fixup! u-boot: v2026.01: fix BTRFS zstd decompression failure (error 70)

add SIZE_MAX guard for 32-bit platforms

Author: iav

patch/u-boot/v2026.01/board_helios64/general-fix-btrfs-zstd-decompression.patch

@@ -36,13 +36,13 @@ also call their library functions directly without generic wrappers.
 
 Signed-off-by: Igor Velkov <iav-armbian@draconpern.com>
 ---
- fs/btrfs/compression.c | 63 ++++++++++++++++++++++++++++++++++++++++----
- 1 file changed, 59 insertions(+), 4 deletions(-)
+ fs/btrfs/compression.c | 65 ++++++++++++++++++++++++++++++++++++++++++----
+ 1 file changed, 61 insertions(+), 4 deletions(-)
 
 diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
 --- a/fs/btrfs/compression.c
 +++ b/fs/btrfs/compression.c
-@@ -137,12 +137,67 @@
+@@ -137,12 +137,69 @@
 
  static u32 decompress_zstd(const u8 *cbuf, u32 clen, u8 *dbuf, u32 dlen)
  {
@@ -76,6 +76,8 @@ diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
 +	fcs = ZSTD_getFrameContentSize(cbuf, clen);
 +	if (fcs != ZSTD_CONTENTSIZE_ERROR &&
 +	    fcs != ZSTD_CONTENTSIZE_UNKNOWN && fcs > dlen) {
++		if (fcs > SIZE_MAX)
++			return -1;
 +		tmp = malloc(fcs);
 +		if (!tmp)
 +			return -1;