Commit Graph

46 Commits

Author SHA1 Message Date
Daniel Micay
4200e260d2 fix the mremap signature
The mremap definition was incorrect (unsigned long instead of int) and
it was missing the optional new_address parameter.

Change-Id: Ib9d0675aaa098c21617cedc9b2b8cf267be3aec4
2015-11-06 13:14:43 -08:00
Elliott Hughes
6f4594d5dc Add preadv/pwritev.
Bug: http://b/12612572
Change-Id: I38ff2684d69bd0fe3f21b1d371b88fa60d5421cb
2015-08-26 14:48:55 -07:00
Elliott Hughes
b1304935b6 Hide accidentally-exposed __clock_nanosleep.
Bug: http://b/21858067
Change-Id: Iaa83a5e17cfff796aed4f641d0d14427614d9399
2015-06-15 19:39:04 -07:00
Elliott Hughes
be57a40d29 Add process_vm_readv and process_vm_writev.
Bug: http://b/21761353
Change-Id: Ic8ef3f241d62d2a4271fbc783c8af50257bac498
2015-06-10 17:24:20 -07:00
Nick Kralevich
e1d0810cd7 Add O_PATH support for flistxattr()
A continuation of commit 2825f10b7f.

Add O_PATH compatibility support for flistxattr(). This allows
a process to list out all the extended attributes associated with
O_PATH file descriptors.

Change-Id: Ie2285ac7ad2e4eac427ddba6c2d182d41b130f75
2015-06-06 11:25:41 -07:00
Nick Kralevich
2825f10b7f libc: Add O_PATH support for fgetxattr / fsetxattr
Support O_PATH file descriptors when handling fgetxattr and fsetxattr.
This avoids requiring file read access to pull extended attributes.

This is needed to support O_PATH file descriptors when calling
SELinux's fgetfilecon() call. In particular, this allows the querying
and setting of SELinux file context by using something like the following
code:

  int dirfd = open("/path/to/dir", O_DIRECTORY);
  int fd = openat(dirfd, "file", O_PATH | O_NOFOLLOW);
  char *context;
  fgetfilecon(fd, &context);

This change was motivated by a comment in
https://android-review.googlesource.com/#/c/152680/1/toys/posix/ls.c

Change-Id: Ic0cdf9f9dd0e35a63b44a4c4a08400020041eddf
2015-06-01 15:51:56 -07:00
Yabin Cui
40a8f214a5 Hide rt_sigqueueinfo.
Bug: 19358804
Change-Id: I38a53ad64c81d0eefdd1d24599e769fd8a477a56
2015-05-18 11:29:20 -07:00
Elliott Hughes
3391a9ff13 Simplify close(2) EINTR handling.
This doesn't affect code like Chrome that correctly ignores EINTR on
close, makes code that tries TEMP_FAILURE_RETRY work (where before it might
have closed a different fd and appeared to succeed, or had a bogus EBADF),
and makes "goto fail" code work (instead of mistakenly assuming that EINTR
means that the close failed).

Who loses? Anyone actively trying to detect that they caught a signal while
in close(2). I don't think those people exist, and I think they have better
alternatives available.

Bug: https://code.google.com/p/chromium/issues/detail?id=269623
Bug: http://b/20501816
Change-Id: I11e2f66532fe5d1b0082b2433212e24bdda8219b
2015-04-23 08:41:45 -07:00
Christopher Ferris
fa5faa0ce6 Make gensyscalls.py use the ALIAS_SYMBOL macro.
Change-Id: Ib94c0abb6fc85126ecc5ed3f1962b2b8b90b9952
2015-03-24 21:08:26 -07:00
Elliott Hughes
fa495d51b0 Hide statfs/fstatfs' ST_VALID flag from userspace.
Spotted while debugging the strace 4.10 upgrade.

Change-Id: I1af1be9c9440151f55f74a835e1df71529b0e4fe
2015-03-18 15:46:48 -07:00
Nick Kralevich
35778253a5 Fix "faccessat ignores flags"
The kernel system call faccessat() does not have any flags arguments,
so passing flags to the kernel is currently ignored.

Fix the kernel system call so that no flags argument is passed in.

