6.12-stable review patch. If anyone has any objections, please let me know.
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From: Sanjay Yadav sanjay.kumar.yadav@intel.com
commit dcb171931954c51a1a7250d558f02b8f36570783 upstream.
In xe_oa_add_config_ioctl(), we accessed oa_config->id after dropping metrics_lock. Since this lock protects the lifetime of oa_config, an attacker could guess the id and call xe_oa_remove_config_ioctl() with perfect timing, freeing oa_config before we dereference it, leading to a potential use-after-free.
Fix this by caching the id in a local variable while holding the lock.
v2: (Matt A) - Dropped mutex_unlock(&oa->metrics_lock) ordering change from xe_oa_remove_config_ioctl()
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6614 Fixes: cdf02fe1a94a7 ("drm/xe/oa/uapi: Add/remove OA config perf ops") Cc: stable@vger.kernel.org # v6.11+ Suggested-by: Matthew Auld matthew.auld@intel.com Signed-off-by: Sanjay Yadav sanjay.kumar.yadav@intel.com Reviewed-by: Matthew Auld matthew.auld@intel.com Signed-off-by: Matthew Auld matthew.auld@intel.com Link: https://patch.msgid.link/20251118114859.3379952-2-sanjay.kumar.yadav@intel.c... (cherry picked from commit 28aeaed130e8e587fd1b73b6d66ca41ccc5a1a31) Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/xe/xe_oa.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/xe/xe_oa.c +++ b/drivers/gpu/drm/xe/xe_oa.c @@ -2378,11 +2378,13 @@ int xe_oa_add_config_ioctl(struct drm_de goto sysfs_err; }
- mutex_unlock(&oa->metrics_lock); + id = oa_config->id; + + drm_dbg(&oa->xe->drm, "Added config %s id=%i\n", oa_config->uuid, id);
- drm_dbg(&oa->xe->drm, "Added config %s id=%i\n", oa_config->uuid, oa_config->id); + mutex_unlock(&oa->metrics_lock);
- return oa_config->id; + return id;
sysfs_err: mutex_unlock(&oa->metrics_lock);