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| author | Konrad Sewiłło-Jopek <kjopek@gmail.com> | 2022-08-08 16:25:48 +0000 |
|---|---|---|
| committer | Mark Johnston <markj@FreeBSD.org> | 2022-08-09 20:01:13 +0000 |
| commit | 7dfe949791e764115dda17ec6b21fba2e0a86a2e (patch) | |
| tree | 7b0ee0bf55e71b5cad67186e97ad6eee7c39e49f | |
| parent | 0c88ecaa12555cfea0395abdb0ffac9b3e0f3204 (diff) | |
| download | src-7dfe949791e7.tar.gz src-7dfe949791e7.zip | |
lib9p: Remove potential buffer overwrite in l9p_puqids()
Structure l9p_f_wralk reserves at most L9P_MAX_WELEM entries
and that number actually set the maximum we can safely use.
Approved by: so
Security: FreeBSD-SA-22:12.lib9p
PR: 265385
Reviewed by: markj
(cherry picked from commit 2dd83b3f0507fc7bc64b908fb88f285a3b9663c8)
(cherry picked from commit c536045c51da78a85138e963d3b7e13a547713c9)
| -rw-r--r-- | contrib/lib9p/pack.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/contrib/lib9p/pack.c b/contrib/lib9p/pack.c index 88f0ccb4ad73..cf0ae9111b76 100644 --- a/contrib/lib9p/pack.c +++ b/contrib/lib9p/pack.c @@ -343,13 +343,17 @@ l9p_puqids(struct l9p_message *msg, uint16_t *num, struct l9p_qid *qids) ssize_t ret, r; r = l9p_pu16(msg, num); - if (r > 0) { - for (i = 0, lim = *num; i < lim; i++) { - ret = l9p_puqid(msg, &qids[i]); - if (ret < 0) - return (-1); - r += ret; - } + if (r <= 0) + return (r); + + if (*num > L9P_MAX_WELEM) + return (-1); + + for (i = 0, lim = *num; i < lim; i++) { + ret = l9p_puqid(msg, &qids[i]); + if (ret < 0) + return (-1); + r += ret; } return (r); } |