Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
pps: locking scheme fix up for PPS_GETPARAMS
Userland programs may read/write PPS parameters at same time and these
operations may corrupt PPS data.
Signed-off-by: Rodolfo Giometti <giometti@linux.it>
Tested-by: Reg Clemens <clemens@dwf.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
authored by
Rodolfo Giometti
and committed by
Linus Torvalds
cbf83cc5
69fd8d24
+8
-3
+8
-3
drivers/pps/pps.c
+8
-3
drivers/pps/pps.c
···
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case PPS_GETPARAMS:
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pr_debug("PPS_GETPARAMS: source %d\n", pps->id);
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-
/* Return current parameters */
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-
err = copy_to_user(uarg, &pps->params,
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-
sizeof(struct pps_kparams));
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+
spin_lock_irq(&pps->lock);
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+
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/* Get the current parameters */
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params = pps->params;
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+
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spin_unlock_irq(&pps->lock);
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err = copy_to_user(uarg, ¶ms, sizeof(struct pps_kparams));
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if (err)
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return -EFAULT;
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