On 2022/01/07 21:53, Jiasheng Jiang wrote:

In linux-stable-5.15.13, this file has been removed and combined to `drivers/ata/pata_platform.c` without this bug. But in the older LTS kernels, like 5.10.90, this bug still exists. As the possible failure of the devres_alloc(), the devm_ioremap() and devm_ioport_map() may return NULL pointer. And then, the 'base' and 'alt_base' are used in plat_ide_setup_ports(). Therefore, it should be better to add the check in order to avoid the dereference of the NULL pointer. Actually, it introduced the bug from commit 8cb1f567f4c0 ("ide: Platform IDE driver") and we can know from the commit message that it tended to be similar to the `drivers/ata/pata_platform.c`. But actually, even the first time pata_platform was built, commit a20c9e820864 ("[PATCH] ata: Generic platform_device libata driver"), there was no the bug, as there was a check after the ioremap(). So possibly the bug was caused by ide itself.

Fixes: 8cb1f567f4c0 ("ide: Platform IDE driver") Cc: stable@vger.kernel.org#5.10

Please keep the space before the #

Cc: stable@vger.kernel.org #5.10

Signed-off-by: Jiasheng Jiang jiasheng@iscas.ac.cn

Changelog

v1 -> v2

• Change 1. Correct the fixes tag and commit message.

v2 -> v3

• Change 1. Correct the code.

As commented before, what exactly was corrected ? That is what needs to be mentioned here. In any case, I fail to see what code change you added between v2 and v3. The code changes are identical in the 2 versions.

---

drivers/ide/ide_platform.c | 4 ++++ 1 file changed, 4 insertions(+)

diff --git a/drivers/ide/ide_platform.c b/drivers/ide/ide_platform.c index 91639fd6c276..5500c5afb3ca 100644 --- a/drivers/ide/ide_platform.c +++ b/drivers/ide/ide_platform.c @@ -85,6 +85,10 @@ static int plat_ide_probe(struct platform_device *pdev) alt_base = devm_ioport_map(&pdev->dev, res_alt->start, resource_size(res_alt)); }

• if (!base || !alt_base) {

• ret = -ENOMEM;
  

• goto out;
  

• }

memset(&hw, 0, sizeof(hw)); plat_ide_setup_ports(&hw, base, alt_base, pdata, res_irq->start);

Greg,

The above patch is OK but cannot be applied in the current kernel: * The Legacy IDE drivers were removed in 5.14, replaced by the already existing * The current equivalent libata driver (drivers/ata/pata_platform.c) already has the above error check.

So I think this patch needs to go directly to stable # 5.10 and earlier LTS kernels. Can you take it ?

Feel free to add:

Acked-by: Damien Le Moal damien.lemoal@opensource.wdc.com

Note that I was not the maintainer of the IDE drivers. If more appropriate please feel free to replace that with a Reviewed-by tag.

Thanks !