Ensure that we don't support AT_SYMLINK_NOFOLLOW. This non-POSIX
(http://pubs.opengroup.org/onlinepubs/9699919799/functions/access.html)
flag is a glibc extension, and has non-intuitive, error prone behavior.

For example, consider the following code:

  symlink("foo.is.dangling", "foo");
  if (faccessat(AT_FDCWD, "foo", R_OK, AT_SYMLINK_NOFOLLOW) == 0) {
    int fd = openat(AT_FDCWD, "foo", O_RDONLY | O_NOFOLLOW);
  }

The faccessat() call in glibc will return true, but an attempt to
open the dangling symlink will end up failing. GLIBC documents this
as returning the access mode of the symlink itself, which will
always return true for any symlink on Linux.

Some further discussions of this are at:

  * http://lists.landley.net/pipermail/toybox-landley.net/2014-September/003617.html
  * http://permalink.gmane.org/gmane.linux.lib.musl.general/6952

AT_SYMLINK_NOFOLLOW seems broken by design. I suspect this is why this
function was never added to POSIX. (note that "access" is pretty much
broken by design too, since it introduces a race condition between
check and action). We shouldn't support this until it's clearly
documented by POSIX or we can have it produce intuitive results.

Don't support AT_EACCESS for now. Implementing it is complicated, and
pretty much useless on Android, since we don't have setuid binaries.
See http://git.musl-libc.org/cgit/musl/commit/?id=0a05eace163cee9b08571d2ff9d90f5e82d9c228
for how an implementation might look.

Bug: 18867827
Change-Id: I25b86c5020f3152ffa3ac3047f6c4152908d0e04
2015-02-24 13:40:43 -08:00
Nick Kralevich
00490ae3f3 Ensure raw fchmod/fchmodat syscalls are hidden.
In https://android-review.googlesource.com/#/c/127908/5/libc/SYSCALLS.TXT@116
Elliott said:

  for LP64 these will be hidden. for LP32 we were cowards and left
  them all public for compatibility (though i don't think we ever
  dremeled to see whether it was needed). we don't have an easy
  way to recognize additions, though, so we can't prevent adding
  new turds.

Add a mechanism to prevent the adding of new turds, and use that
mechanism on the fchmod/fchmodat system calls.

Bug: 19233951
Change-Id: I98f98345970b631a379f348df57858f9fc3d57c0
2015-02-03 12:10:30 -08:00
Nick Kralevich
3cbc6c627f Add fchmodat(AT_SYMLINK_NOFOLLOW) and fchmod O_PATH support
Many libc functions have an option to not follow symbolic
links. This is useful to avoid security sensitive code
from inadvertantly following attacker supplied symlinks
and taking inappropriate action on files it shouldn't.
For example, open() has O_NOFOLLOW, chown() has
lchown(), stat() has lstat(), etc.

There is no such equivalent function for chmod(), such as lchmod().
To address this, POSIX introduced fchmodat(AT_SYMLINK_NOFOLLOW),
which is intended to provide a way to perform a chmod operation
which doesn't follow symlinks.

Currently, the Linux kernel doesn't implement AT_SYMLINK_NOFOLLOW.
In GLIBC, attempting to use the AT_SYMLINK_NOFOLLOW flag causes
fchmodat to return ENOTSUP. Details are in "man fchmodat".

Bionic currently differs from GLIBC in that AT_SYMLINK_NOFOLLOW
is silently ignored and treated as if the flag wasn't present.

This patch provides a userspace implementation of
AT_SYMLINK_NOFOLLOW for bionic. Using open(O_PATH | O_NOFOLLOW),
we can provide a way to atomically change the permissions on
files without worrying about race conditions.

As part of this change, we add support for fchmod on O_PATH
file descriptors, because it's relatively straight forward
and could be useful in the future.

The basic idea behind this implementation comes from
https://sourceware.org/bugzilla/show_bug.cgi?id=14578 , specifically
comment #10.

