[Intel-gfx] [PATCH] drm/i915: Fix bug in user proto-context creation that leaked contexts

Matthew Brost
2021-10-01T16:05:24Z

Set number of engines before attempting to create contexts so the
function free_engines can clean up properly. Also check return of
alloc_engines for NULL.

v2:
(Tvrtko)
- Send as stand alone patch
(John Harrison)
- Check for alloc_engines returning NULL
v3:
(Checkpatch / Tvrtko)
- Remove braces around single line if statement

Cc: Jason Ekstrand <jason@jlekstrand.net>
Fixes: d4433c7600f7 ("drm/i915/gem: Use the proto-context to handle create parameters (v5)")
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Cc: <stable@vger.kernel.org>
---
drivers/gpu/drm/i915/gem/i915_gem_context.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 8208fd5b72c3..8c7ea6e56262 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -898,6 +898,10 @@ static struct i915_gem_engines *user_engines(struct i915_gem_context *ctx,
unsigned int n;

e = alloc_engines(num_engines);
+ if (!e)
+ return ERR_PTR(-ENOMEM);
+ e->num_engines = num_engines;
+
for (n = 0; n < num_engines; n++) {
struct intel_context *ce;
int ret;
@@ -931,7 +935,6 @@ static struct i915_gem_engines *user_engines(struct i915_gem_context *ctx,
goto free_engines;
}
}
- e->num_engines = num_engines;

return e;

--
2.32.0