Re: [syzbot] Re: [syzbot] [erofs?] KMSAN: uninit-value in z_erofs_lz4_decompress (2)

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Subject: Re: [syzbot] [erofs?] KMSAN: uninit-value in z_erofs_lz4_decompress (2)
Author: eadavis@qq.com

please test uninit-value in z_erofs_lz4_decompress (2)

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git fbafc3e621c3

diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index 021be5feb1bc..f4cc77e3255f 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -250,7 +250,8 @@ static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx,
 		print_hex_dump(KERN_DEBUG, "[ in]: ", DUMP_PREFIX_OFFSET,
 			       16, 1, src + inputmargin, rq->inputsize, true);
 		print_hex_dump(KERN_DEBUG, "[out]: ", DUMP_PREFIX_OFFSET,
-			       16, 1, out, rq->outputsize, true);
+			       16, 1, out, ret < 0 ? (ret + rq->inputsize) : 
+			       rq->outputsize, true);
 
 		if (ret >= 0)
 			memset(out + ret, 0, rq->outputsize - ret);