Change-Id: I1eba0cdb2c509d9193ceecf28f13118188a3cfa7
2015-02-02 13:17:17 -08:00
Raghu Gandham
86d2feef9f Modify MIPS64 stat structure to match a generic one in AOSP.
The kernel version of the stat structure is used during the syscalls. After the syscall,
the kernel stat structure is converted to match the generic one. Eventually we would like
the generic stat structure and related syscalls be added to MIPS64 kernel, removing the
thunks added to AOSP.

Change-Id: I7764e80278c1cc8254754c3531ec2dda7544a8ec
2015-01-28 16:12:17 -08:00
Yabin Cui
634816055f support _POSIX_REALTIME_SIGNALS
Bug: 18489947
Change-Id: I2e834d68bc10ca5fc7ebde047b517a3074179475
2014-12-08 21:52:43 -08:00
Elliott Hughes
b86a4c7f65 Add sethostname(2).
Not very useful, but helps building stuff like toybox out of the box.

Change-Id: I110e39030452bd093a84278e019c5752d293718d
2014-11-07 16:48:27 -08:00
Haruki Hasegawa
1816025684 Add clock_settime and clock_nanosleep.
Add the missing prototypes, fix the existing prototypes to use clockid_t
rather than int, fix clock_nanosleep's failure behavior, and add simple
tests.

Bug: 17644443
Bug: https://code.google.com/p/android/issues/detail?id=77372
Change-Id: I03fba369939403918abcabae9551a7123953d780
Signed-off-by: Haruki Hasegawa <h6a.h4i.0@gmail.com>
2014-10-13 17:04:10 -07:00
Elliott Hughes
b587f339db Add posix_fadvise(3).
(cherry-pick of 00008263782e484020420c606f7d145fe7d0a4d8.)

Bug: 12449798
Change-Id: I07cbf3f670a0d1304b68148325a774f266b5c433
2014-09-11 08:45:46 -07:00
Elliott Hughes
011e111d29 Ensure __set_errno is still visible on LP32.
The use of the .hidden directive to avoid going via the PLT for
__set_errno had the side-effect of actually making __set_errno
hidden (which is odd because assembler directives don't usually
affect symbols defined in a different file --- you can't even
create a weak reference to a symbol that's defined in a different
file).

This change switches the system call stubs over to a new always-hidden
__set_errno_internal and has a visible __set_errno on LP32 just for
binary compatibility with old NDK apps.

(cherry-pick of 7efad83d430f4d824f2aaa75edea5106f6ff8aae.)

Bug: 17423135
Change-Id: I6b6d7a05dda85f923d22e5ffd169a91e23499b7b
2014-09-08 16:46:50 -07:00
Dan Albert
47793d6a29 Remove _flush_cache(2) for mips64.
Also remove declaration.

The only user is compiler-rt, and they can replace that call with one to
syscall(2). compiler-rt doesn't currently build on mips64 anyway.

Bug: 11156955
Change-Id: Ieae0ba49c8e7aa50253401fc1d7c2d17bc867d39
2014-08-21 13:32:37 -07:00
Dan Albert
bc9f9f25bf Make __set_errno hidden in asm.
This fixes the build after the -Bsymbolic change.

Bug: 16853291
Change-Id: I989c9fec3c32e0289ea257a3bd2b7fd2709b6ce2
2014-08-08 15:35:47 -07:00
Elliott Hughes
79310994d2 Implement <sys/fsuid.h>.
Change-Id: I1e5e50444a1b5a430ba5b5d9b8b1d91219af5e92
2014-07-30 15:19:29 -07:00
Elliott Hughes
3f525d41c2 Add splice, tee, and vmsplice.
Change-Id: I5f43380b88d776a8bb607b47dbbc5db5a2fe6163
2014-06-24 19:03:31 -07:00
Elliott Hughes
7086ad6919 Cache getpid.
In practice, with this implementation we never need to make a system call.
We get the main thread's tid (which is the same as our pid) back from
the set_tid_address system call we have to make during initialization.
A new pthread will have the same pid as its parent, and a fork child's
main (and only) thread will have a pid equal to its tid, which we get for
free from the kernel before clone returns.

The only time we'd actually have to make a getpid system call now is if
we take a signal during fork and the signal handler calls getpid. (That,
or we call getpid in the dynamic linker while it's still dealing with its
own relocations and hasn't even set up the main thread yet.)

