This is a note to let you know that I've just added the patch titled mtd: parsers: qcom: Fix kernel panic on skipped partition to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mtd-parsers-qcom-fix-kernel-panic-on-skipped-partiti.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ef714afc040ce98367efcc5a66292f7749ae68de Author: Ansuel Smith <ansuelsmth@xxxxxxxxx> Date: Sun Jan 16 04:22:10 2022 +0100 mtd: parsers: qcom: Fix kernel panic on skipped partition [ Upstream commit 65d003cca335cabc0160d3cd7daa689eaa9dd3cd ] In the event of a skipped partition (case when the entry name is empty) the kernel panics in the cleanup function as the name entry is NULL. Rework the parser logic by first checking the real partition number and then allocate the space and set the data for the valid partitions. The logic was also fundamentally wrong as with a skipped partition, the parts number returned was incorrect by not decreasing it for the skipped partitions. Fixes: 803eb124e1a6 ("mtd: parsers: Add Qcom SMEM parser") Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx> Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> Link: https://lore.kernel.org/linux-mtd/20220116032211.9728-1-ansuelsmth@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/mtd/parsers/qcomsmempart.c b/drivers/mtd/parsers/qcomsmempart.c index 06a818cd2433f..f4fc7635c1f39 100644 --- a/drivers/mtd/parsers/qcomsmempart.c +++ b/drivers/mtd/parsers/qcomsmempart.c @@ -58,11 +58,11 @@ static int parse_qcomsmem_part(struct mtd_info *mtd, const struct mtd_partition **pparts, struct mtd_part_parser_data *data) { + size_t len = SMEM_FLASH_PTABLE_HDR_LEN; + int ret, i, j, tmpparts, numparts = 0; struct smem_flash_pentry *pentry; struct smem_flash_ptable *ptable; - size_t len = SMEM_FLASH_PTABLE_HDR_LEN; struct mtd_partition *parts; - int ret, i, numparts; char *name, *c; if (IS_ENABLED(CONFIG_MTD_SPI_NOR_USE_4K_SECTORS) @@ -87,8 +87,8 @@ static int parse_qcomsmem_part(struct mtd_info *mtd, } /* Ensure that # of partitions is less than the max we have allocated */ - numparts = le32_to_cpu(ptable->numparts); - if (numparts > SMEM_FLASH_PTABLE_MAX_PARTS_V4) { + tmpparts = le32_to_cpu(ptable->numparts); + if (tmpparts > SMEM_FLASH_PTABLE_MAX_PARTS_V4) { pr_err("Partition numbers exceed the max limit\n"); return -EINVAL; } @@ -116,11 +116,17 @@ static int parse_qcomsmem_part(struct mtd_info *mtd, return PTR_ERR(ptable); } + for (i = 0; i < tmpparts; i++) { + pentry = &ptable->pentry[i]; + if (pentry->name[0] != '\0') + numparts++; + } + parts = kcalloc(numparts, sizeof(*parts), GFP_KERNEL); if (!parts) return -ENOMEM; - for (i = 0; i < numparts; i++) { + for (i = 0, j = 0; i < tmpparts; i++) { pentry = &ptable->pentry[i]; if (pentry->name[0] == '\0') continue; @@ -135,24 +141,25 @@ static int parse_qcomsmem_part(struct mtd_info *mtd, for (c = name; *c != '\0'; c++) *c = tolower(*c); - parts[i].name = name; - parts[i].offset = le32_to_cpu(pentry->offset) * mtd->erasesize; - parts[i].mask_flags = pentry->attr; - parts[i].size = le32_to_cpu(pentry->length) * mtd->erasesize; + parts[j].name = name; + parts[j].offset = le32_to_cpu(pentry->offset) * mtd->erasesize; + parts[j].mask_flags = pentry->attr; + parts[j].size = le32_to_cpu(pentry->length) * mtd->erasesize; pr_debug("%d: %s offs=0x%08x size=0x%08x attr:0x%08x\n", i, pentry->name, le32_to_cpu(pentry->offset), le32_to_cpu(pentry->length), pentry->attr); + j++; } pr_debug("SMEM partition table found: ver: %d len: %d\n", - le32_to_cpu(ptable->version), numparts); + le32_to_cpu(ptable->version), tmpparts); *pparts = parts; return numparts; out_free_parts: - while (--i >= 0) - kfree(parts[i].name); + while (--j >= 0) + kfree(parts[j].name); kfree(parts); *pparts = NULL;