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From:   Haonan Li <lihaonan1105@gmail.com>
To:     Sergey Shtylyov <s.shtylyov@omp.ru>,
        Damien Le Moal <dlemoal@kernel.org>,
        linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     Haonan Li <lihaonan1105@gmail.com>
Subject: [PATCH] pata_lagacy: Handle failed ATA timing computation in opti82c46x_set_piomode
Date:   Tue, 17 Oct 2023 23:32:34 +0000
Message-Id: <20231017233234.2170437-1-lihaonan1105@gmail.com>
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The function opti82c46x_set_piomode utilizes the ata_timing_compute()
to determine the appropriate ATA timings for a given device. However,
in certain conditions where the ata_timing_find_mode() function does
not find a valid mode, ata_timing_compute() returns an error (-EINVAL),
leaving the tp struct uninitialized.

This patch checks the return value of ata_timing_compute().
This avoids any potential use of uninitialized `tp` struct in the
opti82c46x_set_piomode function.

Signed-off-by: Haonan Li <lihaonan1105@gmail.com>
---
 drivers/ata/pata_legacy.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/pata_legacy.c b/drivers/ata/pata_legacy.c
index 448a511cb..d94c365cb 100644
--- a/drivers/ata/pata_legacy.c
+++ b/drivers/ata/pata_legacy.c
@@ -579,12 +579,16 @@ static void opti82c46x_set_piomode(struct ata_port *ap, struct ata_device *adev)
 	clock = 1000000000 / khz[sysclk];
 
 	/* Get the timing data in cycles */
-	ata_timing_compute(adev, adev->pio_mode, &t, clock, 1000);
+	if (ata_timing_compute(adev, adev->pio_mode, &t, clock, 1000)) {
+		return;
+	}
 
 	/* Setup timing is shared */
 	if (pair) {
 		struct ata_timing tp;
-		ata_timing_compute(pair, pair->pio_mode, &tp, clock, 1000);
+		if (ata_timing_compute(pair, pair->pio_mode, &tp, clock, 1000)) {
+			return;
+		}
 
 		ata_timing_merge(&t, &tp, &t, ATA_TIMING_SETUP);
 	}
-- 
2.34.1