ia64: Pin controlling tty for unaligned fault message
PATCH 1/1 ia64: Pin controlling tty for unaligned fault message
Prevent destruction of the controlling tty before tty_write_message() can determine if the tty is safe to use.
Signed-off-by Peter Hurley <[email protected]>
--- arch/ia64/kernel/unaligned.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
arch/ia64/kernel/unaligned.c +5 -2
@@ -1336,8 +1336,11 @@ ia64_handle_unaligned (unsigned long ifa, struct pt_regs *regs)* Don't call tty_write_message() if we're in the kernel; we might * be holding locks... */ -if (user_mode (regs)) -tty_write_message (current->signal->tty, buf); +if (user_mode (regs)) { +struct tty_struct *tty =get_current_tty (); +tty_write_message (tty, buf); +tty_kref_put (tty); + } buf[len-1 ] ='\0' ;/* drop '\r' */ /* watch for command names containing %s */ printk (KERN_WARNING "%s" , buf);
Signature · 1 line
2.1.1
Quoted 2 lines · Peter Hurley
Prevent destruction of the controlling tty before
tty_write_message()can determine if the tty is safe to use.
This does not make tty_write_message() bulletproof from concurrent teardown, but that's on my todo list.
Quoted 24 lines
Signed-off-by Peter Hurley <[email protected]>--- arch/ia64/kernel/unaligned.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)arch/ia64/kernel/unaligned.c +5
-2@@ -1336,8 +1336,11 @@ ia64_handle_unaligned (unsigned long ifa, struct pt_regs *regs)* Don't call tty_write_message() if we're in the kernel; we might * be holding locks... */ -if (user_mode (regs)) -tty_write_message (current->signal->tty, buf); +if (user_mode (regs)) { +struct tty_struct *tty =get_current_tty (); +tty_write_message (tty, buf); +tty_kref_put (tty); + } buf[len-1 ] ='\0' ;/* drop '\r' */ /* watch for command names containing %s */ printk (KERN_WARNING "%s" , buf);