3.5.7.2 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Roland Dreier <[email protected]> commit 3e03989b5868acf69a391a424dc71fcd6cc48167 upstream. The expression (max_sectors * block_size) might overflow a u32 (indeed, since iblock sets max_hw_sectors to UINT_MAX, it is guaranteed to overflow and end up with a much-too-small result in many common cases). Fix this by doing an equivalent calculation that doesn't require multiplication. While we're touching this code, avoid splitting a printk format across two lines and use pr_info(...) instead of printk(KERN_INFO ...). Signed-off-by: Roland Dreier <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> [ herton: unfuzz patch ] Signed-off-by: Herton Ronaldo Krzesinski <[email protected]> --- drivers/target/target_core_device.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index 5ad9728..8542099 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -824,20 +824,20 @@ int se_dev_check_shutdown(struct se_device *dev) u32 se_dev_align_max_sectors(u32 max_sectors, u32 block_size) { - u32 tmp, aligned_max_sectors; + u32 aligned_max_sectors; + u32 alignment; /* * Limit max_sectors to a PAGE_SIZE aligned value for modern * transport_allocate_data_tasks() operation. */ - tmp = rounddown((max_sectors * block_size), PAGE_SIZE); - aligned_max_sectors = (tmp / block_size); - if (max_sectors != aligned_max_sectors) { - printk(KERN_INFO "Rounding down aligned max_sectors from %u" - " to %u\n", max_sectors, aligned_max_sectors); - return aligned_max_sectors; - } + alignment = max(1ul, PAGE_SIZE / block_size); + aligned_max_sectors = rounddown(max_sectors, alignment); + + if (max_sectors != aligned_max_sectors) + pr_info("Rounding down aligned max_sectors from %u to %u\n", + max_sectors, aligned_max_sectors); - return max_sectors; + return aligned_max_sectors; } void se_dev_set_default_attribs( -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
