[PATCH iproute2] tc/lexer: let quotes actually start strings

[PATCH iproute2] tc/lexer: let quotes actually start strings

[Wolfgang Bumiller]

The lexer will go with the longest match, so previously
the starting double quotes of a string would be swallowed by
the [^ \t\r\n()]+ pattern leaving the user no way to
actually use strings with escape sequences.
Fix this by not allowing this case to start with double
quotes.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
---
(Resent as separate thread)
 tc/emp_ematch.l | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tc/emp_ematch.l b/tc/emp_ematch.l
index dc106759..d7a99304 100644
--- a/tc/emp_ematch.l
+++ b/tc/emp_ematch.l
@@ -137,7 +137,7 @@
 ")"					{
 						return yylval.i = *yytext;
 					}
-[^ \t\r\n()]+				{
+[^" \t\r\n()][^ \t\r\n()]*		{
 						yylval.b = bstr_alloc(yytext);
 						if (yylval.b == NULL)
 							return ERROR;
-- 
2.11.0

Re: [PATCH iproute2] tc/lexer: let quotes actually start strings

[Stephen Hemminger]

On Mon, 22 Jan 2018 11:53:46 +0100
Wolfgang Bumiller <w.bumiller@proxmox.com> wrote:

> The lexer will go with the longest match, so previously
> the starting double quotes of a string would be swallowed by
> the [^ \t\r\n()]+ pattern leaving the user no way to
> actually use strings with escape sequences.
> Fix this by not allowing this case to start with double
> quotes.
> 
> Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
> ---

This is the same patch you posted earlier. It looked fine, just that
it needs some time for people on mailing list to review.

Re: [PATCH iproute2] tc/lexer: let quotes actually start strings

[Stephen Hemminger]

On Mon, 22 Jan 2018 11:53:46 +0100
Wolfgang Bumiller <w.bumiller@proxmox.com> wrote:

> The lexer will go with the longest match, so previously
> the starting double quotes of a string would be swallowed by
> the [^ \t\r\n()]+ pattern leaving the user no way to
> actually use strings with escape sequences.
> Fix this by not allowing this case to start with double
> quotes.
> 
> Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

Looks good, applied.
Don't think ematch is that widely used; or someone would have noticed.

[PATCH net+iproute2 0/2] nbyte, cmp and text filter fixups

[Wolfgang Bumiller]

The iproute2 part allows the the actual use of the already existing
quoted string parsing.

The kernel side fixes an oob read in em_nbyte and allows 'layer 0' in
cmp and nbyte (and em_text whose existence surprised me given that I did
not see it exposed via iproute2) to actually match layer 0 rather than
being the same as specifying layer 1.

I seem to have stumbled upon a layer of dust (says git-blame).
Trying to match mac addresses I felt that the examples found online
using the 'u32' filter were rather inconvenient, particularly given
that there's the 'nbyte' filter around that could just memcmp the
entire a byte sequence at once.

Wolfgang Bumiller (1; 2):
  tc/lexer: let quotes actually start strings

 tc/emp_ematch.l | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

  net: sched: em_nbyte: don't add the data offset twice
  net_sched: fix TCF_LAYER_LINK case in tcf_get_base_ptr

 include/net/pkt_cls.h | 2 +-
 net/sched/em_nbyte.c  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

-- 
2.11.0

[PATCH iproute2] tc/lexer: let quotes actually start strings

[Wolfgang Bumiller]

The lexer will go with the longest match, so previously
the starting double quotes of a string would be swallowed by
the [^ \t\r\n()]+ pattern leaving the user no way to
actually use strings with escape sequences.
Fix this by not allowing this case to start with double
quotes.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
---
 tc/emp_ematch.l | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tc/emp_ematch.l b/tc/emp_ematch.l
index dc106759..d7a99304 100644
--- a/tc/emp_ematch.l
+++ b/tc/emp_ematch.l
@@ -137,7 +137,7 @@
 ")"					{
 						return yylval.i = *yytext;
 					}
-[^ \t\r\n()]+				{
+[^" \t\r\n()][^ \t\r\n()]*		{
 						yylval.b = bstr_alloc(yytext);
 						if (yylval.b == NULL)
 							return ERROR;
-- 
2.11.0