Bug: 15387103
Change-Id: I6d4718ed0a5c912fc75b5f738c49a023dbed5189
2014-06-20 09:06:57 -07:00
Dan Albert
607341e226 Remove ioprio_get(2) and ioprio_set(2) from LP64.
Bug: 11156955
Change-Id: I07b596d85e4bd6347d488d1a92c8d0a00b5ef3b3
2014-06-12 18:10:13 -07:00
Elliott Hughes
3d5cb30d23 Remove getdents from bionic.
Bug: 11156955
Change-Id: I6c306989801be552d85fba8a50dcdc79282fb9d2
2014-06-06 15:05:58 -07:00
Elliott Hughes
5d9a7ba0dc Avoid a system call in 'gettid'.
System calls can be pretty slow. This is mako, which has one of our
lowest latencies:

                       iterations      ns/op
  BM_unistd_getpid       10000000        209
  BM_unistd_gettid      200000000          8

Bug: 15297299 (kernel panic from too many gettid calls)
Bug: 15315766 (excessive gettid overhead in liblogd)
Change-Id: I49656c0fc5b5d092390264a59e4f2c0d8a8b1aeb
2014-06-02 10:32:55 -07:00
Elliott Hughes
b30aff405a Revert "Revert "Lose the hand-written futex assembler.""
The problem with the original patch was that using syscall(3) means that
errno can be set, but pthread_create(3) was abusing the TLS errno slot as
a pthread_mutex_t for the thread startup handshake.

There was also a mistake in the check for syscall failures --- it should
have checked against -1 instead of 0 (not just because that's the default
idiom, but also here because futex(2) can legitimately return values > 0).

This patch stops abusing the TLS errno slot and adds a pthread_mutex_t to
pthread_internal_t instead. (Note that for LP64 sizeof(pthread_mutex_t) >
sizeof(uintptr_t), so we could potentially clobber other TLS slots too.)

I've also rewritten the LP32 compatibility stubs to directly reuse the
code from the .h file.

This reverts commit 75c55ff84e.

Bug: 15195455
Change-Id: I6ffb13e5cf6a35d8f59f692d94192aae9ab4593d
2014-05-28 18:31:15 -07:00
Narayan Kamath
75c55ff84e Revert "Lose the hand-written futex assembler."
This reverts commit ced906c849.

Causes issues on art / dalvik due to a broken return value
check and other undiagnosed issues.

bug: 15195455

Change-Id: I5d6bbb389ecefb0e33a5237421a9d56d32a9317c
2014-05-28 18:03:01 +00:00
Elliott Hughes
ced906c849 Lose the hand-written futex assembler.
Also stop exporting 'futex'.

Bug: 12250341
Change-Id: Icc4fa4296cd04dfe0d1061822c69e2eb40c3433a
2014-05-22 19:49:11 -07:00
Elliott Hughes
6e599a904b Remove the tkill(2) stub.
glibc doesn't have tkill or tgkill and says "use syscall(3) instead".
I've left tgkill since it's quite widely used, but there's no reason
to have tkill as well.

Bug: 11156955
Change-Id: Ifc0af750320086f829bc9914551c172b501f3b60
2014-05-22 13:41:36 -07:00
Elliott Hughes
46a55a4478 Remove __syslog; we have the public klogctl API.
Bug: 11156955
Change-Id: I5c2cc02f39f76dd32984135f5c12c10bf2853796
2014-05-20 21:01:00 -07:00
Elliott Hughes
4e631ba568 Remove perf_event_open.
This was accidentally added at a time when you couldn't add a constant
to <syscall.h> without generating an assembly stub! (You no longer need
to add the constants at all.)

Bug: 11156955
Change-Id: I053c17879138787976c744a5ecf7d30ee51dc48f
2014-05-20 16:24:55 -07:00
Sreeram Ramachandran
903b78873a Mark sockets on creation (socket()) and accept4().
Remove the separate syscall for accept() and implement it as accept4(..., 0).

