diff options
author | Oleg Nesterov <oleg@redhat.com> | 2010-08-09 20:20:30 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-09 23:45:05 -0400 |
commit | 2ee7c922f20c96dba56fd378a466790d87f42e84 (patch) | |
tree | 9eda39ff1867c4695c1e7349045ccc23176b623b /kernel/exec_domain.c | |
parent | 5bf1d290b57e392eaf4bfb15c67f315fce4140be (diff) |
sys_personality: remove the bogus checks in sys_personality()->__set_personality() path
Cleanup, no functional changes.
- __set_personality() always changes ->exec_domain/personality, the
special case when ->exec_domain remains the same buys nothing but
complicates the code. Unify both cases to simplify the code.
- The -EINVAL check in sys_personality() was never right. If we assume
that set_personality() can fail we should check the value it returns
instead of verifying that task->personality was actually changed.
Remove it. Before the previous patch it was possible to hit this case
due to overflow problems, but this -EINVAL just indicated the kernel
bug.
OTOH, probably it makes sense to change lookup_exec_domain() to return
ERR_PTR() instead of default_exec_domain if the search in exec_domains
list fails, and report this error to the user-space. But this means
another user-space change, and we have in-kernel users which need fixes.
For example, PER_OSF4 falls into PER_MASK for unkown reason and nobody
cares to register this domain.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Wenming Zhang <wezhang@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/exec_domain.c')
-rw-r--r-- | kernel/exec_domain.c | 22 |
1 files changed, 5 insertions, 17 deletions
diff --git a/kernel/exec_domain.c b/kernel/exec_domain.c index dd62f8e714ca..0dbeae374225 100644 --- a/kernel/exec_domain.c +++ b/kernel/exec_domain.c | |||
@@ -134,23 +134,14 @@ unregister: | |||
134 | return 0; | 134 | return 0; |
135 | } | 135 | } |
136 | 136 | ||
137 | int | 137 | int __set_personality(unsigned int personality) |
138 | __set_personality(unsigned int personality) | ||
139 | { | 138 | { |
140 | struct exec_domain *ep, *oep; | 139 | struct exec_domain *oep = current_thread_info()->exec_domain; |
141 | |||
142 | ep = lookup_exec_domain(personality); | ||
143 | if (ep == current_thread_info()->exec_domain) { | ||
144 | current->personality = personality; | ||
145 | module_put(ep->module); | ||
146 | return 0; | ||
147 | } | ||
148 | 140 | ||
141 | current_thread_info()->exec_domain = lookup_exec_domain(personality); | ||
149 | current->personality = personality; | 142 | current->personality = personality; |
150 | oep = current_thread_info()->exec_domain; | ||
151 | current_thread_info()->exec_domain = ep; | ||
152 | |||
153 | module_put(oep->module); | 143 | module_put(oep->module); |
144 | |||
154 | return 0; | 145 | return 0; |
155 | } | 146 | } |
156 | 147 | ||
@@ -192,11 +183,8 @@ SYSCALL_DEFINE1(personality, unsigned int, personality) | |||
192 | { | 183 | { |
193 | unsigned int old = current->personality; | 184 | unsigned int old = current->personality; |
194 | 185 | ||
195 | if (personality != 0xffffffff) { | 186 | if (personality != 0xffffffff) |
196 | set_personality(personality); | 187 | set_personality(personality); |
197 | if (current->personality != personality) | ||
198 | return -EINVAL; | ||
199 | } | ||
200 | 188 | ||
201 | return old; | 189 | return old; |
202 | } | 190 | } |