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Added some tests around seek integer overflow/underflow

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Original tests provided by m-kostrzewa, these identify signed overflow
(undefined behavior) when compiled with -fsanitize=undefined.
This commit is contained in:
Christopher Haster
2024-09-24 13:31:23 -05:00
parent b78afe2518
commit f1c430e779
1 changed files with 108 additions and 0 deletions
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tests/test_seek.toml
+108
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@@ -405,3 +405,111 @@ code = '''
lfs_file_close(&lfs, &file) => 0; lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0; lfs_unmount(&lfs) => 0;
''' '''
# test possible overflow/underflow conditions
#
# note these need -fsanitize=undefined to consistently detect
# overflow/underflow conditions
[cases.test_seek_filemax]
code = '''
lfs_t lfs;
lfs_format(&lfs, cfg) => 0;
lfs_mount(&lfs, cfg) => 0;
lfs_file_t file;
lfs_file_open(&lfs, &file, "kitty",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
uint8_t buffer[1024];
strcpy((char*)buffer, "kittycatcat");
size_t size = strlen((char*)buffer);
lfs_file_write(&lfs, &file, buffer, size) => size;
// seek with LFS_SEEK_SET
lfs_file_seek(&lfs, &file, LFS_FILE_MAX, LFS_SEEK_SET) => LFS_FILE_MAX;
// seek with LFS_SEEK_CUR
lfs_file_seek(&lfs, &file, 0, LFS_SEEK_CUR) => LFS_FILE_MAX;
// the file hasn't changed size, so seek end takes us back to the offset=0
lfs_file_seek(&lfs, &file, +10, LFS_SEEK_END) => size+10;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''
[cases.test_seek_underflow]
code = '''
lfs_t lfs;
lfs_format(&lfs, cfg) => 0;
lfs_mount(&lfs, cfg) => 0;
lfs_file_t file;
lfs_file_open(&lfs, &file, "kitty",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
uint8_t buffer[1024];
strcpy((char*)buffer, "kittycatcat");
size_t size = strlen((char*)buffer);
lfs_file_write(&lfs, &file, buffer, size) => size;
// underflow with LFS_SEEK_CUR, should error
lfs_file_seek(&lfs, &file, -(size+10), LFS_SEEK_CUR) => LFS_ERR_INVAL;
lfs_file_seek(&lfs, &file, -LFS_FILE_MAX, LFS_SEEK_CUR) => LFS_ERR_INVAL;
lfs_file_seek(&lfs, &file, -(size+LFS_FILE_MAX), LFS_SEEK_CUR)
=> LFS_ERR_INVAL;
// underflow with LFS_SEEK_END, should error
lfs_file_seek(&lfs, &file, -(size+10), LFS_SEEK_END) => LFS_ERR_INVAL;
lfs_file_seek(&lfs, &file, -LFS_FILE_MAX, LFS_SEEK_END) => LFS_ERR_INVAL;
lfs_file_seek(&lfs, &file, -(size+LFS_FILE_MAX), LFS_SEEK_END)
=> LFS_ERR_INVAL;
// file pointer should not have changed
lfs_file_tell(&lfs, &file) => size;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''
[cases.test_seek_overflow]
code = '''
lfs_t lfs;
lfs_format(&lfs, cfg) => 0;
lfs_mount(&lfs, cfg) => 0;
lfs_file_t file;
lfs_file_open(&lfs, &file, "kitty",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
uint8_t buffer[1024];
strcpy((char*)buffer, "kittycatcat");
size_t size = strlen((char*)buffer);
lfs_file_write(&lfs, &file, buffer, size) => size;
// seek to LFS_FILE_MAX
lfs_file_seek(&lfs, &file, LFS_FILE_MAX, LFS_SEEK_SET) => LFS_FILE_MAX;
// overflow with LFS_SEEK_CUR, should error
lfs_file_seek(&lfs, &file, +10, LFS_SEEK_CUR) => LFS_ERR_INVAL;
lfs_file_seek(&lfs, &file, +LFS_FILE_MAX, LFS_SEEK_CUR) => LFS_ERR_INVAL;
// LFS_SEEK_SET/END don't care about the current file position, but we can
// still overflow with a large offset
// overflow with LFS_SEEK_SET, should error
lfs_file_seek(&lfs, &file,
+((uint32_t)LFS_FILE_MAX+10),
LFS_SEEK_SET) => LFS_ERR_INVAL;
lfs_file_seek(&lfs, &file,
+((uint32_t)LFS_FILE_MAX+(uint32_t)LFS_FILE_MAX),
LFS_SEEK_SET) => LFS_ERR_INVAL;
// overflow with LFS_SEEK_END, should error
lfs_file_seek(&lfs, &file, +(LFS_FILE_MAX-size+10), LFS_SEEK_END)
=> LFS_ERR_INVAL;
lfs_file_seek(&lfs, &file, +(LFS_FILE_MAX-size+LFS_FILE_MAX), LFS_SEEK_END)
=> LFS_ERR_INVAL;
// file pointer should not have changed
lfs_file_tell(&lfs, &file) => LFS_FILE_MAX;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''