From: Al Viro Date: Wed, 9 Sep 2015 09:16:39 +0000 (+0100) Subject: fix ufs write vs readpage race when writing into a hole X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=bd2843fe1f29f6145c623ae9390f144cefaa611d;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git fix ufs write vs readpage race when writing into a hole Followup to the UFS series - with the way we clear the new blocks (via buffer cache, possibly on more than a page worth of file) we really should not insert a reference to new block into inode block tree until after we'd cleared it. Signed-off-by: Al Viro Signed-off-by: Linus Torvalds --- diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c index fb8b54eb77c5..dc5fae601c24 100644 --- a/fs/ufs/balloc.c +++ b/fs/ufs/balloc.c @@ -417,14 +417,14 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment, if (oldcount == 0) { result = ufs_alloc_fragments (inode, cgno, goal, count, err); if (result) { + ufs_clear_frags(inode, result + oldcount, + newcount - oldcount, locked_page != NULL); write_seqlock(&UFS_I(inode)->meta_lock); ufs_cpu_to_data_ptr(sb, p, result); write_sequnlock(&UFS_I(inode)->meta_lock); *err = 0; UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag, fragment + count); - ufs_clear_frags(inode, result + oldcount, - newcount - oldcount, locked_page != NULL); } mutex_unlock(&UFS_SB(sb)->s_lock); UFSD("EXIT, result %llu\n", (unsigned long long)result);