{bp-19444} libs/libc: Fix divide-by-zero in stat() with large filesystem block sizes - #19622
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Move uid_t/gid_t out of the CONFIG_SMALL_MEMORY #ifdef so they are always defined as unsigned int regardless of SMALL_MEMORY. Update include/nuttx/fs/hostfs.h to match: drop the int16_t variants of nuttx_gid_t/nuttx_uid_t and keep a single unsigned int definition so the hostfs RPC ABI stays in sync with sys/types.h. Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
A 16-bit ino_t can only address 65536 distinct file serial numbers, which is not enough for filesystems with large directory trees and breaks portable software (e.g. dropbear's scp) that expects a wider inode number space. Widen ino_t (and nuttx_ino_t in the hostfs ABI) to uint32_t to match common POSIX practice. Update fs/rpmsgfs/rpmsgfs.h accordingly: promote the 'ino' field in struct rpmsgfs_stat_priv_s from uint16_t to uint32_t and move 'nlink' into the trailing 16-bit slot previously occupied by the reserved field, keeping the overall packed-struct layout/size unchanged. Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Add the POSIX d_ino (file serial number) member to struct dirent and
populate it on every readdir() path, so portable callers (e.g. scp in
dropbear) that read dp->d_ino observe a meaningful, non-zero inode
number:
- include/dirent.h: declare d_ino in struct dirent and drop the
outdated comment claiming the field is unimplemented.
- include/nuttx/fs/hostfs.h: add d_ino to struct nuttx_dirent_s so
the hostfs ABI can carry the inode number across the VFS boundary.
- arch/sim/src/sim/posix/sim_hostfs.c: forward the host's
ent->d_ino into entry->d_ino.
- fs/vfs/fs_dir.c (read_pseudodir): copy the in-memory inode's
i_ino into entry->d_ino for the pseudo filesystem.
- fs/yaffs/yaffs_vfs.c: forward yaffs's dirent->d_ino into
entry->d_ino.
- fs/rpmsgfs: extend struct rpmsgfs_readdir_s with an 'ino' field
and propagate it across the RPC in both rpmsgfs_server (fills it
from the underlying entry) and rpmsgfs_client (writes it back to
the caller's nuttx_dirent_s).
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
…izes blksize_t is currently defined as int16_t, which overflows when a filesystem reports a block size larger than 32767 bytes. This causes st_blksize to become zero, leading to an integer divide-by-zero when st_blocks is calculated in stat(). Widen blksize_t to int32_t to support larger filesystem block sizes. Update nuttx_blksize_t in include/nuttx/fs/hostfs.h to keep it consistent with include/sys/types.h. struct geometry.geo_sectorsize (include/nuttx/fs/ioctl.h) is also typed blksize_t, so every debug print of that field using a 16-bit format specifier is updated to PRId32 to match the new width: drivers/misc/ramdisk.c, drivers/mmcsd/mmcsd_spi.c, drivers/mtd/ftl.c, fs/driver/fs_blockmerge.c, drivers/mtd/smart.c, drivers/usbhost/usbhost_storage.c, drivers/mmcsd/mmcsd_sdio.c, arch/arm/src/s32k1xx/s32k1xx_eeeprom.c, arch/arm/src/lc823450/lc823450_mmcl.c. Signed-off-by: Ansh Rai <anshrai331@gmail.com> Signed-off-by: root <root@LAPTOP-9C7LKDC5.localdomain>
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xiaoxiang781216
August 3, 2026 08:28
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Summary
This change fixes a divide-by-zero in stat() caused by overflow of st_blksize when a filesystem reports a block size larger than can be represented by blksize_t. As reported in #19432, this can occur with LittleFS configurations using large block sizes, where blksize_t is currently defined as int16_t. When the filesystem block size exceeds the range of int16_t, st_blksize is truncated to zero, causing an integer divide-by-zero when st_blocks is calculated.
This patch widens blksize_t from int16_t to int32_t in include/sys/types.h and updates the corresponding nuttx_blksize_t definition in include/nuttx/fs/hostfs.h so the two definitions remain consistent.
Fixes #19432
Includes:
#19179
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