Change-Id: Ib0b8f5d7c5013b91eae6bbc3847852eb355c7714
2014-05-19 15:19:16 -07:00
Elliott Hughes
7222b1b594 Hide __signalfd4, used to implement signalfd(3).
Bug: 11156955
Change-Id: I50842279cb5b32ec8bd45193435574e415cd806e
2014-05-16 15:47:29 -07:00
Sreeram Ramachandran
8f0cd8aa22 Mark sockets on accept().
(cherry picked from commit 58b1f3f6a30a660ad81637c2b50382c3d279243b)

Change-Id: I5d09be413cf720fbed905f96313b007997ada76c
2014-05-14 11:10:22 -07:00
Sreeram Ramachandran
ceb5bd787c Introduce netd_client, a dynamic library that talks to netd.
The library exists outside bionic. It is dynamically loaded, to replace selected
standard socket syscalls with versions that talk to netd.

Change connect() to use the library if available.

(cherry picked from commit 3a6b627a14df8111b03e452f2df4b5f4938e0e49)

Change-Id: Ib6198e19dbc306521a26fcecfdf6e8424d163fc9
2014-05-13 11:30:03 -07:00
Elliott Hughes
dcbef06ce6 Remove the useless indirection in mips' __set_tls.
Change-Id: I12e9d6716c42ccbccc9a186441aca0736bb22d05
2014-05-12 16:11:06 -07:00
Elliott Hughes
9f525644df Implement _Exit(3).
Change-Id: Ida6ac844cc87d38c9645b197dd8188bb73e27dbe
2014-04-08 17:16:13 -07:00
Andrei Emeltchenko
8f2a30a92a Add accept4() syscall
Add accept4() using SYSCALLS.TXT and gensyscall

Change-Id: I6f19f29144186d15d46423e10f2cc4b4223719c6
2014-03-26 15:50:01 +02:00
Guillaume Ranquet
6ff0c75c83 Add recvmmsg and sendmmsg syscalls.
Also add the corresponding constant, struct, and function declarations
to <sys/socket.h>, and perfunctory tests so we know that the symbols
actually exist.

Signed-off-by: Guillaume Ranquet <guillaumex.ranquet@intel.com>
Change-Id: Ib0d854239d3716be90ad70973c579aff4895a4f7
2014-02-27 14:29:01 -08:00
Elliott Hughes
d465eb4e76 Remove the useless _C_LABEL from generated system calls.
Change-Id: Id1d2fd39972652831ea825f6f9cf940b08f42b5c
2014-02-19 18:59:19 -08:00
Elliott Hughes
9abbbdc534 Make mips/mips64 syscall stubs more like the other architectures.
Change-Id: I55f8c1a95f643a6e484f12fbcc25e2c77e55b6b8
2014-02-19 14:54:31 -08:00
Elliott Hughes
986f906710 Fix build by avoiding the _C_LABEL macro.
Change-Id: Ide367c2b65071388bd95fbc81a4ed6ae94aec4e4
2014-02-18 16:42:36 -08:00
Elliott Hughes
db1ea34748 Implement some of the missing LFS64 support.
This gives us:

* <dirent.h>
  struct dirent64
  readdir64, readdir64_r, alphasort64, scandir64

* <fcntl.h>
  creat64, openat64, open64.

* <sys/stat.h>
  struct stat64
  fstat64, fstatat64, lstat64, stat64.

* <sys/statvfs.h>
  struct statvfs64
  statvfs64, fstatvfs64.

* <sys/vfs.h>
  struct statfs64
  statfs64, fstatfs64.

This also removes some of the incorrect #define hacks we've had in the
past (for stat64, for example, which we promised to clean up way back
in bug 8472078).

Bug: 11865851
Bug: 8472078
Change-Id: Ia46443521918519f2dfa64d4621027dfd13ac566
2014-02-18 15:39:24 -08:00
Chris Dearman
5043212b76 [MIPS64] Add syscall related files
Change-Id: I2f5d05df0e767538a6fe467ca0a2386325f8b71f
Signed-off-by: Chris Dearman <chris.dearman@imgtec.com>
Signed-off-by: Raghu Gandham <raghu.gandham@imgtec.com>
Signed-off-by: Duane Sand <duane.sand@imgtec.com>
2014-02-06 15:39:38 -08:00