6.14-stable review patch. If anyone has any objections, please let me know.
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From: Ido Schimmel idosch@nvidia.com
[ Upstream commit eaa517b77e63442260640d875f824d1111ca6569 ]
The 'read_write_len_ext' field in 'struct ethtool_cmis_cdb_cmd_args' stores the maximum number of bytes that can be read from or written to the Local Payload (LPL) page in a single multi-byte access.
Cited commit started overwriting this field with the maximum number of bytes that can be read from or written to the Extended Payload (LPL) pages in a single multi-byte access. Transceiver modules that support auto paging can advertise a number larger than 255 which is problematic as 'read_write_len_ext' is a 'u8', resulting in the number getting truncated and firmware flashing failing [1].
Fix by ignoring the maximum EPL access size as the kernel does not currently support auto paging (even if the transceiver module does) and will not try to read / write more than 128 bytes at once.
[1] Transceiver module firmware flashing started for device enp177s0np0 Transceiver module firmware flashing in progress for device enp177s0np0 Progress: 0% Transceiver module firmware flashing encountered an error for device enp177s0np0 Status message: Write FW block EPL command failed, LPL length is longer than CDB read write length extension allows.
Fixes: 9a3b0d078bd8 ("net: ethtool: Add support for writing firmware blocks using EPL payload") Reported-by: Damodharam Ammepalli damodharam.ammepalli@broadcom.com Closes: https://lore.kernel.org/netdev/20250402183123.321036-3-michael.chan@broadcom... Tested-by: Damodharam Ammepalli damodharam.ammepalli@broadcom.com Signed-off-by: Ido Schimmel idosch@nvidia.com Reviewed-by: Damodharam Ammepalli damodharam.ammepalli@broadcom.com Reviewed-by: Petr Machata petrm@nvidia.com Link: https://patch.msgid.link/20250409112440.365672-1-idosch@nvidia.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/ethtool/cmis.h | 1 - net/ethtool/cmis_cdb.c | 18 +++--------------- 2 files changed, 3 insertions(+), 16 deletions(-)
diff --git a/net/ethtool/cmis.h b/net/ethtool/cmis.h index 1e790413db0e8..4a9a946cabf05 100644 --- a/net/ethtool/cmis.h +++ b/net/ethtool/cmis.h @@ -101,7 +101,6 @@ struct ethtool_cmis_cdb_rpl { };
u32 ethtool_cmis_get_max_lpl_size(u8 num_of_byte_octs); -u32 ethtool_cmis_get_max_epl_size(u8 num_of_byte_octs);
void ethtool_cmis_cdb_compose_args(struct ethtool_cmis_cdb_cmd_args *args, enum ethtool_cmis_cdb_cmd_id cmd, u8 *lpl, diff --git a/net/ethtool/cmis_cdb.c b/net/ethtool/cmis_cdb.c index d159dc121bde5..0e2691ccb0df3 100644 --- a/net/ethtool/cmis_cdb.c +++ b/net/ethtool/cmis_cdb.c @@ -16,15 +16,6 @@ u32 ethtool_cmis_get_max_lpl_size(u8 num_of_byte_octs) return 8 * (1 + min_t(u8, num_of_byte_octs, 15)); }
-/* For accessing the EPL field on page 9Fh, the allowable length extension is - * min(i, 255) byte octets where i specifies the allowable additional number of - * byte octets in a READ or a WRITE. - */ -u32 ethtool_cmis_get_max_epl_size(u8 num_of_byte_octs) -{ - return 8 * (1 + min_t(u8, num_of_byte_octs, 255)); -} - void ethtool_cmis_cdb_compose_args(struct ethtool_cmis_cdb_cmd_args *args, enum ethtool_cmis_cdb_cmd_id cmd, u8 *lpl, u8 lpl_len, u8 *epl, u16 epl_len, @@ -33,19 +24,16 @@ void ethtool_cmis_cdb_compose_args(struct ethtool_cmis_cdb_cmd_args *args, { args->req.id = cpu_to_be16(cmd); args->req.lpl_len = lpl_len; - if (lpl) { + if (lpl) memcpy(args->req.payload, lpl, args->req.lpl_len); - args->read_write_len_ext = - ethtool_cmis_get_max_lpl_size(read_write_len_ext); - } if (epl) { args->req.epl_len = cpu_to_be16(epl_len); args->req.epl = epl; - args->read_write_len_ext = - ethtool_cmis_get_max_epl_size(read_write_len_ext); }
args->max_duration = max_duration; + args->read_write_len_ext = + ethtool_cmis_get_max_lpl_size(read_write_len_ext); args->msleep_pre_rpl = msleep_pre_rpl; args->rpl_exp_len = rpl_exp_len; args->flags = flags;