iomap: error out on file IO when there is no inline_data buffer

Return IO errors if an ->iomap_begin implementation returns an
IOMAP_INLINE buffer but forgets to set the inline_data pointer.
Filesystems should never do this, but we could help fs developers (me)
fix their bugs by handling this more gracefully than crashing the
kernel.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/175803480324.966383.7414345025943296442.stgit@frogsfrogsfrogs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Darrick J. Wong 2025-09-16 08:00:45 -07:00 committed by Christian Brauner
parent 231af8c14f
commit 6a96fb653b
No known key found for this signature in database
GPG Key ID: 91C61BC06578DCA2
2 changed files with 13 additions and 5 deletions

View File

@ -304,6 +304,9 @@ static int iomap_read_inline_data(const struct iomap_iter *iter,
size_t size = i_size_read(iter->inode) - iomap->offset;
size_t offset = offset_in_folio(folio, iomap->offset);
if (WARN_ON_ONCE(!iomap->inline_data))
return -EIO;
if (folio_test_uptodate(folio))
return 0;
@ -894,7 +897,7 @@ static bool __iomap_write_end(struct inode *inode, loff_t pos, size_t len,
return true;
}
static void iomap_write_end_inline(const struct iomap_iter *iter,
static bool iomap_write_end_inline(const struct iomap_iter *iter,
struct folio *folio, loff_t pos, size_t copied)
{
const struct iomap *iomap = &iter->iomap;
@ -903,12 +906,16 @@ static void iomap_write_end_inline(const struct iomap_iter *iter,
WARN_ON_ONCE(!folio_test_uptodate(folio));
BUG_ON(!iomap_inline_data_valid(iomap));
if (WARN_ON_ONCE(!iomap->inline_data))
return false;
flush_dcache_folio(folio);
addr = kmap_local_folio(folio, pos);
memcpy(iomap_inline_data(iomap, pos), addr, copied);
kunmap_local(addr);
mark_inode_dirty(iter->inode);
return true;
}
/*
@ -921,10 +928,8 @@ static bool iomap_write_end(struct iomap_iter *iter, size_t len, size_t copied,
const struct iomap *srcmap = iomap_iter_srcmap(iter);
loff_t pos = iter->pos;
if (srcmap->type == IOMAP_INLINE) {
iomap_write_end_inline(iter, folio, pos, copied);
return true;
}
if (srcmap->type == IOMAP_INLINE)
return iomap_write_end_inline(iter, folio, pos, copied);
if (srcmap->flags & IOMAP_F_BUFFER_HEAD) {
size_t bh_written;

View File

@ -519,6 +519,9 @@ static int iomap_dio_inline_iter(struct iomap_iter *iomi, struct iomap_dio *dio)
loff_t pos = iomi->pos;
u64 copied;
if (WARN_ON_ONCE(!inline_data))
return -EIO;
if (WARN_ON_ONCE(!iomap_inline_data_valid(iomap)))
return -EIO;