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On Sat, Feb 17, 2007 at 09:39:58AM -0500, Mike Frysinger wrote: |
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> On Saturday 17 February 2007, Brian Harring wrote: |
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> > Security impact is from a pkg potentially dragging along old libs; if |
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> > you've got a stable pkg that gets an update once every blue moon, it |
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> > can hold onto the lib for a *long* time while still using the lib; |
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> > thus if a vuln. in the lib, said pkg still is screwed. |
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> |
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> umm, no ... the package itself is updated against the new copy while the old |
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> copy exists for other packages that have already been built |
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Suspect you're ignoring soname changes, which is about all this patch |
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would address- for example, ssl's old form of breakage. In that case, |
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*yes* the package gets updated, anything recompiled should get the |
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correct lib (assuming the code knows the appropriate linker args), but |
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the old vuln. lib still will hang around as long as anything refs it. |
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> > Other angle is someone intentionally forcing usage of a known bad |
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> > library that is still dangling. Corner case, but doable. |
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> |
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> as i said, this is the "invalid" syntax: |
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> ... /usr/lib/libfoo.so.3 ... |
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Not to LD_PRELOAD :) |
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Haven't tried anything crazy, but suspect it can be abused to override |
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to the old. |
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> > Bit curious how this is going to behave if via linked in libs, new loc |
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> > and old get loaded alongside... |
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> |
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> this would require multiple libraries to be involved in the equation and the |
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> answer is undefined behavior which most certainly result in runtime |
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> failures ... |
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Point there was that instead of just bailing with "lib is missing", |
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suspect it'll manage to run, then segfault at potentially crappy |
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times. |
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~harring |
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