| Message ID | 20211115144846.GA12078@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v5] Add payload to be 32-bit aligned to fix dropped packets | expand |
On Mon, 15 Nov 2021 20:18:46 +0530 Kumar Thangavel wrote: > @@ -213,12 +215,16 @@ static int ncsi_cmd_handler_oem(struct sk_buff *skb, > { > struct ncsi_cmd_oem_pkt *cmd; > unsigned int len; > + /* NC-SI spec DSP_0222_1.2.0, section 8.2.2.2 > + * requires payload to be padded with 0 to > + * 32-bit boundary before the checksum field. > + * Ensure the padding bytes are accounted for in > + * skb allocation > + */ > > + unsigned short payload = ALIGN(nca->payload, 4); > len = sizeof(struct ncsi_cmd_pkt_hdr) + 4; This looks like mixing code and declarations. If a piece of code is important enough to warrant a comment it should not be placed as variable init. > @@ -272,6 +278,7 @@ static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca) > struct net_device *dev = nd->dev; > int hlen = LL_RESERVED_SPACE(dev); > int tlen = dev->needed_tailroom; > + int payload; > int len = hlen + tlen; > struct sk_buff *skb; > struct ncsi_request *nr; > @@ -281,14 +288,14 @@ static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca) > return NULL; > > /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum. > + * Payload needs padding so that the checksum field following payload is > + * aligned to 32-bit boundary. > * The packet needs padding if its payload is less than 26 bytes to > * meet 64 bytes minimal ethernet frame length. > */ > len += sizeof(struct ncsi_cmd_pkt_hdr) + 4; > - if (nca->payload < 26) > - len += 26; > - else > - len += nca->payload; > + payload = ALIGN(nca->payload, 4); > + len += max(payload, padding_bytes); payload is int here, and padding_bytes is unsigned short, you either have to use max_t() or change the types to agree.
Hi Kumar,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v5.16-rc1 next-20211115]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Kumar-Thangavel/Add-payload-to-be-32-bit-aligned-to-fix-dropped-packets/20211115-224945
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 8ab774587903771821b59471cc723bba6d893942
config: riscv-randconfig-r026-20211115 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project fbe72e41b99dc7994daac300d208a955be3e4a0a)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install riscv cross compiling tool for clang build
# apt-get install binutils-riscv64-linux-gnu
# https://github.com/0day-ci/linux/commit/dc2cde90f4de825ff92f0ad81bc70e132c6ad6ec
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Kumar-Thangavel/Add-payload-to-be-32-bit-aligned-to-fix-dropped-packets/20211115-224945
git checkout dc2cde90f4de825ff92f0ad81bc70e132c6ad6ec
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=riscv
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> net/ncsi/ncsi-cmd.c:298:9: warning: comparison of distinct pointer types ('typeof (payload) *' (aka 'int *') and 'typeof (padding_bytes) *' (aka 'const unsigned short *')) [-Wcompare-distinct-pointer-types]
len += max(payload, padding_bytes);
^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:52:19: note: expanded from macro 'max'
#define max(x, y) __careful_cmp(x, y, >)
^~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp'
__builtin_choose_expr(__safe_cmp(x, y), \
^~~~~~~~~~~~~~~~
include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp'
(__typecheck(x, y) && __no_side_effects(x, y))
^~~~~~~~~~~~~~~~~
include/linux/minmax.h:20:28: note: expanded from macro '__typecheck'
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~
1 warning generated.
vim +298 net/ncsi/ncsi-cmd.c
273
274 static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca)
275 {
276 struct ncsi_dev_priv *ndp = nca->ndp;
277 struct ncsi_dev *nd = &ndp->ndev;
278 struct net_device *dev = nd->dev;
279 int hlen = LL_RESERVED_SPACE(dev);
280 int tlen = dev->needed_tailroom;
281 int payload;
282 int len = hlen + tlen;
283 struct sk_buff *skb;
284 struct ncsi_request *nr;
285
286 nr = ncsi_alloc_request(ndp, nca->req_flags);
287 if (!nr)
288 return NULL;
289
290 /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum.
