Don't crash when using readdir_r() if name_max is determined to be 0 #1903
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If using HAVE_STATVFS, set name_max from svfs.f_namelen instead of sfs.f_namelen, to be consistent with the rest of the function. Noticed by code inspection.
Add error handling to the USE_READDIR_R code paths that set name_max from struct statfs or statvfs; if the determined name_max == 0 then return an error. Avoids a crash in tree_dir_next_posix() when the calculation of dirent_size from name_max is too small for the memory allocated for struct dirent. This may fix Github issue #1149 This may fix NetBSD PR https://gnats.netbsd.org/56080
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Arguably the error paths I added could instead attempt to fall back to NAME_MAX (if defined) or PATH_MAX, similar to the "generic" setup_current_filesystem() variant which has the code: I wasn't sure what the preferred technique was from the libarchive maintainers, so I chose to just fail hard instead. |
netbsd-srcmastr
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Add error handling to the USE_READDIR_R code paths that set name_max from struct statfs or statvfs; if the determined name_max == 0 then return an error. Avoids a crash in tree_dir_next_posix() when the calculation of dirent_size from name_max is too small for the memory allocated for struct dirent. Submitted to upstream in pull request libarchive/libarchive#1903 Should fix PR bin/56080
mmatuska
approved these changes
Jul 13, 2023
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Avoid a crash when the memory allocated for the
struct direntwritten to byreaddir_r()isn't large enough because filesystem.name_max==0 (as copied fromstruct statfsorstruct statvfs), so there's a memory overwrite.This should fix issue #1149 and NetBSD PR https://gnats.netbsd.org/56080.