Validate the new compression algorithm before copying it into the zram 'compressor' field, keeping the old one if it's invalid.
The error path code is also slightly refactored. Signed-off-by: Luis Henriques <luis.henriq...@canonical.com> --- drivers/block/zram/zram_drv.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 9c01f5bfa33f..33551ec9e7f5 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -367,10 +367,15 @@ static ssize_t comp_algorithm_store(struct device *dev, down_write(&zram->init_lock); if (init_done(zram)) { - up_write(&zram->init_lock); pr_info("Can't change algorithm for initialized device\n"); - return -EBUSY; + len = -EBUSY; + goto out; + } + if (!zcomp_available_algorithm(buf)) { + len = -EINVAL; + goto out; } + strlcpy(zram->compressor, buf, sizeof(zram->compressor)); /* ignore trailing newline */ @@ -378,9 +383,7 @@ static ssize_t comp_algorithm_store(struct device *dev, if (sz > 0 && zram->compressor[sz - 1] == '\n') zram->compressor[sz - 1] = 0x00; - if (!zcomp_available_algorithm(zram->compressor)) - len = -EINVAL; - +out: up_write(&zram->init_lock); return len; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/