From: Arnd Bergmann Date: Wed, 3 Apr 2013 19:53:57 +0000 (+0200) Subject: block: avoid using uninitialized value in from queue_var_store X-Git-Tag: v3.2.44~10 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=4316936730689af432346fa1d71c3f69f22ec3ac block: avoid using uninitialized value in from queue_var_store commit c678ef5286ddb5cf70384ad5af286b0afc9b73e1 upstream. As found by gcc-4.8, the QUEUE_SYSFS_BIT_FNS macro creates functions that use a value generated by queue_var_store independent of whether that value was set or not. block/blk-sysfs.c: In function 'queue_store_nonrot': block/blk-sysfs.c:244:385: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized] Unlike most other such warnings, this one is not a false positive, writing any non-number string into the sysfs files indeed has an undefined result, rather than returning an error. Signed-off-by: Arnd Bergmann Signed-off-by: Jens Axboe Signed-off-by: Ben Hutchings --- diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index f0b2ca8f66d0..1789e7abd868 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -200,6 +200,8 @@ queue_store_##name(struct request_queue *q, const char *page, size_t count) \ unsigned long val; \ ssize_t ret; \ ret = queue_var_store(&val, page, count); \ + if (ret < 0) \ + return ret; \ if (neg) \ val = !val; \ \