_p and _w are adjusted to account for the partial write (if any).
However, _p and _w should not be unconditionally adjusted and should only
be changed when we actually wrote some bytes, or the accumulated accounting
error will eventually result in a heap buffer overflow.
Reported by: adrian and alfred (Norse Corporation)
Security: FreeBSD-SA-14:27.stdio
Security: CVE-2014-8611
For consistency with r268985 for fputs.c, assign iov_len
first, avoiding the cast to uio_resid (int in stdio)
from degrading the value.
We currently don't support lengths higher than INT_MAX so
this change is little more than cosmetic.
MFC after: 3 days
Check for __SAPP flag before calling sflush. This avoids
performance degradation compared to the previous approach.
Submitted by: ache
MFC after: 2 weeks
Use EBADF instead of EINVAL when working around incorrect O_ACCMODE.
Phabric: D442
Obtained from: Apple Inc. (Libc 997.90.3)
Reviewed by: jilles
MFC after: 1 week
This has small changes to what Apple uses for compliance
with SUSv3. The changes cause no secondary effects in the
gnulib tests (we pass them).
Obtained from: Apple Inc. (Libc 997.90.3 with changes)
Reviewed by: bde
Phabric: D440
Update the manpage to reflect this change.
- Always set the current position to the first null-byte when opening in append
mode. This makes the implementation compatible with glibc's. Update the test
suite.
Reported by: pho
Approved by: cognet
An execute-only fd (opened with O_EXEC) allows neither read() nor write()
and is therefore incompatible with all stdio modes. Therefore, the [EINVAL]
error applies.
Also adjust the similar check in freopen() with a NULL path, even though
this checks an fd which is already from a FILE.
if not already defined. This allows building libc from outside of
lib/libc using a reach-over makefile.
A typical use-case is to build a standard ILP32 version and a COMPAT32
version in a single iteration by building the COMPAT32 version using a
reach-over makefile.
Obtained from: Juniper Networks, Inc.
Austin Group issue #411 requires 'e' to be accepted before and after 'x',
and encourages accepting the characters in any order, except the initial
'r', 'w' or 'a'.
Given that glibc accepts the characters after r/w/a in any order and that
diagnosing this problem may be hard, change our libc to behave that way as
well.
This ensures strerror() and friends continue to work correctly even if a
(non-PIE) executable linked against an older libc imports sys_errlist (which
causes sys_errlist to refer to the executable's copy with a size fixed when
that executable was linked).
The executable's use of sys_errlist remains broken because it uses the
current value of sys_nerr and may access past the bounds of the array.
Different from the message "Using sys_errlist from executables is not
ABI-stable" on freebsd-arch, this change does not affect the static library.
There seems no reason to prevent overriding the error messages in the static
library.
mktemp(), mkstemp() and mkdtemp() are available in standard <stdlib.h> and
also in <unistd.h>. Encourage use of the former by listing it in the
synopsis.
routines provide write-only stdio FILE objects that store their data in a
dynamically allocated buffer. They are a string builder interface somewhat
akin to a completely dynamic sbuf.
Reviewed by: bde, jilles (earlier versions)
MFC after: 1 month
with the user's namespace.
- Correct size and position variables type from long to size_t.
- Do not set errno to ENOMEM on malloc failure, as malloc already does so.
- Implement the concept of "buffer data length", which mandates what SEEK_END
refers to and the allowed extent for a read.
- Use NULL as read-callback if the buffer is opened in write-only mode.
Conversely, use NULL as write-callback when opened in read-only mode.
- Implement the handling of the ``b'' character in the mode argument. A binary
buffer differs from a text buffer (default mode if ``b'' is omitted) in that
NULL bytes are never appended to writes and that the "buffer data length"
equals to the size of the buffer.
- Remove shall from the man page. Use indicative instead. Also, specify that
the ``b'' flag does not conform with POSIX but is supported by glibc.
- Update the regression test so that the ``b'' functionality and the "buffer
data length" concepts are tested.
- Minor style(9) corrections.
Suggested by: jilles
Reviewed by: cognet
Approved by: cognet
This commit adds a new mode option 'e' that must follow any 'b', '+' and/or
'x' options. C11 is clear about the 'x' needing to follow 'b' and/or '+' and
that is what we implement; therefore, require a strict position for 'e' as
well.
For freopen() with a non-NULL path argument and fopen(), the close-on-exec
flag is set iff the 'e' mode option is specified. For freopen() with a NULL
path argument and fdopen(), the close-on-exec flag is turned on if the 'e'
mode option is specified and remains unchanged otherwise.
Although the same behaviour for fopen() can be obtained by open(O_CLOEXEC)
and fdopen(), this needlessly complicates the calling code.
Apart from the ordering requirement, the new option matches glibc.
PR: kern/169320
this fflush may fail to write data in the buffer.
PR: kern/137819
Submitted by: Eric Blake <ebb9@byu.net>
Reviewed by: theraven
Approved by: cperciva
MFC after: 2 weeks
The typical case was:
static __inline int
convert_ccl(FILE *fp, char * __restrict p, [...])
{
[...]
if (p == SUPPRESS_PTR) {
[...]
} else {
[...]
}
[...]
}
This qualifier says that the pointer is the only one at that time
pointing to the resource.
Here, clang considers that "p" will never match "SUPPRESS_PTR" and
optimize the if{} block out. This leads to segfaults in programs calling
vfscanf(3) and vfwscanf(3) with just the format string (no arguments
following it).
The following softwares were reported to abort with segmentation fault
and this patch fixes it:
o cmake
o smartd
o devel/ORBit2
dim@ opened an LLVM PR to discuss this clang optimization:
http://llvm.org/bugs/show_bug.cgi?id=12656
Tested by: bsam@
