From: Simon Glass <simon.glass@canonical.com> Some blkmap slices (like blkmap_crypt) don't support writes and have their write function set to NULL. The blkmap_blk_write_slice() function calls the write function without checking if it's NULL, causing a crash when attempting to write to such slices. Add a NULL check before calling the write function. When the slice doesn't support writes, return 0 to indicate no blocks were written. Co-developed-by: Claude <noreply@anthropic.com> Signed-off-by: Simon Glass <simon.glass@canonical.com> --- (no changes since v1) drivers/block/blkmap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/block/blkmap.c b/drivers/block/blkmap.c index 14aa1e4d088..bd55bdf24b7 100644 --- a/drivers/block/blkmap.c +++ b/drivers/block/blkmap.c @@ -281,6 +281,9 @@ static ulong blkmap_blk_write_slice(struct blkmap *bm, struct blkmap_slice *bms, { lbaint_t nr, cnt; + if (!bms->write) + return 0; + nr = blknr - bms->blknr; cnt = (blkcnt < bms->blkcnt) ? blkcnt : bms->blkcnt; return bms->write(bm, bms, nr, cnt, buffer); -- 2.43.0