From f5a44db5d2d677dfbf12deee461f85e9ec633961 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Fri, 20 Dec 2013 09:29:35 -0500 Subject: ext4: add explicit casts when masking cluster sizes The missing casts can cause the high 64-bits of the physical blocks to be lost. Set up new macros which allows us to make sure the right thing happen, even if at some point we end up supporting larger logical block numbers. Thanks to the Emese Revfy and the PaX security team for reporting this issue. Reported-by: PaX Team Reported-by: Emese Revfy Signed-off-by: "Theodore Ts'o" Cc: stable@vger.kernel.org --- fs/ext4/mballoc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/ext4/mballoc.c') diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 04766d9a29cd..04a5c7504be9 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4126,7 +4126,7 @@ ext4_mb_initialize_context(struct ext4_allocation_context *ac, ext4_get_group_no_and_offset(sb, goal, &group, &block); /* set up allocation goals */ - ac->ac_b_ex.fe_logical = ar->logical & ~(sbi->s_cluster_ratio - 1); + ac->ac_b_ex.fe_logical = EXT4_LBLK_CMASK(sbi, ar->logical); ac->ac_status = AC_STATUS_CONTINUE; ac->ac_sb = sb; ac->ac_inode = ar->inode; @@ -4668,7 +4668,7 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode, * blocks at the beginning or the end unless we are explicitly * requested to avoid doing so. */ - overflow = block & (sbi->s_cluster_ratio - 1); + overflow = EXT4_PBLK_COFF(sbi, block); if (overflow) { if (flags & EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER) { overflow = sbi->s_cluster_ratio - overflow; @@ -4682,7 +4682,7 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode, count += overflow; } } - overflow = count & (sbi->s_cluster_ratio - 1); + overflow = EXT4_LBLK_COFF(sbi, count); if (overflow) { if (flags & EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER) { if (count > overflow) -- cgit v1.2.3