genirq: Fix chained interrupt data ordering
authorThomas Gleixner <tglx@linutronix.de>
Thu, 11 May 2017 11:54:11 +0000 (13:54 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 25 May 2017 13:44:46 +0000 (15:44 +0200)
commit423f1752a0283b3f54f175be893f610f51b3aaf5
tree33d6ad60b7e1ee45149b96d87bbac0a9e8fe7a80
parent3fe116563d5ddc2e3a506eb4b227164e5ccaed23
genirq: Fix chained interrupt data ordering

commit 2c4569ca26986d18243f282dd727da27e9adae4c upstream.

irq_set_chained_handler_and_data() sets up the chained interrupt and then
stores the handler data.

That's racy against an immediate interrupt which gets handled before the
store of the handler data happened. The handler will dereference a NULL
pointer and crash.

Cure it by storing handler data before installing the chained handler.

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/irq/chip.c