Arnd Bergmann
287980e49f
remove lots of IS_ERR_VALUE abuses ...
Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.
However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.
Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.
This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.
Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err < 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.
I was using this definition for testing:
#define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \
unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO))
which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.
I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.
[ Updated the 9p parts as per Al Viro - Linus ]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> # For nvmem part
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-27 15:26:11 -07:00
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-05-25 17:05:40 -07:00
mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings
2016-02-22 08:51:37 +01:00
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-05-25 17:05:40 -07:00
gcov: disable for COMPILE_TEST
2016-05-10 17:12:49 +02:00
radix-tree: introduce radix_tree_empty
2016-05-20 17:58:30 -07:00
Merge branches 'for-4.7/core', 'for-4.7/livepatching-doc' and 'for-4.7/livepatching-ppc64' into for-linus
2016-05-17 12:06:35 +02:00
Fix a number of bugs, most notably a potential stale data exposure
2016-05-24 12:55:26 -07:00
PM / Hibernate: Call flush_icache_range() on pages restored in-place
2016-04-28 13:35:48 +01:00
printk/nmi: flush NMI messages on the system panic
2016-05-20 17:58:30 -07:00
debugobjects: insulate non-fixup logic related to static obj from fixup callbacks
2016-05-19 19:12:14 -07:00
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-05-25 17:11:43 -07:00
debugobjects: insulate non-fixup logic related to static obj from fixup callbacks
2016-05-19 19:12:14 -07:00
Three more changes.
2016-05-22 19:40:39 -07:00
certs: add .gitignore to stop git nagging about x509_certificate_list
2015-10-21 15:18:35 +01:00
async: export current_is_async()
2015-11-19 17:51:48 +01:00
Merge branch 'stable-4.7' of git://git.infradead.org/users/pcmoore/audit
2016-05-18 18:46:55 -07:00
security: Make inode argument of inode_getsecid non-const
2015-12-24 11:09:39 -05:00
wrappers for ->i_mutex access
2016-01-22 18:04:28 -05:00
audit: cleanup prune_tree_thread
2016-04-04 09:46:47 -04:00
don't bother with ->d_inode->i_sb - it's always equal to ->d_sb
2016-04-10 17:11:51 -04:00
audit: Fix typo in comment
2016-02-08 11:25:39 -05:00
Merge branch 'stable-4.7' of git://git.infradead.org/users/pcmoore/audit
2016-05-18 18:46:55 -07:00
cgroup: fix compile warning
2016-05-12 11:05:27 -04:00
cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends
2015-12-03 10:24:08 -05:00
cgroup_pids: fix a typo.
2015-12-14 14:54:37 -05:00
context_tracking: Switch to new static_branch API
2015-11-24 09:56:43 +01:00
sched/hotplug: Make activate() the last hotplug step
2016-05-06 14:58:25 +02:00
kernel/cpu_pm: fix cpu_cluster_pm_exit comment
2015-09-03 02:42:20 +02:00
cpuset: use static key better and convert to new API
2016-05-19 19:12:14 -07:00
kmemcg: account certain kmem allocations to memcg
2016-01-14 16:00:49 -08:00
kmemcg: account certain kmem allocations to memcg
2016-01-14 16:00:49 -08:00
wait: allow sys_waitid() to accept __WNOTHREAD/__WCLONE/__WALL
2016-05-23 17:04:14 -07:00
kernel/extable.c: remove duplicated include
2015-09-10 13:29:01 -07:00
mm: oom_reaper: remove some bloat
2016-05-26 15:35:44 -07:00
x86: remove more uaccess_32.h complexity
2016-05-22 17:21:27 -07:00
ptrace: use fsuid, fsgid, effective creds for fs access checks
2016-01-20 17:09:18 -08:00
kernel/hung_task.c: use timeout diff when timeout is updated
2016-03-22 15:36:02 -07:00
treewide: Remove old email address
