[tip: irq/urgent] irqchip/gic-v3-its: Prevent double free on error

From: tip-bot2 for Guanrui Huang
Date: Thu Apr 25 2024 - 08:47:03 EST


The following commit has been merged into the irq/urgent branch of tip:

Commit-ID: c26591afd33adce296c022e3480dea4282b7ef91
Gitweb: https://git.kernel.org/tip/c26591afd33adce296c022e3480dea4282b7ef91
Author: Guanrui Huang <guanrui.huang@xxxxxxxxxxxxxxxxx>
AuthorDate: Thu, 18 Apr 2024 14:10:52 +08:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Thu, 25 Apr 2024 14:30:46 +02:00

irqchip/gic-v3-its: Prevent double free on error

The error handling path in its_vpe_irq_domain_alloc() causes a double free
when its_vpe_init() fails after successfully allocating at least one
interrupt. This happens because its_vpe_irq_domain_free() frees the
interrupts along with the area bitmap and the vprop_page and
its_vpe_irq_domain_alloc() subsequently frees the area bitmap and the
vprop_page again.

Fix this by unconditionally invoking its_vpe_irq_domain_free() which
handles all cases correctly and by removing the bitmap/vprop_page freeing
from its_vpe_irq_domain_alloc().

[ tglx: Massaged change log ]

Fixes: 7d75bbb4bc1a ("irqchip/gic-v3-its: Add VPE irq domain allocation/teardown")
Signed-off-by: Guanrui Huang <guanrui.huang@xxxxxxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Marc Zyngier <maz@xxxxxxxxxx>
Reviewed-by: Zenghui Yu <yuzenghui@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20240418061053.96803-2-guanrui.huang@xxxxxxxxxxxxxxxxx
---
drivers/irqchip/irq-gic-v3-its.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 2a537cb..5f7d3db 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -4567,13 +4567,8 @@ static int its_vpe_irq_domain_alloc(struct irq_domain *domain, unsigned int virq
irqd_set_resend_when_in_progress(irq_get_irq_data(virq + i));
}

- if (err) {
- if (i > 0)
- its_vpe_irq_domain_free(domain, virq, i);
-
- its_lpi_free(bitmap, base, nr_ids);
- its_free_prop_table(vprop_page);
- }
+ if (err)
+ its_vpe_irq_domain_free(domain, virq, i);

return err;
}