On 2019/12/29 4:45, Markus Elfring wrote:

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v3d_submit_cl_ioctl call kfree() with variable 'bin' twice.

I would prefer a wording like “kfree() was called for the same variable twice within an if branch.”.

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Fix it by removing the latter one.

I find the wording “Delete a duplicate function call.” more appropriate.

Thank you for your advise, I'll make changes in V2 patch.

Please add the tag “Fixes” to your change description.

I got the results from "git blame": git blame -L 570,575 drivers/gpu/drm/v3d/v3d_gem.c a783a09ee76d6 (Eric Anholt 2019-04-16 15:58:53 -0700 570) if (ret) { 0d352a3a8a1f2 (Iago Toral Quiroga 2019-09-16 09:11:25 +0200 571) kfree(bin); a783a09ee76d6 (Eric Anholt 2019-04-16 15:58:53 -0700 572) v3d_job_put(&render->base); 29cd13cfd7624 (Navid Emamdoost 2019-10-21 13:52:49 -0500 573) kfree(bin); a783a09ee76d6 (Eric Anholt 2019-04-16 15:58:53 -0700 574) return ret; a783a09ee76d6 (Eric Anholt 2019-04-16 15:58:53 -0700 575) }

The first kfree belong to the patch 0d352a3a8a1f2 : commit 0d352a3a8a1f26168d09f7073e61bb4b328e3bb9 Author: Iago Toral Quiroga itoral@igalia.com Date: Mon Sep 16 09:11:25 2019 +0200

drm/v3d: don't leak bin job if v3d_job_init fails.

If the initialization of the job fails we need to kfree() it before returning.

Signed-off-by: Iago Toral Quiroga itoral@igalia.com Signed-off-by: Eric Anholt eric@anholt.net Link: https://patchwork.freedesktop.org/patch/msgid/20190916071125.5255-1-itoral@i... Fixes: a783a09ee76d ("drm/v3d: Refactor job management.") Reviewed-by: Eric Anholt eric@anholt.net

diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index 5d80507b539b..fb32cda18ffe 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -563,6 +563,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, ret = v3d_job_init(v3d, file_priv, &bin->base, v3d_job_free, args->in_sync_bcl); if (ret) { + kfree(bin); v3d_job_put(&render->base); return ret; }

And the second belong to 29cd13cfd7624: commit 29cd13cfd7624726d9e6becbae9aa419ef35af7f Author: Navid Emamdoost navid.emamdoost@gmail.com Date: Mon Oct 21 13:52:49 2019 -0500

drm/v3d: Fix memory leak in v3d_submit_cl_ioctl

In the impelementation of v3d_submit_cl_ioctl() there are two memory leaks. One is when allocation for bin fails, and the other is when bin initialization fails. If kcalloc fails to allocate memory for bin then render->base should be put. Also, if v3d_job_init() fails to initialize bin->base then allocated memory for bin should be released.

Fixes: a783a09ee76d ("drm/v3d: Refactor job management.") Signed-off-by: Navid Emamdoost navid.emamdoost@gmail.com Reviewed-by: Eric Anholt eric@anholt.net Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch Link: https://patchwork.freedesktop.org/patch/msgid/20191021185250.26130-1-navid.e...

diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index 5d80507b539b..19c092d75266 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -557,13 +557,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,

if (args->bcl_start != args->bcl_end) { bin = kcalloc(1, sizeof(*bin), GFP_KERNEL); - if (!bin) + if (!bin) { + v3d_job_put(&render->base); return -ENOMEM; + }

ret = v3d_job_init(v3d, file_priv, &bin->base, v3d_job_free, args->in_sync_bcl); if (ret) { v3d_job_put(&render->base); + kfree(bin); return ret; }

It seems the two patches fix the same memory leak, but I have no idea how thet get together without conflict.

Thanks Yu Kuai