2015-11-23 09:44:58 +01:00
treewide: Remove old email address
2015-11-23 09:44:58 +01:00
kallsyms: add support for relative offsets in kallsyms address table
2016-03-15 16:55:16 -07:00
ptrace: use fsuid, fsgid, effective creds for fs access checks
2016-01-20 17:09:18 -08:00
kcov: don't profile branches in kcov
2016-04-28 19:34:04 -07:00
s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres()
2016-05-23 17:04:14 -07:00
s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres()
2016-05-23 17:04:14 -07:00
kexec: introduce a protection mechanism for the crashkernel reserved memory
2016-05-23 17:04:14 -07:00
kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE
2016-01-20 17:09:18 -08:00
kmod: don't run async usermode helper as a child of kworker thread
2015-10-23 17:55:10 +09:00
rcu: Remove TINY_RCU bloat from pointless boot parameters
2015-12-07 16:59:37 -08:00
kernel/kthread.c:kthread_create_on_node(): clarify documentation
2015-09-04 16:54:41 -07:00
sched/debug: Make schedstats a runtime tunable that is disabled by default
2016-02-09 11:54:23 +01:00
ELF/MIPS build fix
2016-05-23 17:04:14 -07:00
sys_membarrier(): system-wide memory barrier (generic, x86)
2015-09-11 15:21:34 -07:00
memremap: add arch specific hook for MEMREMAP_WB mappings
2016-04-04 10:26:41 +02:00
module: preserve Elf information for livepatch modules
2016-04-01 15:00:10 +02:00
KEYS: Move the point of trust determination to __key_link()
2016-04-11 22:43:43 +01:00
cgroup: introduce cgroup namespaces
2016-02-16 13:04:58 -05:00
kernel/padata.c: hide unused functions
2016-05-19 19:12:14 -07:00
printk/nmi: flush NMI messages on the system panic
2016-05-20 17:58:30 -07:00
Nothing exciting, minor tweaks and cleanups.
2015-11-09 15:53:39 -08:00
remove lots of IS_ERR_VALUE abuses
2016-05-27 15:26:11 -07:00
profile: hide unused functions when !CONFIG_PROC_FS
2016-03-22 15:36:02 -07:00
ptrace: change __ptrace_unlink() to clear ->ptrace under ->siglock
2016-03-22 15:36:02 -07:00
kexec: split kexec_load syscall from kexec core code
2015-09-10 13:29:01 -07:00
wrappers for ->i_mutex access
2016-01-22 18:04:28 -05:00
/proc/iomem: only expose physical resource addresses to privileged users
2016-04-14 12:56:09 -07:00
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
2016-05-19 10:02:26 -07:00
kernel/signal.c: convert printk(KERN_<LEVEL> ...) to pr_<level>(...)
2016-05-23 17:04:14 -07:00
Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-03-15 13:50:29 -07:00
cpu/hotplug: Unpark smpboot threads from the state machine
2016-03-01 20:36:56 +01:00
cpu/hotplug: Create hotplug threads
2016-03-01 20:36:56 +01:00
arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
2016-03-25 16:37:42 -07:00
kernel/stop_machine.c: remove CONFIG_SMP dependencies
2016-01-16 11:17:24 -08:00
prctl: make PR_SET_THP_DISABLE wait for mmap_sem killable
2016-05-23 17:04:14 -07:00
vfs: add copy_file_range syscall and vfs helper
2015-12-01 14:00:53 -05:00
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-05-25 17:05:40 -07:00
kernel/sysctl_binary.c: use generic UUID library
2016-05-20 17:58:30 -07:00
task_work: remove fifo ordering guarantee
2015-09-05 13:46:58 -07:00
taskstats: use the libnl API to align nlattr on 64-bit
2016-04-23 20:13:25 -04:00
rcutorture: Dump trace buffer upon shutdown
2016-04-21 13:47:04 -07:00
kernel/...: convert pr_warning to pr_warn
2016-03-22 15:36:02 -07:00
time, acct: Drop irq save & restore from __acct_update_integrals()
2016-02-29 09:53:09 +01:00
kernel/*: switch to memdup_user_nul()
2016-01-04 10:27:55 -05:00
watchdog: don't run proc_watchdog_update if new value is same as old
2016-03-17 15:09:34 -07:00
debugobjects: insulate non-fixup logic related to static obj from fixup callbacks
2016-05-19 19:12:14 -07:00
sched/core: Get rid of 'cpu' argument in wq_worker_sleeping()
2016-03-02 10:28:47 -05:00
287980e49f