Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:

 - Convert content from the ext4 wiki to Documentation rst files so it
   is more likely to be updated as we add new features to ext4.

 - Add 64-bit timestamp support to ext4's superblock fields.

 - ... and the usual bug fixes and cleanups, including a Spectre gadget
   fixup and some hardening against maliciously corrupted file systems.

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (34 commits)
  ext4: remove unneeded variable "err" in ext4_mb_release_inode_pa()
  ext4: improve code readability in ext4_iget()
  ext4: fix spectre gadget in ext4_mb_regular_allocator()
  ext4: check for NUL characters in extended attribute's name
  ext4: use ext4_warning() for sb_getblk failure
  ext4: fix race when setting the bitmap corrupted flag
  ext4: reset error code in ext4_find_entry in fallback
  ext4: handle layout changes to pinned DAX mappings
  dax: dax_layout_busy_page() warn on !exceptional
  docs: fix up the obviously obsolete bits in the new ext4 documentation
  docs: add new ext4 superblock time extension fields
  docs: create filesystem internal section
  ext4: use swap macro in mext_page_double_lock
  ext4: check allocation failure when duplicating "data" in ext4_remount()
  ext4: fix warning message in ext4_enable_quotas()
  ext4: super: extend timestamps to 40 bits
  jbd2: replace current_kernel_time64 with ktime equivalent
  ext4: use timespec64 for all inode times
  ext4: use ktime_get_real_seconds for i_dtime
  ext4: use 64-bit timestamps for mmp_time
  ...

1 files changed, 4 insertions, 3 deletions

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index f7ab34088162..e29fce2fbf25 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -14,6 +14,7 @@
 #include <linux/log2.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/nospec.h>
 #include <linux/backing-dev.h>
 #include <trace/events/ext4.h>
 
@@ -2140,7 +2141,8 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
 		 * This should tell if fe_len is exactly power of 2
 		 */
 		if ((ac->ac_g_ex.fe_len & (~(1 << (i - 1)))) == 0)
-			ac->ac_2order = i - 1;
+			ac->ac_2order = array_index_nospec(i - 1,
+							   sb->s_blocksize_bits + 2);
 	}
 
 	/* if stream allocation is enabled, use global goal */
@@ -3799,7 +3801,6 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
 	ext4_group_t group;
 	ext4_grpblk_t bit;
 	unsigned long long grp_blk_start;
-	int err = 0;
 	int free = 0;
 
 	BUG_ON(pa->pa_deleted == 0);
@@ -3840,7 +3841,7 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
 	}
 	atomic_add(free, &sbi->s_mb_discarded);
 
-	return err;
+	return 0;
 }
 
 static noinline_for_stack int