Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
Input: libps2 - fix aborting PS/2 commands
When aborting PS/2 command the kernel should [re]set all flags before
waking up waiters, otherwise waiting thread may read obsolete values
of flags.
Reported-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Raul E Rangel <rrangel@chromium.org>
Link: https://lore.kernel.org/r/20230511185252.386941-6-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
+11
-4
+11
-4
drivers/input/serio/libps2.c
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-4
drivers/input/serio/libps2.c
···
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}
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EXPORT_SYMBOL(ps2_handle_response);
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+
/*
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* Clears state of PS/2 device after communication error by resetting majority
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* of flags and waking up waiters, if any.
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*/
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void ps2_cmd_aborted(struct ps2dev *ps2dev)
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{
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-
if (ps2dev->flags & PS2_FLAG_ACK)
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unsigned long old_flags = ps2dev->flags;
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/* reset all flags except last nak */
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ps2dev->flags &= PS2_FLAG_NAK;
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if (old_flags & PS2_FLAG_ACK)
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ps2dev->nak = 1;
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if (ps2dev->flags & (PS2_FLAG_ACK | PS2_FLAG_CMD))
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if (old_flags & (PS2_FLAG_ACK | PS2_FLAG_CMD))
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wake_up(&ps2dev->wait);
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/* reset all flags except last nack */
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ps2dev->flags &= PS2_FLAG_NAK;
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}
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EXPORT_SYMBOL(ps2_cmd_aborted);