c +++ b/drivers/media/dvb-frontends/dib8000.c @@ -4476,8 +4476,10 @@ static struct dvb_frontend *dib8000_init(struct i2c_adapter *i2c_adap, u8 i2c_ad
state->timf_default = cfg->pll->timf;
- if (dib8000_identify(&state->i2c) == 0) + if (dib8000_identify(&state->i2c) == 0) { + kfree(fe); goto error; + }
dibx000_init_i2c_master(&state->i2c_master, DIB8000, state->i2c.adap, state->i2c.addr);