[ltt-dev] Bug in add_marker (marker.c)

[Damien COTTIER]

Hi all,

While creating my own probes, I've observed that I get format mismatch error... While digging into the executed code I observe that my format (stored in a marker_entry) was overwritten by a new allocated structure. Finally I found that in add_marker function the format pointer seems to be set to the wrong position:
e->format = &e->name[channel_len + name_len];
while the proper assignment should be
e->format = &e->name[name_len];

indead:

size_t channel_len = strlen(channel) + 1;
size_t name_len = strlen(name) + 1;
...
size_t format_len ...= strlen(format) + 1;

and

struct marker_entry {
....
    char channel[0];        /* Contains channel'\0'name'\0'format'\0' *     /

};

...

e = kmalloc(sizeof(struct marker_entry)
      + channel_len + name_len + format_len,
      GFP_KERNEL);
....
e->name = &e->channel[channel_len];

Rgds,
Damien COTTIER.



[cid:457404209 at 21072010-2D25]

Damien COTTIER
Application and Architecture Engineer

ST-Ericsson
Platform and Sytem Architecture
12 rue Jules Horowitz
38019, Grenoble
France
www.stericsson.com<http://www.stericsson.com/>

        Office: +33 (0)4 76 58 65 59
Mobile: -----
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Email: damien.cottier at stericsson.com<mailto:damien.cottier at stericsson.com>


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