291 * Payload needs padding so that the checksum field following payload is
292 * aligned to 32-bit boundary.
293 * The packet needs padding if its payload is less than 26 bytes to
294 * meet 64 bytes minimal ethernet frame length.
295 */
296 len += sizeof(struct ncsi_cmd_pkt_hdr) + 4;
297 payload = ALIGN(nca->payload, 4);
> 298 len += max(payload, padding_bytes);
299
300 /* Allocate skb */
301 skb = alloc_skb(len, GFP_ATOMIC);
302 if (!skb) {
303 ncsi_free_request(nr);
304 return NULL;
305 }
306
307 nr->cmd = skb;
308 skb_reserve(skb, hlen);
309 skb_reset_network_header(skb);
310
311 skb->dev = dev;
312 skb->protocol = htons(ETH_P_NCSI);
313
314 return nr;
315 }
316
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff --git a/net/ncsi/ncsi-cmd.c b/net/ncsi/ncsi-cmd.c index ba9ae482141b..9571bb4dd991 100644 --- a/net/ncsi/ncsi-cmd.c +++ b/net/ncsi/ncsi-cmd.c @@ -18,6 +18,8 @@ #include "internal.h" #include "ncsi-pkt.h" +const unsigned short padding_bytes = 26; + u32 ncsi_calculate_checksum(unsigned char *data, int len) { u32 checksum = 0; @@ -213,12 +215,16 @@ static int ncsi_cmd_handler_oem(struct sk_buff *skb, { struct ncsi_cmd_oem_pkt *cmd; unsigned int len; + /* NC-SI spec DSP_0222_1.2.0, section 8.2.2.2 + * requires payload to be padded with 0 to + * 32-bit boundary before the checksum field. + * Ensure the padding bytes are accounted for in + * skb allocation + */ + unsigned short payload = ALIGN(nca->payload, 4); len = sizeof(struct ncsi_cmd_pkt_hdr) + 4; - if (nca->payload < 26) - len += 26; - else - len += nca->payload; + len += max(payload, padding_bytes); cmd = skb_put_zero(skb, len); memcpy(&cmd->mfr_id, nca->data, nca->payload); @@ -272,6 +278,7 @@ static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca) struct net_device *dev = nd->dev; int hlen = LL_RESERVED_SPACE(dev); int tlen = dev->needed_tailroom; + int payload; int len = hlen + tlen; struct sk_buff *skb; struct ncsi_request *nr; @@ -281,14 +288,14 @@ static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca) return NULL; /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum. + * Payload needs padding so that the checksum field following payload is + * aligned to 32-bit boundary. * The packet needs padding if its payload is less than 26 bytes to * meet 64 bytes minimal ethernet frame length. */ len += sizeof(struct ncsi_cmd_pkt_hdr) + 4; - if (nca->payload < 26) - len += 26; - else - len += nca->payload; + payload = ALIGN(nca->payload, 4); + len += max(payload, padding_bytes); /* Allocate skb */ skb = alloc_skb(len, GFP_ATOMIC);
Update NC-SI command handler (both standard and OEM) to take into account of payload paddings in allocating skb (in case of payload size is not 32-bit aligned). The checksum field follows payload field, without taking payload padding into account can cause checksum being truncated, leading to dropped packets. Fixes: fb4ee67529ff ("net/ncsi: Add NCSI OEM command support") Signed-off-by: Kumar Thangavel <thangavel.k@hcl.com> Acked-by: Samuel Mendoza-Jonas <sam@mendozajonas.com> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> --- v5: - Added Fixes tag - Added const variable for padding_bytes v4: - Used existing macro for max function v3: - Added Macro for MAX - Fixed the missed semicolon v2: - Added NC-SI spec version and section - Removed blank line - corrected spellings v1: - Initial draft --- --- net/ncsi/ncsi-cmd.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-)