linux/arch/parisc/kernel
Eric W. Biederman b5daf2b9d1 signal/parisc: Document a conflict with SI_USER with SIGFPE
Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME siginfo_layout will now return SIL_FAULT and the
appropriate fields will reliably be copied.

This bug is 13 years old and parsic machines are no longer being built
so I don't know if it possible or worth fixing it.  But it is at least
worth documenting this so other architectures don't make the same
mistake.

Possible ABI fixes includee:
  - Send the signal without siginfo
  - Don't generate a signal
  - Possibly assign and use an appropriate si_code
  - Don't handle cases which can't happen

Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Ref: 313c01d3e3fd ("[PATCH] PA-RISC update for 2.6.0")
Histroy Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-12 14:21:03 -06:00
..
.gitignore
asm-offsets.c parisc: Drop per_cpu uaccess related exception_data struct 2017-05-10 17:46:13 +02:00
audit.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
binfmt_elf32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cache.c parisc: Handle vma's whose context is not current in flush_cache_range 2017-07-31 08:22:33 +02:00
compat_audit.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
drivers.c parisc: parisc_bus_type: use dev_groups and not dev_attrs for bus_type 2017-06-09 11:00:45 +02:00
entry.S Revert "parisc: Re-enable interrupts early" 2017-12-17 21:06:25 +01:00
firmware.c parisc: Add wrapper for pdc_instr() firmware function 2017-09-22 19:46:44 +02:00
ftrace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hardware.c parisc: add serial ports of C8000/1GHz machine to hardware database 2014-07-13 15:51:58 +02:00
head.S parisc: Fix ftrace function tracer 2016-04-14 17:47:19 +02:00
hpmc.S parisc: Align os_hpmc_size on word boundary 2017-12-17 21:06:25 +01:00
inventory.c parisc: Add Page Deallocation Table (PDT) support 2017-05-12 09:14:15 +02:00
irq.c parisc: Increase thread and stack size to 32kb 2017-07-31 08:41:26 +02:00
Makefile parisc: Add CPU topology support 2017-11-17 15:27:22 +01:00
module.c mm, vmalloc: use __GFP_HIGHMEM implicitly 2017-05-08 17:15:13 -07:00
pa7300lc.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pacache.S parisc: Remove unnecessary TLB purges from flush_dcache_page_asm and flush_icache_page_asm 2016-12-07 09:01:21 +01:00
parisc_ksyms.c parisc: Export __cmpxchg_u64 unconditionally 2017-10-19 08:48:45 +02:00
pci-dma.c A couple of dma-mapping updates: 2017-11-14 16:54:12 -08:00
pci.c parisc: Use generic pci_mmap_resource_range() 2017-04-20 08:47:47 -05:00
pdc_chassis.c parisc: single_open() leaks 2013-05-05 00:10:41 -04:00
pdc_cons.c treewide: Switch DEFINE_TIMER callbacks to struct timer_list * 2017-11-21 15:57:05 -08:00
pdt.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
perf_asm.S
perf_images.h
perf.c parisc: Static initialization of spinlocks in perf and unwind code 2017-08-22 16:34:33 +02:00
process.c parisc, watchdog/core: Use lockup_detector_stop() 2017-09-14 11:41:03 +02:00
processor.c parisc: Add CPU topology support 2017-11-17 15:27:22 +01:00
ptrace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
real2.S parisc: Make existing core files reuseable for bootloader 2017-08-22 16:34:35 +02:00
setup.c parisc: Add CPU topology support 2017-11-17 15:27:22 +01:00
signal32.c parisc: switch to {get,put}_compat_sigset() 2017-09-19 17:56:02 -04:00
signal32.h parisc: switch to {get,put}_compat_sigset() 2017-09-19 17:56:02 -04:00
signal.c Merge branch 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-11-17 11:54:55 -08:00
smp.c parisc: Move init_per_cpu() into init section 2017-09-22 19:47:08 +02:00
stacktrace.c
sys_parisc32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sys_parisc.c mm: larger stack guard gap, between vmas 2017-06-19 21:50:20 +08:00
syscall_table.S parisc: use compat_sys_keyctl() 2017-07-02 22:10:47 +02:00
syscall.S parisc: Fix validity check of pointer size argument in new CAS implementation 2017-11-17 15:27:13 +01:00
time.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
topology.c parisc: Add CPU topology support 2017-11-17 15:27:22 +01:00
traps.c signal/parisc: Document a conflict with SI_USER with SIGFPE 2018-01-12 14:21:03 -06:00
unaligned.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h> 2017-03-02 08:42:34 +01:00
unwind.c parisc: remove duplicate includes 2017-12-17 21:06:25 +01:00
vmlinux.lds.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00