libosmo-netif[master]: src: _snprintf() helper functions always nul-terminate buffers

[Pau Espin Pedrol]

Patch Set 1: Code-Review-1

(2 comments)

https://gerrit.osmocom.org/#/c/3830/1/src/osmux.c
File src/osmux.c:

Line 941: 	/* This _snprintf() variant always nul-terminates the buffer. */
I still don't get why you say at least some variants of snprintf don't contain nul-terminated buffers.


Line 945: 		buf[offset] = '\0';
in a given case, size=50 and offset=60 (buffer too small to contain everything) ---> buffer overflow.

You probably mean here: buf[size-1] = '\0'; (and still need to check size>0).

You probably need something like:

if (size) {
 if (offset >= size) {
     if(buf[size-1] != '\0')
       offset--;
     buf[size-1]  = '\0';
 } else {
    buf[offset] = '\0';
 }
}


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Gerrit-MessageType: comment
Gerrit-Change-Id: I97e517f2d98e83894ea707c63489559302ff6bd2
Gerrit-PatchSet: 1
Gerrit-Project: libosmo-netif
Gerrit-Branch: master
Gerrit-Owner: Pablo Neira Ayuso <pablo at gnumonks.org>
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: Pau Espin Pedrol <pespin at sysmocom.de>
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