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devip: do not lock selftab in ipselftabread(), remove unused fields from Ipself

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the Ipselftab is designed to not require locking on read
operation. locking the selftab in ipselftabread() risks
deadlock when accessing the user buffer creates a fault.

remove unused fields from the Ipself struct.
This commit is contained in:
cinap_lenrek 2019-05-12 01:20:21 +02:00
parent bf4f158707
commit 157d7ebdbd
2 changed files with 3 additions and 7 deletions
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4
sys/src/9/ip/ip.h
View file

@ -274,9 +274,9 @@ struct Iplink
Ipself *self; Ipself *self;
Iplifc *lifc; Iplifc *lifc;
Iplink *selflink; /* next link for this local address */ Iplink *selflink; /* next link for this local address */
Iplink *lifclink; /* next link for this ifc */ Iplink *lifclink; /* next link for this lifc */
ulong expire;
Iplink *next; /* free list */ Iplink *next; /* free list */
ulong expire;
int ref; int ref;
}; };

6
sys/src/9/ip/ipifc.c
View file

@ -26,12 +26,10 @@ Medium *media[Maxmedia] = { 0 };
struct Ipself struct Ipself
{ {
uchar a[IPaddrlen]; uchar a[IPaddrlen];
Ipself *hnext; /* next address in the hash table */ Ipself *next; /* next address in the hash table */
Iplink *link; /* binding twixt Ipself and Ipifc */ Iplink *link; /* binding twixt Ipself and Ipifc */
ulong expire; ulong expire;
uchar type; /* type of address */ uchar type; /* type of address */
int ref;
Ipself *next; /* free list */
}; };
struct Ipselftab struct Ipselftab
@ -1100,7 +1098,6 @@ ipselftabread(Fs *f, char *cp, ulong offset, int n)
m = 0; m = 0;
off = offset; off = offset;
qlock(f->self);
for(i = 0; i < NHASH && m < n; i++){ for(i = 0; i < NHASH && m < n; i++){
for(p = f->self->hash[i]; p != nil && m < n; p = p->next){ for(p = f->self->hash[i]; p != nil && m < n; p = p->next){
nifc = 0; nifc = 0;
@ -1115,7 +1112,6 @@ ipselftabread(Fs *f, char *cp, ulong offset, int n)
} }
} }
} }
qunlock(f->self);
return m; return m;
} }