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Don't read more dirents from Linux than we can handle
This was causing some directory entries to be skipped because we were reading more directory entries from Linux than we had space for in the user provided buffer
+33
-4
+33
-4
src/kernel/emulation/linux/dirent/getdirentries.c
+33
-4
src/kernel/emulation/linux/dirent/getdirentries.c
···
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#include "../errno.h"
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#include <linux-syscalls/linux.h>
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#include <sys/dirent.h>
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//#include "../simple.h"
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#define LINUX_SEEK_SET 0
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#define LINUX_SEEK_CUR 1
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extern __SIZE_TYPE__ strlen(const char* s);
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extern char* strcpy(char* dest, const char* src);
···
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# define min(a,b) ((a) < (b)) ? (a) : (b)
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#endif
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#define ALIGN(x, alignment) (((x) + (alignment - 1)) & ~(alignment - 1))
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#define BSD_DIRENT_MIN_SIZE ALIGN(sizeof(struct bsd_dirent) + 2, 4)
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#define BSD_DIRENT64_MIN_SIZE ALIGN(sizeof(struct bsd_dirent64) + 2, 4)
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#define LINUX_DIRENT64_MIN_SIZE ALIGN(sizeof(struct linux_dirent64) + 2, 8)
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static inline void round_to_4(unsigned short* reclen)
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{
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if (*reclen & 3)
···
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long sys_getdirentries(int fd, char* ibuf, unsigned int len, long* basep)
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{
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int ret, bpos = 0, opos = 0;
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char buf[1024];
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unsigned int max_entry_count = len / BSD_DIRENT_MIN_SIZE;
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// don't want to blow up the stack
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if (max_entry_count > 20)
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max_entry_count = 20;
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char buf[max_entry_count * LINUX_DIRENT64_MIN_SIZE];
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if (basep)
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*basep = 0;
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ret = LINUX_SYSCALL(__NR_getdents64, fd, buf, min(len, sizeof(buf)));
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ret = LINUX_SYSCALL(__NR_getdents64, fd, buf, sizeof(buf));
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if (ret < 0)
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return errno_linux_to_bsd(ret);
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···
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long sys_getdirentries64(int fd, char* ibuf, unsigned int len, long* basep)
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{
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int ret, bpos = 0, opos = 0;
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char buf[1024];
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unsigned int max_entry_count = len / BSD_DIRENT64_MIN_SIZE;
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// don't want to blow up the stack
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if (max_entry_count > 20)
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max_entry_count = 20;
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char buf[max_entry_count * LINUX_DIRENT64_MIN_SIZE];
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if (basep)
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*basep = 0;
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ret = LINUX_SYSCALL(__NR_getdents64, fd, buf, min(len, sizeof(buf)));
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ret = LINUX_SYSCALL(__NR_getdents64, fd, buf, sizeof(buf));
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if (ret < 0)
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return errno_linux_to_bsd(ret);
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···
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opos += bsd->d_reclen;
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bpos += l64->d_reclen;
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}
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/*
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if (bpos < ret) {
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__simple_printf("bpos < ret; %d < %d", bpos, ret);
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}
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*/
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return opos;
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}