On Thu, Aug 22, 2024 at 11:30:50AM +0800, Zheng Qixing wrote: > From: Zheng Qixing <zhengqixing@xxxxxxxxxx> > > In ata_host_alloc(), if ata_port_alloc(host) fails to allocate memory > for a port, the allocated 'host' structure is not freed before returning > from the function. This results in a potential memory leak. This sentence is wrong. If ata_port_alloc() fails, we must have already called devres_alloc(ata_devres_release, ...); which means that when: ap = ata_port_alloc(host); if (!ap) goto err_out; ... err_out: devres_release_group(dev, NULL); return NULL; devres_release_group() will trigger a call to ata_host_release(). ata_host_release() calls kfree(host). So we will not leak "host" if ata_port_alloc() fails. > > This patch adds a kfree(host) before the error handling code is executed > to ensure that the 'host' structure is properly freed in case of an > allocation failure. > > Signed-off-by: Zheng Qixing <zhengqixing@xxxxxxxxxx> > --- > Changes in v2: > - error path is wrong in v1 > > drivers/ata/libata-core.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c > index e4023fc288ac..f27a18990c38 100644 > --- a/drivers/ata/libata-core.c > +++ b/drivers/ata/libata-core.c > @@ -5663,8 +5663,10 @@ struct ata_host *ata_host_alloc(struct device *dev, int n_ports) > } > > dr = devres_alloc(ata_devres_release, 0, GFP_KERNEL); > - if (!dr) > + if (!dr) { > + kfree(host); > goto err_out; This code does free "host" if devres_alloc() fails, which looks correct, as "host" will currently be leaked if devres_alloc() fails. However, that is not what the commit log above claims :P Please update the commit message to reflect reality. Kind regards, Niklas