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Subject2.1.91: Another 'cli(); copy_to_user();' sequence
From
Date

Since it it quite difficult to force an Ugh (result of re-entering the
kernel while interrupts are disabled, for instance through a page
fault) I have instrumented the copy in/out functions and found another
possible place for an Ugh (Bug) in isdn_ppp.c.

int
isdn_ppp_read(int min, struct file *file, char *buf, int count)
{
...
save_flags(flags);
cli();
...
if ((r = copy_to_user_ugh(buf, b->buf, count))) {
restore_flags(flags);
return r;
...
}

Jean

PS: If there is anyone interested I can send a patch with the
instrumented copy in/out functions.

--
I get up each morning, gather my wits.
Pick up the paper, read the obits.
if I'm not there I know I'm not dead.
So I eat a good breakfast and go back to bed. Peete Seeger

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