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| author | Joseph Myers <joseph@codesourcery.com> | 2017-12-18 18:50:40 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2017-12-18 18:50:40 +0000 |
| commit | 49b036bce9f021ae994a85aee8b410d20b29c8b7 (patch) | |
| tree | f0100e6d1378252d9cb40f96982b245ab69a657c /nscd | |
| parent | c85c564d1442f0bc09a6c80fca025f004e12d044 (diff) | |
| download | glibc-49b036bce9f021ae994a85aee8b410d20b29c8b7.tar.gz glibc-49b036bce9f021ae994a85aee8b410d20b29c8b7.tar.xz glibc-49b036bce9f021ae994a85aee8b410d20b29c8b7.zip | |
Fix nscd readlink argument aliasing (bug 22446).
Current GCC mainline detects that nscd calls readlink with the same buffer for both input and output, which is not valid (those arguments are both restrict-qualified in POSIX). This patch makes it use a separate buffer for readlink's input (with a size that is sufficient to avoid truncation, so there should be no problems with warnings about possible truncation, though not strictly minimal, but much smaller than the buffer for output) to avoid this problem. Tested compilation for aarch64-linux-gnu with build-many-glibcs.py. [BZ #22446] * nscd/connections.c (handle_request) [SO_PEERCRED]: Use separate buffers for readlink input and output.
Diffstat (limited to 'nscd')
| -rw-r--r-- | nscd/connections.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/nscd/connections.c b/nscd/connections.c index cc1ed72077..dab722dcb2 100644 --- a/nscd/connections.c +++ b/nscd/connections.c @@ -1077,14 +1077,15 @@ cannot handle old request version %d; current version is %d"), if (debug_level > 0) { #ifdef SO_PEERCRED + char pbuf[sizeof ("/proc//exe") + 3 * sizeof (long int)]; # ifdef PATH_MAX char buf[PATH_MAX]; # else char buf[4096]; # endif - snprintf (buf, sizeof (buf), "/proc/%ld/exe", (long int) pid); - ssize_t n = readlink (buf, buf, sizeof (buf) - 1); + snprintf (pbuf, sizeof (pbuf), "/proc/%ld/exe", (long int) pid); + ssize_t n = readlink (pbuf, buf, sizeof (buf) - 1); if (n <= 0) dbg_log (_("\ |