On 13 January 2017 at 11:34, Jan Vesely <jan.vesely@xxxxxxxxxxx> wrote: > On Thu, 2017-01-12 at 18:16 -0800, Nicholas Miell wrote: >> From 714d07f600db39498c87d7816f4dd3a7e6d9bbca Mon Sep 17 00:00:00 2001 >> From: Nicholas Miell <nmiell@xxxxxxxxx> >> Date: Thu, 12 Jan 2017 15:43:07 -0800 >> Subject: [PATCH libdrm] xf86drm: fix valgrind warning in drmParsePciBusInfo >> >> The current implementation reads (up to) 513 bytes, overwrites the 513th >> byte with '\0' and then passes the buffer off to strstr() and sscanf() >> without ever initializing the middle bytes. This causes valgrind >> warnings and potentially fails to parse PCI_SLOT_NAME if the uevent is >> unexpectedly large. > > a simpler fix should also get rid of the valgrind warning: > > - ret = read(fd, data, sizeof(data)); > - data[sizeof(data)-1] = '\0'; > + ret = read(fd, data, sizeof(data) - 1); > close(fd); > if (ret < 0) > return -errno > + data[ret] = '\0'; > We had this (better imho) patch a week or so ago. In either case the issue is virtually since (iirc) if the string is malformed we'll bail out either way. > > I think that dynamic memory allocation is still a more robust approach. > Yes that might be the better solution, or one could even use getline(). The latter might be pushing it's only POSIX 2008. Thanks Emil _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
