From 404508001e9f2bbf09fc4c4027cf16b8720124db Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= Date: Sat, 12 May 2018 23:34:43 +0200 Subject: kernel: use accepted version of bcm47xxpart fix commit MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Rafał Miłecki --- ...xpart-improve-handling-TRX-partition-size.patch | 65 ---------------------- 1 file changed, 65 deletions(-) delete mode 100644 target/linux/generic/pending-4.9/142-mtd-bcm47xxpart-improve-handling-TRX-partition-size.patch (limited to 'target/linux/generic/pending-4.9') diff --git a/target/linux/generic/pending-4.9/142-mtd-bcm47xxpart-improve-handling-TRX-partition-size.patch b/target/linux/generic/pending-4.9/142-mtd-bcm47xxpart-improve-handling-TRX-partition-size.patch deleted file mode 100644 index 60c8ecbdc5..0000000000 --- a/target/linux/generic/pending-4.9/142-mtd-bcm47xxpart-improve-handling-TRX-partition-size.patch +++ /dev/null @@ -1,65 +0,0 @@ -From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= -Subject: [PATCH] mtd: bcm47xxpart: improve handling TRX partition size -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -When bcm47xxpart finds a TRX partition (container) it's supposed to jump -to the end of it and keep looking for more partitions. TRX and its -subpartitions are handled be a separated parser. - -The problem with old code was relying on the length specified in a TRX -header. That isn't reliable as TRX is commonly modified to have checksum -cover only non-changing subpartitions. Otherwise modifying e.g. a rootfs -would result in CRC32 mismatch and bootloader refusing to boot a -firmware. - -Fix it by trying better to figure out a real TRX size. We can securely -assume that TRX has to cover all subpartitions and the last one is at -least of a block size in size. Then compare it with a length field. - -This makes code more optimal & reliable thanks to skipping data that -shouldn't be parsed. - -Signed-off-by: Rafał Miłecki ---- - ---- a/drivers/mtd/bcm47xxpart.c -+++ b/drivers/mtd/bcm47xxpart.c -@@ -186,6 +186,8 @@ static int bcm47xxpart_parse(struct mtd_ - /* TRX */ - if (buf[0x000 / 4] == TRX_MAGIC) { - struct trx_header *trx; -+ uint32_t last_subpart; -+ uint32_t trx_size; - - if (trx_num >= ARRAY_SIZE(trx_parts)) - pr_warn("No enough space to store another TRX found at 0x%X\n", -@@ -195,11 +197,23 @@ static int bcm47xxpart_parse(struct mtd_ - bcm47xxpart_add_part(&parts[curr_part++], "firmware", - offset, 0); - -- /* Jump to the end of TRX */ -+ /* -+ * Try to find TRX size. The "length" field isn't fully -+ * reliable as it could be decreased to make CRC32 cover -+ * only part of TRX data. It's commonly used as checksum -+ * can't cover e.g. ever-changing rootfs partition. -+ * Use offsets as helpers for assuming min TRX size. -+ */ - trx = (struct trx_header *)buf; -- offset = roundup(offset + trx->length, blocksize); -- /* Next loop iteration will increase the offset */ -- offset -= blocksize; -+ last_subpart = max3(trx->offset[0], trx->offset[1], -+ trx->offset[2]); -+ trx_size = max(trx->length, last_subpart + blocksize); -+ -+ /* -+ * Skip the TRX data. Decrease offset by block size as -+ * the next loop iteration will increase it. -+ */ -+ offset += roundup(trx_size, blocksize) - blocksize; - continue; - } - -- cgit v1.2.3