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Wysocki" , Danilo Krummrich , Jonathan Cameron , Alison Schofield , Yury Norov , Dave Jiang , KAMEZAWA Hiroyuki References: <20250917134604.2149316-1-clm@meta.com> Content-Language: en-US From: Donet Tom In-Reply-To: <20250917134604.2149316-1-clm@meta.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: wA33Ic2Fwwy0CtaNYj3S3UXMkwZMpURl X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwOTE2MDIwNCBTYWx0ZWRfX8X65/ufRsGVo bDCC1dccNXM0EWET9nYDeBvXFOX+osCHHAFBagTCHm/nXv88A/WHoQGYfDDSJPHh6iUGiqByniK +Ps8jp+GPtn3Xlu318ZUmH9rZiXD6BRqERZDWz/JLpdHd4oxCxqN6zGWmPxnlWYEbbq03gw6lTS +FDJXupWDT/2BakFtzHXEVPFMuqWOTiXsaLJ6o5Ai2iZpP8aHeSnktedd2SEN2rqVw7q1Su/dup wn7Y0HRnt0UD9vX8e7XWpmFQ407ic2GoO0Clnmjh1KK9aG3/kNQAr1J99sh5R2qTiVbMM57JiGx fE9xNOS5gUBJfpnUNGkBw1+NN8uOO+GnKiFitv97Z4pDWeX92o9YnbAHCPAYf0O2njuJC1FKeX4 1sBNEDUh X-Authority-Analysis: v=2.4 cv=R8oDGcRX c=1 sm=1 tr=0 ts=68cacbfd cx=c_pps a=5BHTudwdYE3Te8bg5FgnPg==:117 a=5BHTudwdYE3Te8bg5FgnPg==:17 a=IkcTkHD0fZMA:10 a=yJojWOMRYYMA:10 a=VwQbUJbxAAAA:8 a=VnNF1IyMAAAA:8 a=rKeXGq08CVa402lCTmoA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: EX0LyWaAr9H_o1C6qQrgirVdE316IUWH X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1117,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-09-17_01,2025-09-17_02,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1011 suspectscore=0 malwarescore=0 bulkscore=0 spamscore=0 adultscore=0 impostorscore=0 priorityscore=1501 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2507300000 definitions=main-2509160204 On 9/17/25 7:15 PM, Chris Mason wrote: > On Fri, 22 Aug 2025 14:18:45 +0530 Donet Tom wrote: > >> If register_node() returns an error, it is not handled correctly. >> The function will proceed further and try to register CPUs under the >> node, which is not correct. >> >> So, in this patch, if register_node() returns an error, we return >> immediately from the function. >> >> Fixes: 76b67ed9dce6 ("[PATCH] node hotplug: register cpu: remove node struct") >> Signed-off-by: Donet Tom >> --- >> v1 -> v2 >> Made the changes based on Oscar’s review comments. >> >> v1 - https://lore.kernel.org/all/20250702112856.295176-1-donettom@linux.ibm.com/ >> --- >> drivers/base/node.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/drivers/base/node.c b/drivers/base/node.c >> index c65b4917794e..1608816de67f 100644 >> --- a/drivers/base/node.c >> +++ b/drivers/base/node.c >> @@ -883,6 +883,11 @@ int register_one_node(int nid) >> node_devices[nid] = node; >> >> error = register_node(node_devices[nid], nid); >> + if (error) { >> + node_devices[nid] = NULL; >> + kfree(node); >> + return error; >> + } > Can this cause a double-free? Looking at register_node(), when > device_register() fails, it calls put_device(&node->dev). The put_device() > call triggers node_device_release() which does kfree(to_node(dev)), freeing > the entire node structure. So when register_node() returns an error, the > node memory is already freed, but this code calls kfree(node) again on the > same memory. > > The call chain is: register_node()->device_register() fails-> > put_device()->node_device_release()->kfree(to_node(dev)). Thank you for pointing this out. I will address it and send a v3. > > [ This came from automated patch review, but it looks real to me ] > > -chris >