1. 12 4月, 2018 14 次提交
  2. 28 3月, 2018 1 次提交
  3. 16 3月, 2018 1 次提交
  4. 13 2月, 2018 2 次提交
  5. 12 2月, 2018 1 次提交
    • L
      vfs: do bulk POLL* -> EPOLL* replacement · a9a08845
      Linus Torvalds 提交于
      This is the mindless scripted replacement of kernel use of POLL*
      variables as described by Al, done by this script:
      
          for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
              L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
              for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
          done
      
      with de-mangling cleanups yet to come.
      
      NOTE! On almost all architectures, the EPOLL* constants have the same
      values as the POLL* constants do.  But they keyword here is "almost".
      For various bad reasons they aren't the same, and epoll() doesn't
      actually work quite correctly in some cases due to this on Sparc et al.
      
      The next patch from Al will sort out the final differences, and we
      should be all done.
      Scripted-by: NAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a9a08845
  6. 07 2月, 2018 13 次提交
  7. 01 2月, 2018 2 次提交
  8. 20 1月, 2018 1 次提交
    • A
      proc: fix coredump vs read /proc/*/stat race · 8bb2ee19
      Alexey Dobriyan 提交于
      do_task_stat() accesses IP and SP of a task without bumping reference
      count of a stack (which became an entity with independent lifetime at
      some point).
      
      Steps to reproduce:
      
          #include <stdio.h>
          #include <sys/types.h>
          #include <sys/stat.h>
          #include <fcntl.h>
          #include <sys/time.h>
          #include <sys/resource.h>
          #include <unistd.h>
          #include <sys/wait.h>
      
          int main(void)
          {
          	setrlimit(RLIMIT_CORE, &(struct rlimit){});
      
          	while (1) {
          		char buf[64];
          		char buf2[4096];
          		pid_t pid;
          		int fd;
      
          		pid = fork();
          		if (pid == 0) {
          			*(volatile int *)0 = 0;
          		}
      
          		snprintf(buf, sizeof(buf), "/proc/%u/stat", pid);
          		fd = open(buf, O_RDONLY);
          		read(fd, buf2, sizeof(buf2));
          		close(fd);
      
          		waitpid(pid, NULL, 0);
          	}
          	return 0;
          }
      
          BUG: unable to handle kernel paging request at 0000000000003fd8
          IP: do_task_stat+0x8b4/0xaf0
          PGD 800000003d73e067 P4D 800000003d73e067 PUD 3d558067 PMD 0
          Oops: 0000 [#1] PREEMPT SMP PTI
          CPU: 0 PID: 1417 Comm: a.out Not tainted 4.15.0-rc8-dirty #2
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1.fc27 04/01/2014
          RIP: 0010:do_task_stat+0x8b4/0xaf0
          Call Trace:
           proc_single_show+0x43/0x70
           seq_read+0xe6/0x3b0
           __vfs_read+0x1e/0x120
           vfs_read+0x84/0x110
           SyS_read+0x3d/0xa0
           entry_SYSCALL_64_fastpath+0x13/0x6c
          RIP: 0033:0x7f4d7928cba0
          RSP: 002b:00007ffddb245158 EFLAGS: 00000246
          Code: 03 b7 a0 01 00 00 4c 8b 4c 24 70 4c 8b 44 24 78 4c 89 74 24 18 e9 91 f9 ff ff f6 45 4d 02 0f 84 fd f7 ff ff 48 8b 45 40 48 89 ef <48> 8b 80 d8 3f 00 00 48 89 44 24 20 e8 9b 97 eb ff 48 89 44 24
          RIP: do_task_stat+0x8b4/0xaf0 RSP: ffffc90000607cc8
          CR2: 0000000000003fd8
      
      John Ogness said: for my tests I added an else case to verify that the
      race is hit and correctly mitigated.
      
      Link: http://lkml.kernel.org/r/20180116175054.GA11513@avx2Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
      Reported-by: N"Kohli, Gaurav" <gkohli@codeaurora.org>
      Tested-by: NJohn Ogness <john.ogness@linutronix.de>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8bb2ee19
  9. 07 12月, 2017 1 次提交
  10. 28 11月, 2017 4 次提交
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