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

From: syzbot
Date: Wed Dec 27 2023 - 20:11:47 EST


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Subject: [erofs?] KMSAN: uninit-value in z_erofs_lz4_decompress (2)
Author: lizhi.xu@xxxxxxxxxxxxx

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

diff --git a/lib/hexdump.c b/lib/hexdump.c
index 06833d404398..68b30bf6c6a3 100644
--- a/lib/hexdump.c
+++ b/lib/hexdump.c
@@ -263,12 +263,14 @@ void print_hex_dump(const char *level, const char *prefix_str, int prefix_type,
const void *buf, size_t len, bool ascii)
{
const u8 *ptr = buf;
- int i, linelen, remaining = len;
+ int i, linelen, remaining;
unsigned char linebuf[32 * 3 + 2 + 32 + 1];

if (rowsize != 16 && rowsize != 32)
rowsize = 16;

+ len = len > sizeof(linebuf) ? sizeof(linebuf) : len;
+ remaining = len;
for (i = 0; i < len; i += rowsize) {
linelen = min(remaining, rowsize);
remaining -= rowsize;