To te able to unregister stuff from isrs, the corresponding table was
copied.  Nobody seems to unregister stuff that way, so it does not help.
But there are stack-allocated objects passed to these isrs giving chances
of UAF of these objects if irqs are unregistered while they are handled,
so better do not copy that table.

Suggested-by: [email protected]
Signed-off-by: Andreas Kemnade <[email protected]>
---
Fix for drm variant fo driver:
https://lore.kernel.org/lkml/[email protected]/
---
 drivers/video/fbdev/omap2/omapfb/dss/dsi.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/video/fbdev/omap2/omapfb/dss/dsi.c 
b/drivers/video/fbdev/omap2/omapfb/dss/dsi.c
index 330d9fb7d2b0..d98db01fdd39 100644
--- a/drivers/video/fbdev/omap2/omapfb/dss/dsi.c
+++ b/drivers/video/fbdev/omap2/omapfb/dss/dsi.c
@@ -326,8 +326,6 @@ struct dsi_data {
 
        spinlock_t irq_lock;
        struct dsi_isr_tables isr_tables;
-       /* space for a copy used by the interrupt handler */
-       struct dsi_isr_tables isr_tables_copy;
 
        int update_channel;
 #ifdef DSI_PERF_MEASURE
@@ -838,15 +836,10 @@ static irqreturn_t omap_dsi_irq_handler(int irq, void 
*arg)
                timer_delete(&dsi->te_timer);
 #endif
 
-       /* make a copy and unlock, so that isrs can unregister
-        * themselves */
-       memcpy(&dsi->isr_tables_copy, &dsi->isr_tables,
-               sizeof(dsi->isr_tables));
 
+       dsi_handle_isrs(&dsi->isr_tables, irqstatus, vcstatus, ciostatus);
        spin_unlock(&dsi->irq_lock);
 
-       dsi_handle_isrs(&dsi->isr_tables_copy, irqstatus, vcstatus, ciostatus);
-
        dsi_handle_irq_errors(dsidev, irqstatus, vcstatus, ciostatus);
 
        dsi_collect_irq_stats(dsidev, irqstatus, vcstatus, ciostatus);

---
base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482
change-id: 20260702-fbomap-uaf-fix-167ed8a8bf38

Best regards,
--  
Andreas Kemnade <[email protected]>

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