This is a note to let you know that I've just added the patch titled scsi: ipr: Work around fortify-string warning to the 5.10-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: scsi-ipr-work-around-fortify-string-warning.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 9484bdd45d431ff66453800f65ace57bd2a324fb Author: Arnd Bergmann <arnd@xxxxxxxx> Date: Tue Feb 14 14:28:08 2023 +0100 scsi: ipr: Work around fortify-string warning [ Upstream commit ee4e7dfe4ffc9ca50c6875757bd119abfe22b5c5 ] The ipr_log_vpd_compact() function triggers a fortified memcpy() warning about a potential string overflow with all versions of clang: In file included from drivers/scsi/ipr.c:43: In file included from include/linux/string.h:254: include/linux/fortify-string.h:520:4: error: call to '__write_overflow_field' declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning] __write_overflow_field(p_size_field, size); ^ include/linux/fortify-string.h:520:4: error: call to '__write_overflow_field' declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning] 2 errors generated. I don't see anything actually wrong with the function, but this is the only instance I can reproduce of the fortification going wrong in the kernel at the moment, so the easiest solution may be to rewrite the function into something that does not trigger the warning. Instead of having a combined buffer for vendor/device/serial strings, use three separate local variables and just truncate the whitespace individually. Link: https://lore.kernel.org/r/20230214132831.2118392-1-arnd@xxxxxxxxxx Cc: Kees Cook <keescook@xxxxxxxxxxxx> Fixes: 8cf093e275d0 ("[SCSI] ipr: Improved dual adapter errors") Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> Acked-by: Brian King <brking@xxxxxxxxxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c index a5e6fbd86ad45..8c376736a8f51 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -1516,23 +1516,22 @@ static void ipr_process_ccn(struct ipr_cmnd *ipr_cmd) } /** - * strip_and_pad_whitespace - Strip and pad trailing whitespace. - * @i: index into buffer - * @buf: string to modify + * strip_whitespace - Strip and pad trailing whitespace. + * @i: size of buffer + * @buf: string to modify * - * This function will strip all trailing whitespace, pad the end - * of the string with a single space, and NULL terminate the string. + * This function will strip all trailing whitespace and + * NUL terminate the string. * - * Return value: - * new length of string **/ -static int strip_and_pad_whitespace(int i, char *buf) +static void strip_whitespace(int i, char *buf) { + if (i < 1) + return; + i--; while (i && buf[i] == ' ') i--; - buf[i+1] = ' '; - buf[i+2] = '\0'; - return i + 2; + buf[i+1] = '\0'; } /** @@ -1547,19 +1546,21 @@ static int strip_and_pad_whitespace(int i, char *buf) static void ipr_log_vpd_compact(char *prefix, struct ipr_hostrcb *hostrcb, struct ipr_vpd *vpd) { - char buffer[IPR_VENDOR_ID_LEN + IPR_PROD_ID_LEN + IPR_SERIAL_NUM_LEN + 3]; - int i = 0; + char vendor_id[IPR_VENDOR_ID_LEN + 1]; + char product_id[IPR_PROD_ID_LEN + 1]; + char sn[IPR_SERIAL_NUM_LEN + 1]; - memcpy(buffer, vpd->vpids.vendor_id, IPR_VENDOR_ID_LEN); - i = strip_and_pad_whitespace(IPR_VENDOR_ID_LEN - 1, buffer); + memcpy(vendor_id, vpd->vpids.vendor_id, IPR_VENDOR_ID_LEN); + strip_whitespace(IPR_VENDOR_ID_LEN, vendor_id); - memcpy(&buffer[i], vpd->vpids.product_id, IPR_PROD_ID_LEN); - i = strip_and_pad_whitespace(i + IPR_PROD_ID_LEN - 1, buffer); + memcpy(product_id, vpd->vpids.product_id, IPR_PROD_ID_LEN); + strip_whitespace(IPR_PROD_ID_LEN, product_id); - memcpy(&buffer[i], vpd->sn, IPR_SERIAL_NUM_LEN); - buffer[IPR_SERIAL_NUM_LEN + i] = '\0'; + memcpy(sn, vpd->sn, IPR_SERIAL_NUM_LEN); + strip_whitespace(IPR_SERIAL_NUM_LEN, sn); - ipr_hcam_err(hostrcb, "%s VPID/SN: %s\n", prefix, buffer); + ipr_hcam_err(hostrcb, "%s VPID/SN: %s %s %s\n", prefix, + vendor_id, product_id, sn); } /**