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as an NIS client. The pw_breakout_yp routines that are used to populate the _pw_passwd structire only do anything if the bits in the pw_fields member _pw_passwd are cleared. Unfortunately, we can get into a state where pw_fields has garbage in it right before the YP lookup functions are called, which causes the breakout functions to screw up in a big way. Here's how to duplicate the problem: - Configure FreeBSD as an NIS client - Log in as a user who's password database records reside only in the NIS passwd maps. - Type ps -aux Result: your processes appear to be owned by 'root' or 'deamon.' /bin/ls can exhibit the same problem. The reason this happens: - When ps(1) needs to match a username to a UID, it calls getpwuid(). - root is in the local password file, so getpwuid() calls __hashpw() and __hashpw() populates the _pw_passwd struct, including the pw_fields member. This happens before NIS lookups take place because, by coincidence, ps(1) tends to display processes owned by root before it happens upon a proccess owned by you. - When your UID comes up, __hashpw() fails to find your entry in the local password database, so it bails out, BUT THE BITS IN THE pw_fields STRUCTURE OF _pw_passwd ARE NEVER CLEARED AND STILL CONTAIN INFORMATION FROM THE PREVIOUS CALL TO __hash_pw()!! - If we have NIS enabled, the NIS lookup functions are called. - The pw_breakout_yp routines see that the pw_fields bits are set and decline to place the data retrieved from the NIS passwd maps into the _pw_passwd structure. - getpwuid() returns the results of the last __hashpw() lookup instead of the valid NIS data. - Hijinxs ensue when user_from_uid() caches this bogus information and starts handing out the wrong usernames. AAAARRRRRRRRRGGGGGGHHHHHHHHHH!!! *Please* don't tell me I'm the only person to have noticed this. Fixed by having __hashpw() check the state of pw_fields just before bailing out on a failed lookup and clearing away any leftover garbage. What a fun way to spend an afternoon. |
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.. | ||
csu/i386 | ||
libc | ||
libcom_err | ||
libcompat | ||
libcrypt | ||
libcurses | ||
libedit | ||
libf2c | ||
libF77 | ||
libforms | ||
libI77 | ||
libkvm | ||
libm | ||
libmd | ||
libmytinfo | ||
libncurses | ||
libpam/modules | ||
libpcap | ||
libresolv | ||
librpc | ||
librpcsvc | ||
libscsi | ||
libskey | ||
libss | ||
libtelnet | ||
libterm | ||
libtermcap | ||
libutil | ||
liby | ||
msun | ||
ncurses/ncurses | ||
rpcsvc | ||
Makefile | ||
Makefile.inc |