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| author | Kiselev, Oleg <okiselev@amazon.com> | 2022-07-20 04:27:48 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-25 11:38:18 +0200 |
| commit | 80288883294c5b4ed18bae0d8bd9c4a12f297074 (patch) | |
| tree | 47a4f5fa72d1448bd78fd1f9ba9aba2d34da1f60 | |
| parent | 285447b81925ff785533c677d552c97818081181 (diff) | |
| download | linux-80288883294c5b4ed18bae0d8bd9c4a12f297074.tar.gz linux-80288883294c5b4ed18bae0d8bd9c4a12f297074.tar.bz2 linux-80288883294c5b4ed18bae0d8bd9c4a12f297074.zip | |
ext4: avoid resizing to a partial cluster size
[ Upstream commit 69cb8e9d8cd97cdf5e293b26d70a9dee3e35e6bd ]
This patch avoids an attempt to resize the filesystem to an
unaligned cluster boundary. An online resize to a size that is not
integral to cluster size results in the last iteration attempting to
grow the fs by a negative amount, which trips a BUG_ON and leaves the fs
with a corrupted in-memory superblock.
Signed-off-by: Oleg Kiselev <okiselev@amazon.com>
Link: https://lore.kernel.org/r/0E92A0AB-4F16-4F1A-94B7-702CC6504FDE@amazon.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | fs/ext4/resize.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 5cfea77f3322..f6409ddfd117 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1957,6 +1957,16 @@ int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count) } brelse(bh); + /* + * For bigalloc, trim the requested size to the nearest cluster + * boundary to avoid creating an unusable filesystem. We do this + * silently, instead of returning an error, to avoid breaking + * callers that blindly resize the filesystem to the full size of + * the underlying block device. + */ + if (ext4_has_feature_bigalloc(sb)) + n_blocks_count &= ~((1 << EXT4_CLUSTER_BITS(sb)) - 1); + retry: o_blocks_count = ext4_blocks_count(es); |