diff options
| author | Kees Cook <keescook@chromium.org> | 2017-02-24 15:00:38 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-24 17:46:56 -0800 |
| commit | 85caa95b9f19bb3a26d7e025d1134760b69e0c40 (patch) | |
| tree | 9db3bbeccc4329287960f42189ba4b1d4ee7a561 /lib | |
| parent | 849de0cd2c873c878fc2605156f10a8ade9bde28 (diff) | |
| download | lwn-85caa95b9f19bb3a26d7e025d1134760b69e0c40.tar.gz lwn-85caa95b9f19bb3a26d7e025d1134760b69e0c40.zip | |
bug: switch data corruption check to __must_check
The CHECK_DATA_CORRUPTION() macro was designed to have callers do
something meaningful/protective on failure. However, using "return
false" in the macro too strictly limits the design patterns of callers.
Instead, let callers handle the logic test directly, but make sure that
the result IS checked by forcing __must_check (which appears to not be
able to be used directly on macro expressions).
Link: http://lkml.kernel.org/r/20170206204547.GA125312@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/list_debug.c | 45 |
1 files changed, 24 insertions, 21 deletions
diff --git a/lib/list_debug.c b/lib/list_debug.c index 7f7bfa55eb6d..a34db8d27667 100644 --- a/lib/list_debug.c +++ b/lib/list_debug.c @@ -20,15 +20,16 @@ bool __list_add_valid(struct list_head *new, struct list_head *prev, struct list_head *next) { - CHECK_DATA_CORRUPTION(next->prev != prev, - "list_add corruption. next->prev should be prev (%p), but was %p. (next=%p).\n", - prev, next->prev, next); - CHECK_DATA_CORRUPTION(prev->next != next, - "list_add corruption. prev->next should be next (%p), but was %p. (prev=%p).\n", - next, prev->next, prev); - CHECK_DATA_CORRUPTION(new == prev || new == next, - "list_add double add: new=%p, prev=%p, next=%p.\n", - new, prev, next); + if (CHECK_DATA_CORRUPTION(next->prev != prev, + "list_add corruption. next->prev should be prev (%p), but was %p. (next=%p).\n", + prev, next->prev, next) || + CHECK_DATA_CORRUPTION(prev->next != next, + "list_add corruption. prev->next should be next (%p), but was %p. (prev=%p).\n", + next, prev->next, prev) || + CHECK_DATA_CORRUPTION(new == prev || new == next, + "list_add double add: new=%p, prev=%p, next=%p.\n", + new, prev, next)) + return false; return true; } @@ -41,18 +42,20 @@ bool __list_del_entry_valid(struct list_head *entry) prev = entry->prev; next = entry->next; - CHECK_DATA_CORRUPTION(next == LIST_POISON1, - "list_del corruption, %p->next is LIST_POISON1 (%p)\n", - entry, LIST_POISON1); - CHECK_DATA_CORRUPTION(prev == LIST_POISON2, - "list_del corruption, %p->prev is LIST_POISON2 (%p)\n", - entry, LIST_POISON2); - CHECK_DATA_CORRUPTION(prev->next != entry, - "list_del corruption. prev->next should be %p, but was %p\n", - entry, prev->next); - CHECK_DATA_CORRUPTION(next->prev != entry, - "list_del corruption. next->prev should be %p, but was %p\n", - entry, next->prev); + if (CHECK_DATA_CORRUPTION(next == LIST_POISON1, + "list_del corruption, %p->next is LIST_POISON1 (%p)\n", + entry, LIST_POISON1) || + CHECK_DATA_CORRUPTION(prev == LIST_POISON2, + "list_del corruption, %p->prev is LIST_POISON2 (%p)\n", + entry, LIST_POISON2) || + CHECK_DATA_CORRUPTION(prev->next != entry, + "list_del corruption. prev->next should be %p, but was %p\n", + entry, prev->next) || + CHECK_DATA_CORRUPTION(next->prev != entry, + "list_del corruption. next->prev should be %p, but was %p\n", + entry, next->prev)) + return false; + return true; } |