libmultipath: check get_word() result in disassemble_map() - #155
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wallycheng wants to merge 1 commit into
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libmultipath: check get_word() result in disassemble_map()#155wallycheng wants to merge 1 commit into
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get_word() leaves *word == NULL and returns 0 if its internal calloc() fails, which can happen under memory pressure. Every other call site in disassemble_map() checks for this case, but the path-arguments loop skipped the check before calling atoi(word), causing a NULL-pointer dereference on the OOM path. Jump to the existing out1 label, which already frees word, to match the rest of the function and bail out cleanly. Signed-off-by: wallycheng <295412260@qq.com>
wallycheng
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August 14, 2026 04:12
wallycheng
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August 14, 2026 04:13
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@mwilck Hi, Could you take a look please? Thanks! |
bmarzins
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Aug 14, 2026
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Thanks for the patch! It looks good other than two nitpicks.
- Would you mind changing the commit message? This is not just a problem on OOM (which is unlikely to happen in practice). A malformed multipath table, where the last path has no arguments, will also cause a crash, and that seems like a more likely thing to happen.
- since we know word is NULL, we might as well just jump to
out, instead ofout1.
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get_word() leaves *word == NULL and returns 0 if its internal
calloc() fails, which can happen under memory pressure. Every
other call site in disassemble_map() checks for this case, but the
path-arguments loop skipped the check before calling atoi(word),
causing a NULL-pointer dereference on the OOM path.
Jump to the existing out1 label, which already frees word, to
match the rest of the function and bail out cleanly.